.experiment-viewer {
  --experiment-space: 16px;
  --experiment-section-gap: calc(2 * var(--experiment-space));
  --experiment-header-row: 44px;
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100dvh;
  max-width: none;
  max-height: none;
  margin: 0;
  padding: 0;
  border: 0;
  background: var(--background);
  color: var(--foreground);
  overflow: hidden;
}

.experiment-viewer::backdrop { background: transparent; }
.is-viewing-experiment .snap-feed { overflow-y: hidden; }

.experiment-header {
  position: absolute;
  inset: 0 0 auto;
  z-index: 2;
  height: calc(var(--experiment-section-gap) + var(--experiment-header-row) + env(safe-area-inset-top));
  padding-top: calc(var(--experiment-section-gap) + env(safe-area-inset-top));
  background: var(--background);
}

.experiment-header-inner {
  width: min(100% - 48px, var(--content-column));
  height: var(--experiment-header-row);
  margin-inline: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.experiment-collection { font: 500 13px/1.4 var(--font-sans); }

.experiment-icon-button {
  position: relative;
  isolation: isolate;
  display: grid;
  place-items: center;
  flex: 0 0 36px;
  width: 36px;
  height: 36px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  color: var(--muted);
  background: transparent;
  cursor: pointer;
  transition: color 180ms ease-out;
}

.experiment-icon-button:not(.experiment-play)::before {
  content: "";
  position: absolute;
  z-index: -1;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: transparent;
  pointer-events: none;
  transition: background-color 180ms ease-out;
}

.experiment-icon-button:not(.experiment-play):hover:not(:disabled) {
  color: var(--foreground);
}
.experiment-icon-button:not(.experiment-play):hover:not(:disabled)::before {
  background: var(--line);
}

.experiment-icon-button:disabled { opacity: .25; cursor: default; }

.experiment-icon {
  display: block;
  width: 18px;
  height: 18px;
  background: currentColor;
  mask: var(--icon) center / contain no-repeat;
  -webkit-mask: var(--icon) center / contain no-repeat;
}
.icon-close { --icon: url("data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%2224%22%20height%3D%2224%22%20viewBox%3D%220%200%2024%2024%22%20fill%3D%22none%22%20stroke%3D%22currentColor%22%20stroke-width%3D%222%22%20stroke-linecap%3D%22round%22%20stroke-linejoin%3D%22round%22%3E%3Cpath%20d%3D%22M18%206%206%2018%22%20%2F%3E%3Cpath%20d%3D%22m6%206%2012%2012%22%20%2F%3E%3C%2Fsvg%3E"); }
.icon-previous { --icon: url("data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%2224%22%20height%3D%2224%22%20viewBox%3D%220%200%2024%2024%22%20fill%3D%22none%22%20stroke%3D%22currentColor%22%20stroke-width%3D%222%22%20stroke-linecap%3D%22round%22%20stroke-linejoin%3D%22round%22%3E%3Cpath%20d%3D%22m15%2018-6-6%206-6%22%20%2F%3E%3C%2Fsvg%3E"); }
.icon-next { --icon: url("data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%2224%22%20height%3D%2224%22%20viewBox%3D%220%200%2024%2024%22%20fill%3D%22none%22%20stroke%3D%22currentColor%22%20stroke-width%3D%222%22%20stroke-linecap%3D%22round%22%20stroke-linejoin%3D%22round%22%3E%3Cpath%20d%3D%22m9%2018%206-6-6-6%22%20%2F%3E%3C%2Fsvg%3E"); }

.experiment-scroll {
  height: 100%;
  padding-top: calc(2 * var(--experiment-section-gap) + var(--experiment-header-row) + env(safe-area-inset-top));
  padding-bottom: calc(64px + env(safe-area-inset-bottom));
  overflow-y: auto;
  overflow-x: hidden;
  overscroll-behavior: contain;
  scrollbar-width: none;
}

.experiment-track {
  --slide-width: min(592px, calc(100vw - 64px), 68svh);
  position: relative;
  display: flex;
  align-items: center;
  gap: clamp(24px, 6vw, 80px);
  width: 100%;
  padding: 0 calc((100% - var(--slide-width)) / 2);
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scroll-snap-type: x mandatory;
  scrollbar-width: none;
  cursor: grab;
  user-select: none;
  -webkit-user-select: none;
}

.experiment-track::-webkit-scrollbar,
.experiment-scroll::-webkit-scrollbar { display: none; }
.experiment-track.is-dragging { cursor: grabbing; scroll-snap-type: none; }

.experiment-slide {
  position: relative;
  flex: 0 0 var(--slide-width);
  aspect-ratio: 4 / 3;
  min-width: 0;
  border-radius: 16px;
  overflow: hidden;
  background: var(--soft);
  scroll-snap-align: center;
  opacity: .45;
  transform: scale(.88);
  transition: opacity 300ms ease-out, transform 420ms var(--ease-super-out);
}

.experiment-slide.is-current { opacity: 1; transform: scale(1); }
.experiment-slide > img,
.experiment-slide > video {
  position: absolute;
  inset: 0;
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  opacity: 0;
  transition: opacity 180ms ease-out;
}
.experiment-slide.is-loaded > img,
.experiment-slide.is-loaded > video { opacity: 1; }

.experiment-media-state {
  position: absolute;
  inset: 0;
  display: grid;
  place-content: center;
  padding: 24px;
  color: var(--muted);
  font: 400 11px/1.6 var(--font-sans);
  text-align: center;
  pointer-events: none;
}
.experiment-slide.is-loaded:not(.has-error) .experiment-media-state { display: none; }
.experiment-slide.has-error > video,
.experiment-slide.has-error > img { opacity: 0; }

.experiment-play {
  position: absolute;
  right: 12px;
  bottom: 12px;
  z-index: 1;
  color: var(--foreground);
  -webkit-tap-highlight-color: transparent;
  opacity: 0;
  visibility: hidden;
}
.experiment-play .experiment-icon { --icon: url("data:image/svg+xml,%3Csvg%20viewBox%3D%220%200%2024%2024%22%20fill%3D%22currentColor%22%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%3E%3Cpath%20d%3D%22M6%205H8V19H6V5ZM16%205H18V19H16V5Z%22%2F%3E%3C%2Fsvg%3E"); width: 20px; height: 20px; }
.experiment-play.is-paused .experiment-icon { --icon: url("data:image/svg+xml,%3Csvg%20viewBox%3D%220%200%2024%2024%22%20fill%3D%22currentColor%22%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%3E%3Cpath%20d%3D%22M19.376%2012.4161L8.77735%2019.4818C8.54759%2019.635%208.23715%2019.5729%208.08397%2019.3432C8.02922%2019.261%208%2019.1645%208%2019.0658V4.93433C8%204.65818%208.22386%204.43433%208.5%204.43433C8.59871%204.43433%208.69522%204.46355%208.77735%204.5183L19.376%2011.584C19.6057%2011.7372%2019.6678%2012.0477%2019.5146%2012.2774C19.478%2012.3323%2019.4309%2012.3795%2019.376%2012.4161Z%22%2F%3E%3C%2Fsvg%3E"); }
.experiment-slide.is-current .experiment-play { visibility: visible; }
.experiment-slide.is-current:hover .experiment-play,
.experiment-play:focus-visible,
.experiment-slide.is-current .experiment-play.is-paused { opacity: 1; }
.experiment-play[hidden] { display: none; }

.experiment-reading {
  width: min(100% - 48px, var(--content-column));
  margin: var(--experiment-section-gap) auto 0;
}

.experiment-navigation {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: var(--experiment-section-gap);
}

.experiment-dots,
.experiment-arrows { display: flex; align-items: center; }
.experiment-dots {
  flex: 0 0 auto;
  height: 24px;
  padding-inline: 4px;
  background: color-mix(in srgb, var(--foreground) 4%, transparent);
  border-radius: 12px;
  overflow: hidden;
}
.experiment-dots button {
  display: grid;
  place-items: center;
  flex: 0 0 24px;
  width: 24px;
  height: 24px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: transparent;
  cursor: pointer;
}
.experiment-dots button::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--ring);
  transition: background-color 180ms ease-out;
}
.experiment-dots button[aria-pressed="true"]::before,
.experiment-dots button:hover::before { background: var(--foreground); }

.experiment-copy h2 {
  margin: 0;
  max-width: none;
  font: 500 20px/1.25 var(--font-flare);
  overflow-wrap: anywhere;
}
.experiment-category { margin-top: 6px; color: var(--muted); font: 400 13px/1.4 var(--font-sans); }
.experiment-description { margin-top: var(--experiment-space); color: var(--body-text); font: 400 15px/1.6 var(--font-flare); }
html[lang="zh-CN"] .experiment-description { line-height: 1.65; }

.experiment-viewer :focus-visible { outline: 2px solid var(--ring); outline-offset: 3px; }
.experiment-dots button:focus-visible { outline-offset: -3px; }
.experiment-announcement { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); }

@media (max-width: 760px) {
  .experiment-track { --slide-width: calc(100vw - 48px); gap: 16px; }
  .experiment-slide { border-radius: 14px; }
  .experiment-navigation { gap: 4px; }
  .experiment-copy h2 { font-size: 20px; }
}

@media (hover: none) {
  .experiment-slide.is-current .experiment-play { opacity: 1; }
}

@media (prefers-reduced-motion: reduce) {
  .experiment-viewer *, .experiment-viewer *::before { transition: none; }
}