20 CSS Loading Buttons18 / 20

Pure CSSMIT licensed

Full Width Mobile Touch Button

The bottom-anchored primary action: full-bleed, a generous touch target, and a thin indeterminate line along its top edge while the request runs. It respects env(safe-area-inset-bottom) so it clears the home indicator on a notched phone, and it holds its ground at 320px without creating horizontal overflow.

Published

Live Demo
Try it

The code

<div class="lb-18">
  <div class="lb-18__stage">
    <div class="lb-18__phone">
      <div class="lb-18__screen">
        <header class="lb-18__top">
          <span class="lb-18__back" aria-hidden="true">
            <svg viewBox="0 0 20 20" width="16" height="16" fill="none" stroke="currentColor" stroke-width="1.8"><path d="M12 4.5 6.5 10l5.5 5.5"/></svg>
          </span>
          <h2 class="lb-18__h">Review order</h2>
        </header>

        <div class="lb-18__body">
          <div class="lb-18__line"><span>Sourdough loaf ×2</span><span>£9.00</span></div>
          <div class="lb-18__line"><span>Cultured butter</span><span>£4.20</span></div>
          <div class="lb-18__line"><span>Delivery, Thursday</span><span>£2.50</span></div>
          <div class="lb-18__line lb-18__line--total"><span>Total</span><span>£15.70</span></div>
          <p class="lb-18__note">Delivering to Jordan Lee · 14 Ashfield Road</p>
        </div>

        <div class="lb-18__bar">
          <button class="lb-18__cta" type="button" data-state="idle" aria-busy="false">
            <span class="lb-18__line-ind" aria-hidden="true"></span>
            <span class="lb-18__faces">
              <span class="lb-18__face lb-18__face--idle">Place order · £15.70</span>
              <span class="lb-18__face lb-18__face--pending">Processing payment</span>
            </span>
          </button>
          <div class="lb-18__control">
            <input class="lb-18__switch" type="checkbox" id="lb-18-switch">
            <label class="lb-18__lab" for="lb-18-switch">Hold the request open</label>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>
.lb-18 {
  width: 100%;
  min-height: 100vh;
  display: block;
  box-sizing: border-box;
  --bg: #e9efe8;
  --surface: #ffffff;
  --ink: #1c2a20;
  --muted: #63796a;
  --rule: #d7e2d6;
  --accent: #2f6b4a;
  --press: #24523a;
  font-family: ui-sans-serif, system-ui, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--ink);
  padding: 32px 12px;
}

.lb-18 *,
.lb-18 *::before,
.lb-18 *::after {
  box-sizing: border-box;
}

.lb-18__stage {
  display: grid;
  place-items: start center;
  max-inline-size: 100%;
  min-height: calc(100vh - 64px);
}

.lb-18__phone {
  inline-size: 100%;
  max-inline-size: 22rem;
  min-inline-size: 0;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 26px;
  padding: 8px;
  box-shadow: 0 26px 50px -34px rgba(28, 42, 32, .6);
}

.lb-18__screen {
  display: flex;
  flex-direction: column;
  min-block-size: 27rem;
  background: var(--surface);
  border-radius: 20px;
  overflow: hidden;
  min-inline-size: 0;
}

.lb-18__top {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  border-block-end: 1px solid var(--rule);
  min-inline-size: 0;
}

.lb-18__back {
  display: inline-flex;
  color: var(--muted);
  flex: none;
}

.lb-18__h {
  margin: 0;
  font-size: 14.5px;
  font-weight: 620;
  min-inline-size: 0;
}

.lb-18__body {
  flex: 1 1 auto;
  padding: 16px;
  display: grid;
  gap: 10px;
  align-content: start;
  min-inline-size: 0;
}

.lb-18__line {
  display: flex;
  gap: 12px;
  justify-content: space-between;
  font-size: 13px;
  color: var(--muted);
  min-inline-size: 0;
}

.lb-18__line span:first-child {
  min-inline-size: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.lb-18__line span:last-child {
  flex: none;
  font-variant-numeric: tabular-nums;
}

.lb-18__line--total {
  color: var(--ink);
  font-weight: 660;
  font-size: 15px;
  padding-block-start: 10px;
  border-block-start: 1px solid var(--rule);
}

.lb-18__note {
  margin: 6px 0 0;
  font-size: 11.5px;
  color: var(--muted);
  min-inline-size: 0;
}

.lb-18__bar {
  position: sticky;
  inset-block-end: 0;
  background: var(--surface);
  border-block-start: 1px solid var(--rule);
  padding: 12px 14px calc(12px + env(safe-area-inset-bottom, 0px));
  min-inline-size: 0;
}

.lb-18__cta {
  appearance: none;
  position: relative;
  overflow: hidden;
  inline-size: 100%;
  border: 0;
  background: var(--accent);
  color: #f4fbf6;
  border-radius: 14px;
  font: inherit;
  font-size: 14.5px;
  font-weight: 640;
  padding: 0 16px;
  min-block-size: 52px;
  min-inline-size: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 150ms ease;
}

.lb-18__cta:active {
  background: var(--press);
}

.lb-18__cta:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

.lb-18__faces {
  display: grid;
  place-items: center;
  min-inline-size: 0;
}

.lb-18__face {
  grid-area: 1 / 1;
  white-space: nowrap;
  visibility: hidden;
  min-inline-size: 0;
  overflow: hidden;
  text-overflow: ellipsis;
}

.lb-18__face--idle {
  visibility: visible;
}

.lb-18__line-ind {
  position: absolute;
  inset-block-start: 0;
  inset-inline: 0;
  block-size: 2px;
  opacity: 0;
  overflow: hidden;
}

.lb-18__line-ind::before {
  content: "";
  position: absolute;
  inset-block: 0;
  inline-size: 40%;
  background: #f4fbf6;
  animation: lb-18-run 1.1s ease-in-out infinite;
}

@keyframes lb-18-run {
  from {
    transform: translateX(-105%);
  }

  to {
    transform: translateX(290%);
  }
}

.lb-18:has(.lb-18__switch:checked) .lb-18__face--idle {
  visibility: hidden;
}

.lb-18:has(.lb-18__switch:checked) .lb-18__face--pending {
  visibility: visible;
}

.lb-18:has(.lb-18__switch:checked) .lb-18__line-ind {
  opacity: 1;
}

.lb-18:has(.lb-18__switch:checked) .lb-18__cta {
  cursor: progress;
}

.lb-18__control {
  display: flex;
  justify-content: center;
  margin-block-start: 4px;
}

.lb-18__lab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 11.5px;
  color: var(--muted);
  min-height: 44px;
  cursor: pointer;
}

.lb-18__switch {
  accent-color: var(--accent);
  inline-size: 16px;
  block-size: 16px;
  margin: 0;
}

.lb-18__switch:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .lb-18__line-ind::before {
    animation: none;
    inline-size: 100%;
    opacity: .6;
  }

  .lb-18__cta {
    transition: none;
  }
}

@media (prefers-color-scheme: dark) {
  .lb-18 {
    --bg: #0f150f;
    --surface: #171f18;
    --ink: #e6efe6;
    --muted: #93a795;
    --rule: #253026;
    --accent: #47a377;
    --press: #38835e;
  }

  .lb-18__cta {
    color: #0f150f;
  }

  .lb-18__line-ind::before {
    background: #0f150f;
  }
}

[data-theme="dark"] .lb-18 {
  --bg: #0f150f;
  --surface: #171f18;
  --ink: #e6efe6;
  --muted: #93a795;
  --rule: #253026;
  --accent: #47a377;
  --press: #38835e;
}
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 Loading Button 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: Full Width Mobile Touch Button
Source: https://codefronts.com/components/css-loading-buttons/full-width-mobile-touch-button/

The bottom-anchored primary action: full-bleed, a generous touch target, and a thin indeterminate line along its top edge while the request runs. It respects env(safe-area-inset-bottom) so it clears the home indicator on a notched phone, and it holds its ground at 320px without creating horizontal overflow.
## HTML
```html
<div class="lb-18">
  <div class="lb-18__stage">
    <div class="lb-18__phone">
      <div class="lb-18__screen">
        <header class="lb-18__top">
          <span class="lb-18__back" aria-hidden="true">
            <svg viewBox="0 0 20 20" width="16" height="16" fill="none" stroke="currentColor" stroke-width="1.8"><path d="M12 4.5 6.5 10l5.5 5.5"/></svg>
          </span>
          <h2 class="lb-18__h">Review order</h2>
        </header>

        <div class="lb-18__body">
          <div class="lb-18__line"><span>Sourdough loaf ×2</span><span>£9.00</span></div>
          <div class="lb-18__line"><span>Cultured butter</span><span>£4.20</span></div>
          <div class="lb-18__line"><span>Delivery, Thursday</span><span>£2.50</span></div>
          <div class="lb-18__line lb-18__line--total"><span>Total</span><span>£15.70</span></div>
          <p class="lb-18__note">Delivering to Jordan Lee · 14 Ashfield Road</p>
        </div>

        <div class="lb-18__bar">
          <button class="lb-18__cta" type="button" data-state="idle" aria-busy="false">
            <span class="lb-18__line-ind" aria-hidden="true"></span>
            <span class="lb-18__faces">
              <span class="lb-18__face lb-18__face--idle">Place order · £15.70</span>
              <span class="lb-18__face lb-18__face--pending">Processing payment</span>
            </span>
          </button>
          <div class="lb-18__control">
            <input class="lb-18__switch" type="checkbox" id="lb-18-switch">
            <label class="lb-18__lab" for="lb-18-switch">Hold the request open</label>
          </div>
        </div>
      </div>
    </div>
  </div>
</div>
```
## CSS
```css
.lb-18 {
  width: 100%;
  min-height: 100vh;
  display: block;
  box-sizing: border-box;
  --bg: #e9efe8;
  --surface: #ffffff;
  --ink: #1c2a20;
  --muted: #63796a;
  --rule: #d7e2d6;
  --accent: #2f6b4a;
  --press: #24523a;
  font-family: ui-sans-serif, system-ui, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--ink);
  padding: 32px 12px;
}

.lb-18 *,
.lb-18 *::before,
.lb-18 *::after {
  box-sizing: border-box;
}

.lb-18__stage {
  display: grid;
  place-items: start center;
  max-inline-size: 100%;
  min-height: calc(100vh - 64px);
}

.lb-18__phone {
  inline-size: 100%;
  max-inline-size: 22rem;
  min-inline-size: 0;
  background: var(--surface);
  border: 1px solid var(--rule);
  border-radius: 26px;
  padding: 8px;
  box-shadow: 0 26px 50px -34px rgba(28, 42, 32, .6);
}

.lb-18__screen {
  display: flex;
  flex-direction: column;
  min-block-size: 27rem;
  background: var(--surface);
  border-radius: 20px;
  overflow: hidden;
  min-inline-size: 0;
}

.lb-18__top {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 14px 16px;
  border-block-end: 1px solid var(--rule);
  min-inline-size: 0;
}

.lb-18__back {
  display: inline-flex;
  color: var(--muted);
  flex: none;
}

.lb-18__h {
  margin: 0;
  font-size: 14.5px;
  font-weight: 620;
  min-inline-size: 0;
}

.lb-18__body {
  flex: 1 1 auto;
  padding: 16px;
  display: grid;
  gap: 10px;
  align-content: start;
  min-inline-size: 0;
}

.lb-18__line {
  display: flex;
  gap: 12px;
  justify-content: space-between;
  font-size: 13px;
  color: var(--muted);
  min-inline-size: 0;
}

.lb-18__line span:first-child {
  min-inline-size: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.lb-18__line span:last-child {
  flex: none;
  font-variant-numeric: tabular-nums;
}

.lb-18__line--total {
  color: var(--ink);
  font-weight: 660;
  font-size: 15px;
  padding-block-start: 10px;
  border-block-start: 1px solid var(--rule);
}

.lb-18__note {
  margin: 6px 0 0;
  font-size: 11.5px;
  color: var(--muted);
  min-inline-size: 0;
}

.lb-18__bar {
  position: sticky;
  inset-block-end: 0;
  background: var(--surface);
  border-block-start: 1px solid var(--rule);
  padding: 12px 14px calc(12px + env(safe-area-inset-bottom, 0px));
  min-inline-size: 0;
}

.lb-18__cta {
  appearance: none;
  position: relative;
  overflow: hidden;
  inline-size: 100%;
  border: 0;
  background: var(--accent);
  color: #f4fbf6;
  border-radius: 14px;
  font: inherit;
  font-size: 14.5px;
  font-weight: 640;
  padding: 0 16px;
  min-block-size: 52px;
  min-inline-size: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background 150ms ease;
}

.lb-18__cta:active {
  background: var(--press);
}

.lb-18__cta:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

.lb-18__faces {
  display: grid;
  place-items: center;
  min-inline-size: 0;
}

.lb-18__face {
  grid-area: 1 / 1;
  white-space: nowrap;
  visibility: hidden;
  min-inline-size: 0;
  overflow: hidden;
  text-overflow: ellipsis;
}

.lb-18__face--idle {
  visibility: visible;
}

.lb-18__line-ind {
  position: absolute;
  inset-block-start: 0;
  inset-inline: 0;
  block-size: 2px;
  opacity: 0;
  overflow: hidden;
}

.lb-18__line-ind::before {
  content: "";
  position: absolute;
  inset-block: 0;
  inline-size: 40%;
  background: #f4fbf6;
  animation: lb-18-run 1.1s ease-in-out infinite;
}

@keyframes lb-18-run {
  from {
    transform: translateX(-105%);
  }

  to {
    transform: translateX(290%);
  }
}

.lb-18:has(.lb-18__switch:checked) .lb-18__face--idle {
  visibility: hidden;
}

.lb-18:has(.lb-18__switch:checked) .lb-18__face--pending {
  visibility: visible;
}

.lb-18:has(.lb-18__switch:checked) .lb-18__line-ind {
  opacity: 1;
}

.lb-18:has(.lb-18__switch:checked) .lb-18__cta {
  cursor: progress;
}

.lb-18__control {
  display: flex;
  justify-content: center;
  margin-block-start: 4px;
}

.lb-18__lab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 11.5px;
  color: var(--muted);
  min-height: 44px;
  cursor: pointer;
}

.lb-18__switch {
  accent-color: var(--accent);
  inline-size: 16px;
  block-size: 16px;
  margin: 0;
}

.lb-18__switch:focus-visible {
  outline: 3px solid var(--accent);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  .lb-18__line-ind::before {
    animation: none;
    inline-size: 100%;
    opacity: .6;
  }

  .lb-18__cta {
    transition: none;
  }
}

@media (prefers-color-scheme: dark) {
  .lb-18 {
    --bg: #0f150f;
    --surface: #171f18;
    --ink: #e6efe6;
    --muted: #93a795;
    --rule: #253026;
    --accent: #47a377;
    --press: #38835e;
  }

  .lb-18__cta {
    color: #0f150f;
  }

  .lb-18__line-ind::before {
    background: #0f150f;
  }
}

[data-theme="dark"] .lb-18 {
  --bg: #0f150f;
  --surface: #171f18;
  --ink: #e6efe6;
  --muted: #93a795;
  --rule: #253026;
  --accent: #47a377;
  --press: #38835e;
}
```

How this works

Full-bleed does not mean edge-to-edge padding. The bar spans the whole inline axis, but its padding uses calc(14px + env(safe-area-inset-bottom, 0px)) so on a phone with a home indicator the button sits above the gesture area instead of under it. Always pass the fallback: on a desktop browser env() resolves to nothing and an unfallbacked calc() invalidates the whole declaration.

sticky beats fixed inside a component. position: fixed escapes to the viewport, which means the bar floats over anything the component is embedded in and ignores its container's bounds. position: sticky with inset-block-end: 0 keeps it inside the phone frame here, and inside a scroll container in a real app.

The progress line lives on the button, not above it. A 2 px absolutely positioned strip on the button's top edge with overflow: hidden on the button clips a sliding gradient into an indeterminate bar. It reads as part of the control rather than as a page-level loader, which is what you want when only this action is pending.

The traps are both about the small screen. A pending label like "Processing payment…" is a long string, and a flex child with the default min-width: auto refuses to shrink below it, pushing the bar past 320px and giving the whole page a horizontal scrollbar — set min-inline-size: 0. And avoid a transform: scale() press effect on touch: on a full-width control the whole bar visibly jumps, which reads as a mis-tap rather than feedback.

Make it yours

  • Change the bar's background to transparent with a blur if the content behind it should show through.
  • Raise the control height to 56px for a thumb-first checkout flow.
  • Move the progress line to the bottom edge by swapping inset-block-start for inset-block-end.
  • Retint --accent to move the button, the line and the focus ring together.
  • Add a secondary text link above the button for the escape route, keeping the primary action alone in the bar.
  • Wire the pending state to data-state from your request handler instead of the checkbox.

Gotchas — read before shipping

  • env(safe-area-inset-bottom) without a fallback value invalidates the whole calc() on browsers that do not define it.
  • position: fixed inside a component escapes its container and overlays whatever the component is embedded in.
  • A long pending label on a flex child with default min-width: auto forces horizontal overflow at 320px.
  • A scale-down press effect on a full-width bar looks like a layout jump on touch rather than feedback.

Browser support

ChromeSafariFirefoxEdge
105+15.4+121+105+

:has() sets the floor because the checkbox drives the pending state — Chrome 105, Safari 15.4, Firefox 121. env() and sticky positioning are supported much earlier; Firefox ignores env() insets on desktop, where they are zero anyway.

Techniques used in this demo

:has()MDN ↗@keyframesMDN ↗place-items / place-contentMDN ↗

Search CodeFronts

Loading…

↑↓ navigate↵ selectesc closeOpen full search page →