20 Tailwind CSS Mega Menus
03 / 20

All 20 in 20 Tailwind CSS Mega Menus

  1. 01Tailwind CSS Mega Menu with Focus-Within (No JavaScript)
  2. 02Tailwind Mega Menu with Hover Intent Delay (No Flicker)
  3. 03Tailwind Mega Menu Safe Triangle (Diagonal Hover Fix)
  4. 04Tailwind CSS Grid Mega Menu with Subgrid Column Layout
  5. 05Tailwind Mega Menu Viewport Edge Positioning with Anchor Positioning
  6. 06Full-Width Tailwind Mega Menu Inside a Contained Header
  7. 07Accessible Tailwind Mega Menu with Escape Key and Focus Return
  8. 08Tailwind Mega Menu with Arrow Key Navigation Across Columns
  9. 09Accessible ARIA Disclosure Mega Menu in Tailwind CSS
  10. 10Mobile Tailwind Mega Menu for Touch Devices (Tap to Open)
  11. 11Screen Reader Friendly Tailwind Mega Menu with Panel Summaries
  12. 12Tailwind Mega Menu with One Shared Panel That Swaps Content
  13. 13Animated Tailwind Mega Menu with @starting-style and display Transitions
  14. 14Responsive Tailwind Mega Menu: How It Should Collapse on Mobile
  15. 15Editorial Tailwind Mega Menu with Featured Article Image
  16. 16Tailwind Dashboard Mega Menu with Live Status Panel
  17. 17Tailwind Mega Menu with Category Image Cards
  18. 18Tailwind E-commerce Department Store Mega Menu Grid
  19. 19Tailwind Product Finder Mega Menu with Live Filters
  20. 20Tailwind Promotional Mega Menu with Offer Banner
Tailwind + JSMIT licensed

Tailwind Mega Menu Safe Triangle (Diagonal Hover Fix)

The diagonal-pointer problem, solved the way big retailers do it: while the pointer is travelling inside the triangle between its last position and the open panel's top corners, neighbouring triggers are ignored. A fleet-operations console draws the live triangle in a dashed SVG overlay so you can watch it work. State is a data-open attribute; every visual is a tmm03-open: utility, including the left-to-right row wipe.

Live Demo
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The code

<section class="tmm-03 relative w-full min-h-svh bg-tmm03-bg bg-[radial-gradient(60rem_28rem_at_82%_-10%,color-mix(in_oklab,var(--color-tmm03-acc)_16%,transparent),transparent_62%)] font-tmm03-sans leading-normal text-tmm03-ink [&_:focus-visible]:rounded-[4px] [&_:focus-visible]:outline-2 [&_:focus-visible]:outline-offset-3 [&_:focus-visible]:outline-tmm03-acc" aria-labelledby="tmm03-title">
  <h2 class="sr-only" id="tmm03-title">Vale Logistics operations console</h2>

  <div class="absolute top-3 right-[clamp(0.75rem,3vw,1.5rem)] z-60">
    <input class="peer absolute inset-0 m-0 size-full cursor-pointer opacity-0" type="checkbox" id="tmm03-theme">
    <label class="grid size-11 cursor-pointer place-items-center rounded-[4px] border border-tmm03-line bg-tmm03-surf text-tmm03-ink peer-focus-visible:outline-2 peer-focus-visible:outline-offset-3 peer-focus-visible:outline-tmm03-acc" for="tmm03-theme">
      <svg class="size-5" viewBox="0 0 24 24" aria-hidden="true" focusable="false"><circle cx="12" cy="12" r="8.5" fill="none" stroke="currentColor" stroke-width="1.6"/><path d="M12 3.5a8.5 8.5 0 0 0 0 17Z" fill="currentColor"/></svg>
      <span class="sr-only">Toggle dark theme</span>
    </label>
  </div>

  <header data-tmm03-header data-mode="safe" data-guard="320" class="relative z-10 w-full border-b border-tmm03-line bg-tmm03-surf pb-[clamp(11rem,26vw,14rem)] max-[52rem]:pb-0">
    <svg class="pointer-events-none absolute inset-0 z-40 size-full max-[52rem]:hidden" aria-hidden="true" focusable="false"><polygon data-tmm03-tri class="fill-tmm03-acc/20 stroke-tmm03-acc stroke-[1.5] opacity-0 transition-opacity duration-100 [stroke-dasharray:5_4]" points=""></polygon></svg>

    <div class="mx-auto flex min-h-15 w-[min(84rem,calc(100%-2rem))] flex-wrap items-center gap-x-[clamp(0.5rem,2vw,2rem)] pr-15 max-[52rem]:flex-col max-[52rem]:items-stretch max-[52rem]:py-2.5">
      <a class="inline-flex items-center gap-2 font-tmm03-mono text-[0.95rem]/none font-bold tracking-[0.06em] text-tmm03-ink uppercase" href="#tmm03-title">
        <svg class="size-[22px] text-tmm03-acc" viewBox="0 0 24 24" aria-hidden="true" focusable="false"><path d="M2 16V8h11v8Zm11-5h4l3 3.2V16h-7Z" fill="none" stroke="currentColor" stroke-width="1.7" stroke-linejoin="round"/><circle cx="7" cy="18" r="1.8" fill="currentColor"/><circle cx="17" cy="18" r="1.8" fill="currentColor"/></svg>
        Vale <span class="font-normal text-tmm03-mut">Logistics</span>
      </a>

      <nav data-tmm03-nav class="min-w-0" aria-label="Primary">
        <ul class="flex flex-wrap gap-1 max-[52rem]:flex-col">
          <li data-tmm03-item class="relative">
            <button data-tmm03-trigger type="button" aria-expanded="false" aria-controls="tmm03-panel-fleet" class="inline-flex min-h-11 cursor-pointer items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink transition-colors hover:text-tmm03-acc tmm03-open:bg-tmm03-acc tmm03-open:text-tmm03-on-acc!">Fleet</button>
            <div data-tmm03-panel class="invisible absolute top-full left-0 z-30 mt-2 w-[min(34rem,calc(100vw-3rem))] -translate-y-1.5 rounded-[4px] bg-tmm03-panel p-[clamp(0.85rem,2.4vw,1.15rem)] text-tmm03-onpanel opacity-0 shadow-tmm03-panel pointer-events-none transition-[opacity,translate,visibility] duration-150 before:absolute before:-top-1.5 before:left-6 before:size-3 before:rotate-45 before:rounded-[2px] before:bg-tmm03-panel tmm03-open:visible tmm03-open:translate-y-0 tmm03-open:opacity-100 tmm03-open:pointer-events-auto motion-reduce:transition-none max-[60rem]:w-[min(21rem,calc(100vw-3rem))] max-[52rem]:static max-[52rem]:hidden max-[52rem]:w-full max-[52rem]:visible max-[52rem]:translate-y-0 max-[52rem]:opacity-100 max-[52rem]:before:hidden max-[52rem]:tmm03-open:block" id="tmm03-panel-fleet" aria-label="Fleet">
              <p class="mb-2.5 flex items-baseline justify-between gap-3 font-tmm03-mono text-[0.7rem]/none font-bold tracking-[0.14em] uppercase">Fleet operations <span class="shrink-0 whitespace-nowrap rounded-full bg-tmm03-onpanel/8 px-2 py-1 font-normal tracking-[0.06em] normal-case">14 tools &middot; 212 depots</span></p>
              <ul class="grid grid-cols-2 gap-0.5 max-[52rem]:grid-cols-1">
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-20 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Live vehicle map</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65"><span aria-hidden="true" class="relative size-1.5 rounded-full bg-tmm03-ok before:absolute before:inset-0 before:animate-ping before:rounded-full before:bg-tmm03-ok motion-reduce:before:hidden"></span>realtime</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-60 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Route planner</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">beta</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-100 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Driver hours</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">compliance</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-140 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Maintenance queue</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">32 open</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-180 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Fuel and charging</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">daily</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-220 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Depot capacity</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">weekly</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-260 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Incident reports</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">archive</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-300 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Cost per mile</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">finance</span></a></li>
              </ul>
            </div>
          </li>

          <li data-tmm03-item class="relative">
            <button data-tmm03-trigger type="button" aria-expanded="false" aria-controls="tmm03-panel-network" class="inline-flex min-h-11 cursor-pointer items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink transition-colors hover:text-tmm03-acc tmm03-open:bg-tmm03-acc tmm03-open:text-tmm03-on-acc!">Network</button>
            <div data-tmm03-panel class="invisible absolute top-full left-0 z-30 mt-2 w-[min(34rem,calc(100vw-3rem))] -translate-y-1.5 rounded-[4px] bg-tmm03-panel p-[clamp(0.85rem,2.4vw,1.15rem)] text-tmm03-onpanel opacity-0 shadow-tmm03-panel pointer-events-none transition-[opacity,translate,visibility] duration-150 before:absolute before:-top-1.5 before:left-6 before:size-3 before:rotate-45 before:rounded-[2px] before:bg-tmm03-panel tmm03-open:visible tmm03-open:translate-y-0 tmm03-open:opacity-100 tmm03-open:pointer-events-auto motion-reduce:transition-none max-[60rem]:w-[min(21rem,calc(100vw-3rem))] max-[52rem]:static max-[52rem]:hidden max-[52rem]:w-full max-[52rem]:visible max-[52rem]:translate-y-0 max-[52rem]:opacity-100 max-[52rem]:before:hidden max-[52rem]:tmm03-open:block" id="tmm03-panel-network" aria-label="Network">
              <p class="mb-2.5 flex items-baseline justify-between gap-3 font-tmm03-mono text-[0.7rem]/none font-bold tracking-[0.14em] uppercase">Network <span class="shrink-0 whitespace-nowrap rounded-full bg-tmm03-onpanel/8 px-2 py-1 font-normal tracking-[0.06em] normal-case">6 tools</span></p>
              <ul class="grid grid-cols-2 gap-0.5 max-[52rem]:grid-cols-1">
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-20 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Depot directory</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">212 sites</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-60 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Partner carriers</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">contracts</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-100 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Coverage gaps</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">planning</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-140 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Service levels</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">SLA</span></a></li>
              </ul>
            </div>
          </li>

          <li data-tmm03-item class="relative">
            <button data-tmm03-trigger type="button" aria-expanded="false" aria-controls="tmm03-panel-reports" class="inline-flex min-h-11 cursor-pointer items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink transition-colors hover:text-tmm03-acc tmm03-open:bg-tmm03-acc tmm03-open:text-tmm03-on-acc!">Reports</button>
            <div data-tmm03-panel class="invisible absolute top-full left-0 z-30 mt-2 w-[min(34rem,calc(100vw-3rem))] -translate-y-1.5 rounded-[4px] bg-tmm03-panel p-[clamp(0.85rem,2.4vw,1.15rem)] text-tmm03-onpanel opacity-0 shadow-tmm03-panel pointer-events-none transition-[opacity,translate,visibility] duration-150 before:absolute before:-top-1.5 before:left-6 before:size-3 before:rotate-45 before:rounded-[2px] before:bg-tmm03-panel tmm03-open:visible tmm03-open:translate-y-0 tmm03-open:opacity-100 tmm03-open:pointer-events-auto motion-reduce:transition-none max-[60rem]:w-[min(21rem,calc(100vw-3rem))] max-[52rem]:static max-[52rem]:hidden max-[52rem]:w-full max-[52rem]:visible max-[52rem]:translate-y-0 max-[52rem]:opacity-100 max-[52rem]:before:hidden max-[52rem]:tmm03-open:block" id="tmm03-panel-reports" aria-label="Reports">
              <p class="mb-2.5 flex items-baseline justify-between gap-3 font-tmm03-mono text-[0.7rem]/none font-bold tracking-[0.14em] uppercase">Reports <span class="shrink-0 whitespace-nowrap rounded-full bg-tmm03-onpanel/8 px-2 py-1 font-normal tracking-[0.06em] normal-case">9 tools</span></p>
              <ul class="grid grid-cols-2 gap-0.5 max-[52rem]:grid-cols-1">
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-20 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Weekly summary</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">PDF</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-60 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Utilisation</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">dashboard</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-100 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Emissions</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">export</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-140 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Custom query</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">SQL</span></a></li>
              </ul>
            </div>
          </li>

          <li><a class="inline-flex min-h-11 items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink hover:text-tmm03-acc" href="#tmm03-title">Settings</a></li>
        </ul>
      </nav>

      <div class="ml-auto flex items-center gap-3 max-[52rem]:ml-0">
        <span class="font-tmm03-mono text-[0.72rem]/none font-medium tracking-[0.06em] text-tmm03-mut">Shift B &middot; 06:00&ndash;14:00</span>
        <span class="grid size-8 place-items-center rounded-full bg-tmm03-acc/24 font-tmm03-mono text-[0.72rem]/none font-bold text-tmm03-acc" aria-hidden="true">JL</span>
      </div>
    </div>
  </header>

  <main class="mx-auto w-[min(84rem,calc(100%-2rem))] py-[clamp(1.5rem,5vw,3rem)]">
    <dl class="grid grid-cols-[repeat(auto-fit,minmax(min(100%,13rem),1fr))] overflow-hidden rounded-[4px] border-t border-l border-tmm03-line">
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">Vehicles moving</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums ">1,284</dd><span class="text-[0.76rem] text-tmm03-mut">+3.1% vs yesterday</span></div>
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">On-time rate</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums ">96.4%</dd><span class="text-[0.76rem] text-tmm03-mut">target 95%</span></div>
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">Late at depot</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums text-tmm03-acc">37</dd><span class="text-[0.76rem] text-tmm03-mut">18 flagged for review</span></div>
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">Cost per mile</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums ">&pound;1.06</dd><span class="text-[0.76rem] text-tmm03-mut">&minus;2p this week</span></div>
    </dl>
  </main>
</section>
@import "tailwindcss";

@theme {
  --color-tmm03-bg: #17140f;
  --color-tmm03-bg: oklch(0.19 0.012 75);
  --color-tmm03-surf: #211c15;
  --color-tmm03-surf: oklch(0.23 0.015 75);
  --color-tmm03-panel: #f7f2e8;
  --color-tmm03-panel: oklch(0.96 0.014 85);
  --color-tmm03-onpanel: #1c1710;
  --color-tmm03-onpanel: oklch(0.21 0.015 75);
  --color-tmm03-line: #362e22;
  --color-tmm03-line: oklch(0.31 0.022 75);
  --color-tmm03-ink: #f3ede1;
  --color-tmm03-ink: oklch(0.95 0.015 85);
  --color-tmm03-mut: #ab9d86;
  --color-tmm03-mut: oklch(0.71 0.035 80);
  --color-tmm03-acc: #f2a63b;
  --color-tmm03-acc: oklch(0.77 0.15 70);
  --color-tmm03-on-acc: #12100e;
  --color-tmm03-on-acc: oklch(0.17 0.006 70);
  --color-tmm03-ok: #3fae6a;
  --color-tmm03-ok: oklch(0.67 0.14 150);
  --font-tmm03-sans: 'IBM Plex Sans', system-ui, sans-serif;
  --font-tmm03-mono: 'IBM Plex Mono', ui-monospace, monospace;
  --shadow-tmm03-panel: 0 30px 60px -30px rgb(0 0 0 / 0.7);
}
/* The open state as ONE variant: focus-within or a scripted [data-open] (hover is driven by the script).
   Every panel, chevron and entry utility reads tmm03-open: instead of a repeated selector list. */

@custom-variant tmm03-open {
  &:where([data-tmm03-item]:is(:focus-within, [data-open]) *) {
    @slot;
  }
}
/* Root rule: the full-bleed contract, sized before the browser build compiles. */

.tmm-03 {
  width: 100%;
  min-height: 100svh;
}
/* Theme toggle: the checkbox flips the token set; the OS preference flips the default. */

.tmm-03:has(#tmm03-theme:checked) {
  --color-tmm03-bg: #f6f3ec;
  --color-tmm03-bg: oklch(0.96 0.01 85);
  --color-tmm03-surf: #ffffff;
  --color-tmm03-surf: oklch(1 0 0);
  --color-tmm03-panel: #1c1710;
  --color-tmm03-panel: oklch(0.21 0.015 75);
  --color-tmm03-onpanel: #f7f2e8;
  --color-tmm03-onpanel: oklch(0.96 0.014 85);
  --color-tmm03-line: #ddd4c2;
  --color-tmm03-line: oklch(0.87 0.025 85);
  --color-tmm03-ink: #1c1710;
  --color-tmm03-ink: oklch(0.21 0.015 75);
  --color-tmm03-mut: #6a5f50;
  --color-tmm03-mut: oklch(0.48 0.03 75);
  --color-tmm03-acc: #a1560a;
  --color-tmm03-acc: oklch(0.52 0.14 60);
  --color-tmm03-on-acc: #ffffff;
  --color-tmm03-on-acc: oklch(1 0 0);
  --color-tmm03-ok: #2f8f55;
  --color-tmm03-ok: oklch(0.58 0.13 150);
}

@media (prefers-color-scheme: light) {
  .tmm-03 {
    --color-tmm03-bg: #f6f3ec;
    --color-tmm03-bg: oklch(0.96 0.01 85);
    --color-tmm03-surf: #ffffff;
    --color-tmm03-surf: oklch(1 0 0);
    --color-tmm03-panel: #1c1710;
    --color-tmm03-panel: oklch(0.21 0.015 75);
    --color-tmm03-onpanel: #f7f2e8;
    --color-tmm03-onpanel: oklch(0.96 0.014 85);
    --color-tmm03-line: #ddd4c2;
    --color-tmm03-line: oklch(0.87 0.025 85);
    --color-tmm03-ink: #1c1710;
    --color-tmm03-ink: oklch(0.21 0.015 75);
    --color-tmm03-mut: #6a5f50;
    --color-tmm03-mut: oklch(0.48 0.03 75);
    --color-tmm03-acc: #a1560a;
    --color-tmm03-acc: oklch(0.52 0.14 60);
    --color-tmm03-on-acc: #ffffff;
    --color-tmm03-on-acc: oklch(1 0 0);
    --color-tmm03-ok: #2f8f55;
    --color-tmm03-ok: oklch(0.58 0.13 150);
  }

  .tmm-03:has(#tmm03-theme:checked) {
    --color-tmm03-bg: #17140f;
    --color-tmm03-bg: oklch(0.19 0.012 75);
    --color-tmm03-surf: #211c15;
    --color-tmm03-surf: oklch(0.23 0.015 75);
    --color-tmm03-panel: #f7f2e8;
    --color-tmm03-panel: oklch(0.96 0.014 85);
    --color-tmm03-onpanel: #1c1710;
    --color-tmm03-onpanel: oklch(0.21 0.015 75);
    --color-tmm03-line: #362e22;
    --color-tmm03-line: oklch(0.31 0.022 75);
    --color-tmm03-ink: #f3ede1;
    --color-tmm03-ink: oklch(0.95 0.015 85);
    --color-tmm03-mut: #ab9d86;
    --color-tmm03-mut: oklch(0.71 0.035 80);
    --color-tmm03-acc: #f2a63b;
    --color-tmm03-acc: oklch(0.77 0.15 70);
    --color-tmm03-on-acc: #12100e;
    --color-tmm03-on-acc: oklch(0.17 0.006 70);
    --color-tmm03-ok: #3fae6a;
    --color-tmm03-ok: oklch(0.67 0.14 150);
  }
}
(() => {
  const root = document.querySelector('.tmm-03');
  if (!root || root.__tmmCleanup) return;
  const header = root.querySelector('[data-tmm03-header]');
  const nav = root.querySelector('[data-tmm03-nav]');
  const tri = root.querySelector('[data-tmm03-tri]');
  const guardMs = Number(header.dataset.guard || 320);
  let last = null, corners = null, guardT = 0, armed = false;

  const setOpen = (item, on) => {
    item.toggleAttribute('data-open', on);
    item.querySelector('[data-tmm03-trigger]').setAttribute('aria-expanded', String(on));
  };
  const openItem = (item) => {
    nav.querySelectorAll('[data-tmm03-item][data-open]').forEach((i) => { if (i !== item) setOpen(i, false); });
    setOpen(item, true);
    const r = item.querySelector('[data-tmm03-panel]').getBoundingClientRect();
    const h = header.getBoundingClientRect();
    corners = [[r.left - h.left, r.top - h.top], [r.right - h.left, r.top - h.top]];
  };
  const sign = (a, b, c) => (a[0] - c[0]) * (b[1] - c[1]) - (b[0] - c[0]) * (a[1] - c[1]);
  const inside = (p) => {
    const d1 = sign(p, last, corners[0]), d2 = sign(p, corners[0], corners[1]), d3 = sign(p, corners[1], last);
    return !((d1 < 0 || d2 < 0 || d3 < 0) && (d1 > 0 || d2 > 0 || d3 > 0));
  };

  const onMove = (e) => {
    if (e.pointerType === 'touch') return;
    const h = header.getBoundingClientRect();
    const p = [e.clientX - h.left, e.clientY - h.top];
    if (header.dataset.mode === 'safe' && last && corners) {
      armed = inside(p);
      tri.setAttribute('points', last.join(',') + ' ' + corners[0].join(',') + ' ' + corners[1].join(','));
      tri.style.opacity = armed ? '1' : '0';
      clearTimeout(guardT);
      guardT = setTimeout(() => { armed = false; tri.style.opacity = '0'; }, guardMs);
    }
    const item = e.target.closest('[data-tmm03-item]');
    if (item && !armed && !item.hasAttribute('data-open')) openItem(item);
    last = p;
  };
  const onLeave = (e) => {
    if (e.relatedTarget && header.contains(e.relatedTarget)) return;
    if (header.contains(document.activeElement)) return;
    clearTimeout(guardT); armed = false; last = null; tri.style.opacity = '0';
    nav.querySelectorAll('[data-tmm03-item][data-open]').forEach((i) => setOpen(i, false));
  };
  const onClick = (e) => {
    const t = e.target.closest('[data-tmm03-trigger]');
    if (!t) return;
    const item = t.closest('[data-tmm03-item]');
    if (item.hasAttribute('data-open') && e.pointerType !== 'mouse') setOpen(item, false); else openItem(item);
  };
  const onKey = (e) => {
    if (e.key !== 'Escape') return;
    const open = nav.querySelector('[data-tmm03-item][data-open]');
    if (!open) return;
    setOpen(open, false);
    open.querySelector('[data-tmm03-trigger]').focus();
  };
  const onResize = () => { const open = nav.querySelector('[data-tmm03-item][data-open]'); if (open) openItem(open); };

  header.addEventListener('pointermove', onMove);
  header.addEventListener('pointerleave', onLeave);
  nav.addEventListener('click', onClick);
  nav.addEventListener('keydown', onKey);
  window.addEventListener('resize', onResize);
  root.__tmmCleanup = () => {
    header.removeEventListener('pointermove', onMove);
    header.removeEventListener('pointerleave', onLeave);
    nav.removeEventListener('click', onClick);
    nav.removeEventListener('keydown', onKey);
    window.removeEventListener('resize', onResize);
    clearTimeout(guardT);
  };
})();

Setup — do this once per project

Skip this if your project already runs Tailwind v4.

1Load Tailwind
<script src="https://cdn.jsdelivr.net/npm/@tailwindcss/browser@4"></script>

Compiles in the browser — perfect for a CodePen or a quick test, not for production.

2Add the stylesheetRequiredthe @theme block is what makes the custom utilities exist
@import "tailwindcss";

@theme {
  --color-tmm03-bg: #17140f;
  --color-tmm03-bg: oklch(0.19 0.012 75);
  --color-tmm03-surf: #211c15;
  --color-tmm03-surf: oklch(0.23 0.015 75);
  --color-tmm03-panel: #f7f2e8;
  --color-tmm03-panel: oklch(0.96 0.014 85);
  --color-tmm03-onpanel: #1c1710;
  --color-tmm03-onpanel: oklch(0.21 0.015 75);
  --color-tmm03-line: #362e22;
  --color-tmm03-line: oklch(0.31 0.022 75);
  --color-tmm03-ink: #f3ede1;
  --color-tmm03-ink: oklch(0.95 0.015 85);
  --color-tmm03-mut: #ab9d86;
  --color-tmm03-mut: oklch(0.71 0.035 80);
  --color-tmm03-acc: #f2a63b;
  --color-tmm03-acc: oklch(0.77 0.15 70);
  --color-tmm03-on-acc: #12100e;
  --color-tmm03-on-acc: oklch(0.17 0.006 70);
  --color-tmm03-ok: #3fae6a;
  --color-tmm03-ok: oklch(0.67 0.14 150);
  --font-tmm03-sans: 'IBM Plex Sans', system-ui, sans-serif;
  --font-tmm03-mono: 'IBM Plex Mono', ui-monospace, monospace;
  --shadow-tmm03-panel: 0 30px 60px -30px rgb(0 0 0 / 0.7);
}
/* The open state as ONE variant: focus-within or a scripted [data-open] (hover is driven by the script).
   Every panel, chevron and entry utility reads tmm03-open: instead of a repeated selector list. */

@custom-variant tmm03-open {
  &:where([data-tmm03-item]:is(:focus-within, [data-open]) *) {
    @slot;
  }
}
/* Root rule: the full-bleed contract, sized before the browser build compiles. */

.tmm-03 {
  width: 100%;
  min-height: 100svh;
}
/* Theme toggle: the checkbox flips the token set; the OS preference flips the default. */

.tmm-03:has(#tmm03-theme:checked) {
  --color-tmm03-bg: #f6f3ec;
  --color-tmm03-bg: oklch(0.96 0.01 85);
  --color-tmm03-surf: #ffffff;
  --color-tmm03-surf: oklch(1 0 0);
  --color-tmm03-panel: #1c1710;
  --color-tmm03-panel: oklch(0.21 0.015 75);
  --color-tmm03-onpanel: #f7f2e8;
  --color-tmm03-onpanel: oklch(0.96 0.014 85);
  --color-tmm03-line: #ddd4c2;
  --color-tmm03-line: oklch(0.87 0.025 85);
  --color-tmm03-ink: #1c1710;
  --color-tmm03-ink: oklch(0.21 0.015 75);
  --color-tmm03-mut: #6a5f50;
  --color-tmm03-mut: oklch(0.48 0.03 75);
  --color-tmm03-acc: #a1560a;
  --color-tmm03-acc: oklch(0.52 0.14 60);
  --color-tmm03-on-acc: #ffffff;
  --color-tmm03-on-acc: oklch(1 0 0);
  --color-tmm03-ok: #2f8f55;
  --color-tmm03-ok: oklch(0.58 0.13 150);
}

@media (prefers-color-scheme: light) {
  .tmm-03 {
    --color-tmm03-bg: #f6f3ec;
    --color-tmm03-bg: oklch(0.96 0.01 85);
    --color-tmm03-surf: #ffffff;
    --color-tmm03-surf: oklch(1 0 0);
    --color-tmm03-panel: #1c1710;
    --color-tmm03-panel: oklch(0.21 0.015 75);
    --color-tmm03-onpanel: #f7f2e8;
    --color-tmm03-onpanel: oklch(0.96 0.014 85);
    --color-tmm03-line: #ddd4c2;
    --color-tmm03-line: oklch(0.87 0.025 85);
    --color-tmm03-ink: #1c1710;
    --color-tmm03-ink: oklch(0.21 0.015 75);
    --color-tmm03-mut: #6a5f50;
    --color-tmm03-mut: oklch(0.48 0.03 75);
    --color-tmm03-acc: #a1560a;
    --color-tmm03-acc: oklch(0.52 0.14 60);
    --color-tmm03-on-acc: #ffffff;
    --color-tmm03-on-acc: oklch(1 0 0);
    --color-tmm03-ok: #2f8f55;
    --color-tmm03-ok: oklch(0.58 0.13 150);
  }

  .tmm-03:has(#tmm03-theme:checked) {
    --color-tmm03-bg: #17140f;
    --color-tmm03-bg: oklch(0.19 0.012 75);
    --color-tmm03-surf: #211c15;
    --color-tmm03-surf: oklch(0.23 0.015 75);
    --color-tmm03-panel: #f7f2e8;
    --color-tmm03-panel: oklch(0.96 0.014 85);
    --color-tmm03-onpanel: #1c1710;
    --color-tmm03-onpanel: oklch(0.21 0.015 75);
    --color-tmm03-line: #362e22;
    --color-tmm03-line: oklch(0.31 0.022 75);
    --color-tmm03-ink: #f3ede1;
    --color-tmm03-ink: oklch(0.95 0.015 85);
    --color-tmm03-mut: #ab9d86;
    --color-tmm03-mut: oklch(0.71 0.035 80);
    --color-tmm03-acc: #f2a63b;
    --color-tmm03-acc: oklch(0.77 0.15 70);
    --color-tmm03-on-acc: #12100e;
    --color-tmm03-on-acc: oklch(0.17 0.006 70);
    --color-tmm03-ok: #3fae6a;
    --color-tmm03-ok: oklch(0.67 0.14 150);
  }
}
3Fonts used by this demooptional — skip if you have your own type stack
<link rel="preconnect" href="https://fonts.googleapis.com">
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
<link rel="stylesheet" href="https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500;600;700&family=IBM+Plex+Sans:wght@400;500;600;700&display=swap">

What changed in the port

Which parts became utilities, which stayed CSS, and why.

  • Class toggles became data-open; the triangle polygon is found by [data-tmm03-tri], so renaming styles can never break the script.
  • .mm-03__tri { fill: color-mix(...) } became fill-tmm03-acc/20 — the opacity modifier works on SVG paint utilities too.
  • UI upgrade: clicking a trigger now opens it (the original only opened on move, so a keyboard Enter or touch tap did nothing beyond focus); touch moves are ignored by the triangle.
  • UI upgrade: panels gained a caret pointing at their trigger, a count chip in the panel head, and a live pulse on the realtime row; muted copy raised to 4.5:1 in both themes.
Paste this into ChatGPT, Claude, Cursor, or any coding assistant. The block below is pre-framed with everything the AI needs to integrate this demo into your project — markup, styles, scoping notes, and the source URL. Hit Copy and paste straight into your chat.
Here's a working CSS demo from CodeFronts. Use it as-is or adapt to your framework. All classes are scoped under a unique prefix so the code won't collide with your existing styles. MIT licensed.
Demo: Tailwind Mega Menu Safe Triangle (Diagonal Hover Fix)
Source: https://codefronts.com/navigation/tailwind-css-mega-menus/tailwind-mega-menu-safe-triangle-diagonal-hover/

The diagonal-pointer problem, solved the way big retailers do it: while the pointer is travelling inside the triangle between its last position and the open panel's top corners, neighbouring triggers are ignored. A fleet-operations console draws the live triangle in a dashed SVG overlay so you can watch it work. State is a data-open attribute; every visual is a tmm03-open: utility, including the left-to-right row wipe.
## HTML
```html
<section class="tmm-03 relative w-full min-h-svh bg-tmm03-bg bg-[radial-gradient(60rem_28rem_at_82%_-10%,color-mix(in_oklab,var(--color-tmm03-acc)_16%,transparent),transparent_62%)] font-tmm03-sans leading-normal text-tmm03-ink [&_:focus-visible]:rounded-[4px] [&_:focus-visible]:outline-2 [&_:focus-visible]:outline-offset-3 [&_:focus-visible]:outline-tmm03-acc" aria-labelledby="tmm03-title">
  <h2 class="sr-only" id="tmm03-title">Vale Logistics operations console</h2>

  <div class="absolute top-3 right-[clamp(0.75rem,3vw,1.5rem)] z-60">
    <input class="peer absolute inset-0 m-0 size-full cursor-pointer opacity-0" type="checkbox" id="tmm03-theme">
    <label class="grid size-11 cursor-pointer place-items-center rounded-[4px] border border-tmm03-line bg-tmm03-surf text-tmm03-ink peer-focus-visible:outline-2 peer-focus-visible:outline-offset-3 peer-focus-visible:outline-tmm03-acc" for="tmm03-theme">
      <svg class="size-5" viewBox="0 0 24 24" aria-hidden="true" focusable="false"><circle cx="12" cy="12" r="8.5" fill="none" stroke="currentColor" stroke-width="1.6"/><path d="M12 3.5a8.5 8.5 0 0 0 0 17Z" fill="currentColor"/></svg>
      <span class="sr-only">Toggle dark theme</span>
    </label>
  </div>

  <header data-tmm03-header data-mode="safe" data-guard="320" class="relative z-10 w-full border-b border-tmm03-line bg-tmm03-surf pb-[clamp(11rem,26vw,14rem)] max-[52rem]:pb-0">
    <svg class="pointer-events-none absolute inset-0 z-40 size-full max-[52rem]:hidden" aria-hidden="true" focusable="false"><polygon data-tmm03-tri class="fill-tmm03-acc/20 stroke-tmm03-acc stroke-[1.5] opacity-0 transition-opacity duration-100 [stroke-dasharray:5_4]" points=""></polygon></svg>

    <div class="mx-auto flex min-h-15 w-[min(84rem,calc(100%-2rem))] flex-wrap items-center gap-x-[clamp(0.5rem,2vw,2rem)] pr-15 max-[52rem]:flex-col max-[52rem]:items-stretch max-[52rem]:py-2.5">
      <a class="inline-flex items-center gap-2 font-tmm03-mono text-[0.95rem]/none font-bold tracking-[0.06em] text-tmm03-ink uppercase" href="#tmm03-title">
        <svg class="size-[22px] text-tmm03-acc" viewBox="0 0 24 24" aria-hidden="true" focusable="false"><path d="M2 16V8h11v8Zm11-5h4l3 3.2V16h-7Z" fill="none" stroke="currentColor" stroke-width="1.7" stroke-linejoin="round"/><circle cx="7" cy="18" r="1.8" fill="currentColor"/><circle cx="17" cy="18" r="1.8" fill="currentColor"/></svg>
        Vale <span class="font-normal text-tmm03-mut">Logistics</span>
      </a>

      <nav data-tmm03-nav class="min-w-0" aria-label="Primary">
        <ul class="flex flex-wrap gap-1 max-[52rem]:flex-col">
          <li data-tmm03-item class="relative">
            <button data-tmm03-trigger type="button" aria-expanded="false" aria-controls="tmm03-panel-fleet" class="inline-flex min-h-11 cursor-pointer items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink transition-colors hover:text-tmm03-acc tmm03-open:bg-tmm03-acc tmm03-open:text-tmm03-on-acc!">Fleet</button>
            <div data-tmm03-panel class="invisible absolute top-full left-0 z-30 mt-2 w-[min(34rem,calc(100vw-3rem))] -translate-y-1.5 rounded-[4px] bg-tmm03-panel p-[clamp(0.85rem,2.4vw,1.15rem)] text-tmm03-onpanel opacity-0 shadow-tmm03-panel pointer-events-none transition-[opacity,translate,visibility] duration-150 before:absolute before:-top-1.5 before:left-6 before:size-3 before:rotate-45 before:rounded-[2px] before:bg-tmm03-panel tmm03-open:visible tmm03-open:translate-y-0 tmm03-open:opacity-100 tmm03-open:pointer-events-auto motion-reduce:transition-none max-[60rem]:w-[min(21rem,calc(100vw-3rem))] max-[52rem]:static max-[52rem]:hidden max-[52rem]:w-full max-[52rem]:visible max-[52rem]:translate-y-0 max-[52rem]:opacity-100 max-[52rem]:before:hidden max-[52rem]:tmm03-open:block" id="tmm03-panel-fleet" aria-label="Fleet">
              <p class="mb-2.5 flex items-baseline justify-between gap-3 font-tmm03-mono text-[0.7rem]/none font-bold tracking-[0.14em] uppercase">Fleet operations <span class="shrink-0 whitespace-nowrap rounded-full bg-tmm03-onpanel/8 px-2 py-1 font-normal tracking-[0.06em] normal-case">14 tools &middot; 212 depots</span></p>
              <ul class="grid grid-cols-2 gap-0.5 max-[52rem]:grid-cols-1">
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-20 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Live vehicle map</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65"><span aria-hidden="true" class="relative size-1.5 rounded-full bg-tmm03-ok before:absolute before:inset-0 before:animate-ping before:rounded-full before:bg-tmm03-ok motion-reduce:before:hidden"></span>realtime</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-60 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Route planner</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">beta</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-100 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Driver hours</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">compliance</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-140 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Maintenance queue</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">32 open</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-180 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Fuel and charging</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">daily</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-220 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Depot capacity</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">weekly</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-260 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Incident reports</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">archive</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-300 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Cost per mile</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">finance</span></a></li>
              </ul>
            </div>
          </li>

          <li data-tmm03-item class="relative">
            <button data-tmm03-trigger type="button" aria-expanded="false" aria-controls="tmm03-panel-network" class="inline-flex min-h-11 cursor-pointer items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink transition-colors hover:text-tmm03-acc tmm03-open:bg-tmm03-acc tmm03-open:text-tmm03-on-acc!">Network</button>
            <div data-tmm03-panel class="invisible absolute top-full left-0 z-30 mt-2 w-[min(34rem,calc(100vw-3rem))] -translate-y-1.5 rounded-[4px] bg-tmm03-panel p-[clamp(0.85rem,2.4vw,1.15rem)] text-tmm03-onpanel opacity-0 shadow-tmm03-panel pointer-events-none transition-[opacity,translate,visibility] duration-150 before:absolute before:-top-1.5 before:left-6 before:size-3 before:rotate-45 before:rounded-[2px] before:bg-tmm03-panel tmm03-open:visible tmm03-open:translate-y-0 tmm03-open:opacity-100 tmm03-open:pointer-events-auto motion-reduce:transition-none max-[60rem]:w-[min(21rem,calc(100vw-3rem))] max-[52rem]:static max-[52rem]:hidden max-[52rem]:w-full max-[52rem]:visible max-[52rem]:translate-y-0 max-[52rem]:opacity-100 max-[52rem]:before:hidden max-[52rem]:tmm03-open:block" id="tmm03-panel-network" aria-label="Network">
              <p class="mb-2.5 flex items-baseline justify-between gap-3 font-tmm03-mono text-[0.7rem]/none font-bold tracking-[0.14em] uppercase">Network <span class="shrink-0 whitespace-nowrap rounded-full bg-tmm03-onpanel/8 px-2 py-1 font-normal tracking-[0.06em] normal-case">6 tools</span></p>
              <ul class="grid grid-cols-2 gap-0.5 max-[52rem]:grid-cols-1">
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-20 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Depot directory</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">212 sites</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-60 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Partner carriers</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">contracts</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-100 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Coverage gaps</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">planning</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-140 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Service levels</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">SLA</span></a></li>
              </ul>
            </div>
          </li>

          <li data-tmm03-item class="relative">
            <button data-tmm03-trigger type="button" aria-expanded="false" aria-controls="tmm03-panel-reports" class="inline-flex min-h-11 cursor-pointer items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink transition-colors hover:text-tmm03-acc tmm03-open:bg-tmm03-acc tmm03-open:text-tmm03-on-acc!">Reports</button>
            <div data-tmm03-panel class="invisible absolute top-full left-0 z-30 mt-2 w-[min(34rem,calc(100vw-3rem))] -translate-y-1.5 rounded-[4px] bg-tmm03-panel p-[clamp(0.85rem,2.4vw,1.15rem)] text-tmm03-onpanel opacity-0 shadow-tmm03-panel pointer-events-none transition-[opacity,translate,visibility] duration-150 before:absolute before:-top-1.5 before:left-6 before:size-3 before:rotate-45 before:rounded-[2px] before:bg-tmm03-panel tmm03-open:visible tmm03-open:translate-y-0 tmm03-open:opacity-100 tmm03-open:pointer-events-auto motion-reduce:transition-none max-[60rem]:w-[min(21rem,calc(100vw-3rem))] max-[52rem]:static max-[52rem]:hidden max-[52rem]:w-full max-[52rem]:visible max-[52rem]:translate-y-0 max-[52rem]:opacity-100 max-[52rem]:before:hidden max-[52rem]:tmm03-open:block" id="tmm03-panel-reports" aria-label="Reports">
              <p class="mb-2.5 flex items-baseline justify-between gap-3 font-tmm03-mono text-[0.7rem]/none font-bold tracking-[0.14em] uppercase">Reports <span class="shrink-0 whitespace-nowrap rounded-full bg-tmm03-onpanel/8 px-2 py-1 font-normal tracking-[0.06em] normal-case">9 tools</span></p>
              <ul class="grid grid-cols-2 gap-0.5 max-[52rem]:grid-cols-1">
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-20 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Weekly summary</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">PDF</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-60 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Utilisation</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">dashboard</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-100 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Emissions</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">export</span></a></li>
                <li class="[clip-path:inset(0_100%_0_0)] opacity-0 transition-[clip-path,opacity] duration-[240ms,100ms] ease-linear delay-140 tmm03-open:[clip-path:inset(-8px)] tmm03-open:opacity-100 motion-reduce:[clip-path:none] motion-reduce:opacity-100 motion-reduce:transition-none"><a href="#tmm03-title" class="grid min-h-[46px] min-w-0 content-center gap-0.5 rounded-[3px] px-2 py-1 text-tmm03-onpanel transition-colors hover:bg-tmm03-acc/34"><b class="text-[0.88rem]/tight font-semibold">Custom query</b><span class="inline-flex items-center gap-1.5 font-tmm03-mono text-[0.62rem]/none font-medium tracking-[0.08em] uppercase opacity-65">SQL</span></a></li>
              </ul>
            </div>
          </li>

          <li><a class="inline-flex min-h-11 items-center rounded-[3px] px-3.5 text-[0.88rem]/none font-semibold text-tmm03-ink hover:text-tmm03-acc" href="#tmm03-title">Settings</a></li>
        </ul>
      </nav>

      <div class="ml-auto flex items-center gap-3 max-[52rem]:ml-0">
        <span class="font-tmm03-mono text-[0.72rem]/none font-medium tracking-[0.06em] text-tmm03-mut">Shift B &middot; 06:00&ndash;14:00</span>
        <span class="grid size-8 place-items-center rounded-full bg-tmm03-acc/24 font-tmm03-mono text-[0.72rem]/none font-bold text-tmm03-acc" aria-hidden="true">JL</span>
      </div>
    </div>
  </header>

  <main class="mx-auto w-[min(84rem,calc(100%-2rem))] py-[clamp(1.5rem,5vw,3rem)]">
    <dl class="grid grid-cols-[repeat(auto-fit,minmax(min(100%,13rem),1fr))] overflow-hidden rounded-[4px] border-t border-l border-tmm03-line">
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">Vehicles moving</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums ">1,284</dd><span class="text-[0.76rem] text-tmm03-mut">+3.1% vs yesterday</span></div>
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">On-time rate</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums ">96.4%</dd><span class="text-[0.76rem] text-tmm03-mut">target 95%</span></div>
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">Late at depot</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums text-tmm03-acc">37</dd><span class="text-[0.76rem] text-tmm03-mut">18 flagged for review</span></div>
      <div class="grid min-w-0 gap-0.5 border-r border-b border-tmm03-line bg-tmm03-surf px-4.5 py-4"><dt class="font-tmm03-mono text-[0.66rem]/none font-semibold tracking-[0.16em] text-tmm03-mut uppercase">Cost per mile</dt><dd class="font-tmm03-mono text-[clamp(1.5rem,4vw,2rem)]/none font-bold tracking-[-0.02em] tabular-nums ">&pound;1.06</dd><span class="text-[0.76rem] text-tmm03-mut">&minus;2p this week</span></div>
    </dl>
  </main>
</section>
```
## CSS
```css
@import "tailwindcss";

@theme {
  --color-tmm03-bg: #17140f;
  --color-tmm03-bg: oklch(0.19 0.012 75);
  --color-tmm03-surf: #211c15;
  --color-tmm03-surf: oklch(0.23 0.015 75);
  --color-tmm03-panel: #f7f2e8;
  --color-tmm03-panel: oklch(0.96 0.014 85);
  --color-tmm03-onpanel: #1c1710;
  --color-tmm03-onpanel: oklch(0.21 0.015 75);
  --color-tmm03-line: #362e22;
  --color-tmm03-line: oklch(0.31 0.022 75);
  --color-tmm03-ink: #f3ede1;
  --color-tmm03-ink: oklch(0.95 0.015 85);
  --color-tmm03-mut: #ab9d86;
  --color-tmm03-mut: oklch(0.71 0.035 80);
  --color-tmm03-acc: #f2a63b;
  --color-tmm03-acc: oklch(0.77 0.15 70);
  --color-tmm03-on-acc: #12100e;
  --color-tmm03-on-acc: oklch(0.17 0.006 70);
  --color-tmm03-ok: #3fae6a;
  --color-tmm03-ok: oklch(0.67 0.14 150);
  --font-tmm03-sans: 'IBM Plex Sans', system-ui, sans-serif;
  --font-tmm03-mono: 'IBM Plex Mono', ui-monospace, monospace;
  --shadow-tmm03-panel: 0 30px 60px -30px rgb(0 0 0 / 0.7);
}
/* The open state as ONE variant: focus-within or a scripted [data-open] (hover is driven by the script).
   Every panel, chevron and entry utility reads tmm03-open: instead of a repeated selector list. */

@custom-variant tmm03-open {
  &:where([data-tmm03-item]:is(:focus-within, [data-open]) *) {
    @slot;
  }
}
/* Root rule: the full-bleed contract, sized before the browser build compiles. */

.tmm-03 {
  width: 100%;
  min-height: 100svh;
}
/* Theme toggle: the checkbox flips the token set; the OS preference flips the default. */

.tmm-03:has(#tmm03-theme:checked) {
  --color-tmm03-bg: #f6f3ec;
  --color-tmm03-bg: oklch(0.96 0.01 85);
  --color-tmm03-surf: #ffffff;
  --color-tmm03-surf: oklch(1 0 0);
  --color-tmm03-panel: #1c1710;
  --color-tmm03-panel: oklch(0.21 0.015 75);
  --color-tmm03-onpanel: #f7f2e8;
  --color-tmm03-onpanel: oklch(0.96 0.014 85);
  --color-tmm03-line: #ddd4c2;
  --color-tmm03-line: oklch(0.87 0.025 85);
  --color-tmm03-ink: #1c1710;
  --color-tmm03-ink: oklch(0.21 0.015 75);
  --color-tmm03-mut: #6a5f50;
  --color-tmm03-mut: oklch(0.48 0.03 75);
  --color-tmm03-acc: #a1560a;
  --color-tmm03-acc: oklch(0.52 0.14 60);
  --color-tmm03-on-acc: #ffffff;
  --color-tmm03-on-acc: oklch(1 0 0);
  --color-tmm03-ok: #2f8f55;
  --color-tmm03-ok: oklch(0.58 0.13 150);
}

@media (prefers-color-scheme: light) {
  .tmm-03 {
    --color-tmm03-bg: #f6f3ec;
    --color-tmm03-bg: oklch(0.96 0.01 85);
    --color-tmm03-surf: #ffffff;
    --color-tmm03-surf: oklch(1 0 0);
    --color-tmm03-panel: #1c1710;
    --color-tmm03-panel: oklch(0.21 0.015 75);
    --color-tmm03-onpanel: #f7f2e8;
    --color-tmm03-onpanel: oklch(0.96 0.014 85);
    --color-tmm03-line: #ddd4c2;
    --color-tmm03-line: oklch(0.87 0.025 85);
    --color-tmm03-ink: #1c1710;
    --color-tmm03-ink: oklch(0.21 0.015 75);
    --color-tmm03-mut: #6a5f50;
    --color-tmm03-mut: oklch(0.48 0.03 75);
    --color-tmm03-acc: #a1560a;
    --color-tmm03-acc: oklch(0.52 0.14 60);
    --color-tmm03-on-acc: #ffffff;
    --color-tmm03-on-acc: oklch(1 0 0);
    --color-tmm03-ok: #2f8f55;
    --color-tmm03-ok: oklch(0.58 0.13 150);
  }

  .tmm-03:has(#tmm03-theme:checked) {
    --color-tmm03-bg: #17140f;
    --color-tmm03-bg: oklch(0.19 0.012 75);
    --color-tmm03-surf: #211c15;
    --color-tmm03-surf: oklch(0.23 0.015 75);
    --color-tmm03-panel: #f7f2e8;
    --color-tmm03-panel: oklch(0.96 0.014 85);
    --color-tmm03-onpanel: #1c1710;
    --color-tmm03-onpanel: oklch(0.21 0.015 75);
    --color-tmm03-line: #362e22;
    --color-tmm03-line: oklch(0.31 0.022 75);
    --color-tmm03-ink: #f3ede1;
    --color-tmm03-ink: oklch(0.95 0.015 85);
    --color-tmm03-mut: #ab9d86;
    --color-tmm03-mut: oklch(0.71 0.035 80);
    --color-tmm03-acc: #f2a63b;
    --color-tmm03-acc: oklch(0.77 0.15 70);
    --color-tmm03-on-acc: #12100e;
    --color-tmm03-on-acc: oklch(0.17 0.006 70);
    --color-tmm03-ok: #3fae6a;
    --color-tmm03-ok: oklch(0.67 0.14 150);
  }
}
```

## JavaScript
```js
(() => {
  const root = document.querySelector('.tmm-03');
  if (!root || root.__tmmCleanup) return;
  const header = root.querySelector('[data-tmm03-header]');
  const nav = root.querySelector('[data-tmm03-nav]');
  const tri = root.querySelector('[data-tmm03-tri]');
  const guardMs = Number(header.dataset.guard || 320);
  let last = null, corners = null, guardT = 0, armed = false;

  const setOpen = (item, on) => {
    item.toggleAttribute('data-open', on);
    item.querySelector('[data-tmm03-trigger]').setAttribute('aria-expanded', String(on));
  };
  const openItem = (item) => {
    nav.querySelectorAll('[data-tmm03-item][data-open]').forEach((i) => { if (i !== item) setOpen(i, false); });
    setOpen(item, true);
    const r = item.querySelector('[data-tmm03-panel]').getBoundingClientRect();
    const h = header.getBoundingClientRect();
    corners = [[r.left - h.left, r.top - h.top], [r.right - h.left, r.top - h.top]];
  };
  const sign = (a, b, c) => (a[0] - c[0]) * (b[1] - c[1]) - (b[0] - c[0]) * (a[1] - c[1]);
  const inside = (p) => {
    const d1 = sign(p, last, corners[0]), d2 = sign(p, corners[0], corners[1]), d3 = sign(p, corners[1], last);
    return !((d1 < 0 || d2 < 0 || d3 < 0) && (d1 > 0 || d2 > 0 || d3 > 0));
  };

  const onMove = (e) => {
    if (e.pointerType === 'touch') return;
    const h = header.getBoundingClientRect();
    const p = [e.clientX - h.left, e.clientY - h.top];
    if (header.dataset.mode === 'safe' && last && corners) {
      armed = inside(p);
      tri.setAttribute('points', last.join(',') + ' ' + corners[0].join(',') + ' ' + corners[1].join(','));
      tri.style.opacity = armed ? '1' : '0';
      clearTimeout(guardT);
      guardT = setTimeout(() => { armed = false; tri.style.opacity = '0'; }, guardMs);
    }
    const item = e.target.closest('[data-tmm03-item]');
    if (item && !armed && !item.hasAttribute('data-open')) openItem(item);
    last = p;
  };
  const onLeave = (e) => {
    if (e.relatedTarget && header.contains(e.relatedTarget)) return;
    if (header.contains(document.activeElement)) return;
    clearTimeout(guardT); armed = false; last = null; tri.style.opacity = '0';
    nav.querySelectorAll('[data-tmm03-item][data-open]').forEach((i) => setOpen(i, false));
  };
  const onClick = (e) => {
    const t = e.target.closest('[data-tmm03-trigger]');
    if (!t) return;
    const item = t.closest('[data-tmm03-item]');
    if (item.hasAttribute('data-open') && e.pointerType !== 'mouse') setOpen(item, false); else openItem(item);
  };
  const onKey = (e) => {
    if (e.key !== 'Escape') return;
    const open = nav.querySelector('[data-tmm03-item][data-open]');
    if (!open) return;
    setOpen(open, false);
    open.querySelector('[data-tmm03-trigger]').focus();
  };
  const onResize = () => { const open = nav.querySelector('[data-tmm03-item][data-open]'); if (open) openItem(open); };

  header.addEventListener('pointermove', onMove);
  header.addEventListener('pointerleave', onLeave);
  nav.addEventListener('click', onClick);
  nav.addEventListener('keydown', onKey);
  window.addEventListener('resize', onResize);
  root.__tmmCleanup = () => {
    header.removeEventListener('pointermove', onMove);
    header.removeEventListener('pointerleave', onLeave);
    nav.removeEventListener('click', onClick);
    nav.removeEventListener('keydown', onKey);
    window.removeEventListener('resize', onResize);
    clearTimeout(guardT);
  };
})();
```

How this works

Why the triangle exists. A panel anchored under the first trigger is wider than the trigger. To reach its right-hand links the pointer moves diagonally — across the second trigger. Naive hover opens the second panel and the user loses the first. The fix is to ignore item changes while the pointer is plausibly heading towards the open panel.

Script owns hover, CSS owns rendering. The variant is built without a hover slot; the script decides when data-open moves. Everything else — trigger fill, fade, row wipe, caret — is declared in the class list.

Arbitrary properties for the wipe. Tailwind has no clip-path scale, so [clip-path:inset(0_100%_0_0)] holds the closed state and tmm03-open:[clip-path:inset(-8px)] the open one; underscores become spaces at compile time.

Make it yours

  • Turn the triangle off: set data-mode="off" on the header to compare naive hover.
  • Hide the visualisation in production: delete the <svg> — the logic does not depend on it.
  • Guard length: data-guard="200" for faster recovery, 500 for slower pointers.

Gotchas — read before shipping

  • The header needs room beneath the bar (pb-[clamp(11rem,26vw,14rem)]) only because this demo's panels are anchored inside it; remove it in a real layout.
  • Skip pointermove for pointerType === 'touch' — touch has no diagonal problem and the triangle math would fight taps.
  • Recompute corners on resize, or the triangle points at where the panel used to be.

Browser support

ChromeSafariFirefoxEdge
111+16.4+128+111+

Tailwind v4 floor (cascade layers, @property, color-mix()). clip-path: inset() transitions are universal at this floor.

Techniques used in this demo

Arbitraryneeds bracket syntax

clip-pathtw ↗

HTML & JSno Tailwind involved

pointer eventsMDN ↗

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