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CSS

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HTML 

              
                <div class="tablist-wrapper">
  <div class="tablist" role="tablist">
    <button class="tab" role="tab" aria-selected="true" tab-index="0">Tab one</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab two</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab three</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab four</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab five</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab six</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab seven</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab eight</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab nine</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab ten</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab eleven</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab twelve</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab thirteen</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab fourteen</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab fifteen</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab sixteen</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab seventeen</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab eighteen</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab nineteen</button>
    <button class="tab" role="tab" aria-selected="false" tabindex="-1">Tab twenty</button>
  </div>
  <div class="indicator"></div>
</div>

<p>See <a href="https://philparsons.co.uk/blog/building-scrollable-tabs-with-css/">this post</a> for an explanation of the example above.</p>
!

CSS 

              
                :root {
  color-scheme: light dark;
}

.tablist-wrapper {
  margin: 3rem auto;
  max-width: 600px;
  overflow: hidden;
  padding: 0 2rem;
  position: relative;
}

.tablist {
  anchor-name: --tab-list;
  background: var(--color-bg-secondary);
  display: flex;
  gap: 0.125rem;
  overflow-x: auto;
  scrollbar-width: none;
  scroll-behavior: smooth;

  &::scroll-button(*) {
    align-self: anchor-center;
    background: var(--color-bg-secondary);
    border: none;
    border-bottom: 2px solid var(--color-bg-secondary);
    font-size: 1rem;
    line-height: 1;
    padding: 0.75rem 0.5rem;
    position: absolute;
    position-anchor: --tab-list;
    width: 2rem;
    z-index: 2;
  }

  &::scroll-button(inline-start) {
    content: "<" / "Previous";
    left: calc(anchor(start) - 2rem);
  }

  &::scroll-button(inline-end) {
    content: ">" / "Next";
    right: calc(anchor(end) - 2rem);
  }
}

.tab {
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 0.75rem 1rem;
  text-transform: uppercase;
  white-space: nowrap;

  &[aria-selected="true"] {
    anchor-name: --selected-tab;
    color: light-dark(rgb(18, 92, 165), rgb(144, 202, 249));
  }

  &:focus-visible {
    background: light-dark(rgb(0 0 0 / 5%), rgb(255 255 255 / 8%));
    outline: 0;
  }
}

.indicator {
  background: light-dark(rgb(25, 118, 210), rgb(144, 202, 249));
  bottom: anchor(bottom);
  height: 2px;
  left: anchor(start);
  right: anchor(end);
  position: absolute;
  position-anchor: --selected-tab;
  transition: left 0.3s ease-in-out, right 0.3s ease-in-out;
  z-index: 1;
}

p {
  margin: 0;
  padding: 0 1rem 1rem;
  text-align: center;
}
!

JS 

              
                const tabList = document.querySelector(".tablist");
const tabs = document.querySelectorAll(".tab");

tabList.addEventListener("click", (e) => {
  const targetTab = e.target.closest('[role="tab"]');
  if (!targetTab) return; // Ignore clicks outside tabs

  // Activate the clicked tab
  activateTab(targetTab);
});

// Add keyboard navigation
tabList.addEventListener("keydown", (e) => {
  const targetTab = e.target;
  const previousTab = targetTab.previousElementSibling;
  const nextTab = targetTab.nextElementSibling;
  const firstTab = tabs[0];
  const lastTab = tabs[tabs.length - 1];

  // Only handle key events if a tab triggered them
  if (targetTab.getAttribute("role") !== "tab") return;

  switch (e.key) {
    case "ArrowLeft":
      e.preventDefault();
      if (previousTab && previousTab.getAttribute("role") === "tab") {
        activateTab(previousTab);
      } else {
        activateTab(lastTab); // Cycle to end
      }
      break;
    case "ArrowRight":
      e.preventDefault();
      if (nextTab && nextTab.getAttribute("role") === "tab") {
        activateTab(nextTab);
      } else {
        activateTab(firstTab); // Cycle to beginning
      }
      break;
    case "Home":
      e.preventDefault();
      activateTab(firstTab);
      break;
    case "End":
      e.preventDefault();
      activateTab(lastTab);
      break;
  }
});

function activateTab(tab) {
  // Deactivate all tabs
  tabs.forEach((t) => {
    t.setAttribute("aria-selected", "false");
    t.setAttribute("tabindex", "-1");
  });

  // Activate the current tab
  tab.setAttribute("aria-selected", "true");
  tab.setAttribute("tabindex", "0");
  tab.focus();
}
!
999px

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