:root {
  color-scheme: dark;
  --canvas: #121311;
  --surface: #20231e;
  --ink: #f2f2eb;
  --line: rgba(242, 242, 235, 0.38);
  --accent: #e16a48;
  --focus: #9ed7ec;
}

* { box-sizing: border-box; }

html, body, #experience { width: 100%; min-height: 100%; }

body {
  margin: 0;
  overflow: hidden;
  background: var(--canvas);
  color: var(--ink);
  font-family: Arial, "Microsoft YaHei", sans-serif;
}

button { font: inherit; }

button:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 3px;
}

#experience { position: fixed; inset: 0; }

#scene {
  display: block;
  width: 100%;
  height: 100%;
  cursor: grab;
  touch-action: none;
}

#scene:active { cursor: grabbing; }

.toolbar {
  position: fixed;
  z-index: 2;
  top: clamp(14px, 3vw, 34px);
  left: 50%;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 7px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(18, 19, 17, 0.78);
  transform: translateX(-50%);
  backdrop-filter: blur(10px);
}

.tool-button, .viewer-button {
  display: grid;
  width: 40px;
  height: 40px;
  place-items: center;
  padding: 0;
  border: 1px solid transparent;
  border-radius: 50%;
  background: transparent;
  color: var(--ink);
  cursor: pointer;
  font-size: 22px;
  line-height: 1;
}

.tool-button:hover, .tool-button.is-active, .viewer-button:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.toolbar-divider { width: 1px; height: 22px; background: var(--line); }

.viewer {
  position: fixed;
  z-index: 10;
  inset: 0;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  grid-template-rows: minmax(0, 1fr);
  align-items: center;
  gap: clamp(10px, 2vw, 28px);
  padding: clamp(14px, 3vw, 42px);
  background: rgba(10, 11, 10, 0.96);
}

.viewer[hidden] { display: none; }

.viewer-stage {
  display: grid;
  width: 100%;
  height: 100%;
  min-width: 0;
  min-height: 0;
  place-items: center;
  overflow: hidden;
}

.viewer-stage.zoom-mode { touch-action: none; }

.viewer-stage img, .viewer-stage video {
  display: block;
  width: auto;
  height: auto;
  max-width: min(100%, calc(100vw - 180px));
  max-height: calc(100dvh - 96px);
  object-fit: contain;
}

.viewer-stage .zoomable-media {
  transform: translate(var(--pan-x, 0px), var(--pan-y, 0px)) scale(var(--zoom, 1));
  transform-origin: center;
  transition: transform 140ms ease;
}

.viewer-stage img.zoomable-media { cursor: grab; }
.viewer-stage .zoomable-media.is-dragging { cursor: grabbing; transition: none; }

.viewer-close { position: fixed; top: clamp(14px, 3vw, 42px); right: clamp(14px, 3vw, 42px); z-index: 1; font-size: 30px; }
.viewer-nav { z-index: 1; background: rgba(32, 35, 30, 0.78); border-color: var(--line); }
.zoom-tools { position: fixed; z-index: 1; bottom: clamp(14px, 3vw, 42px); left: 50%; display: flex; gap: 8px; transform: translateX(-50%); }
.zoom-tools .viewer-button { background: rgba(32, 35, 30, 0.78); border-color: var(--line); }

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 640px) {
  .toolbar { top: 12px; gap: 4px; padding: 5px; }
  .tool-button { width: 36px; height: 36px; font-size: 20px; }
  .viewer { grid-template-columns: 1fr; padding: 12px; }
  .viewer-nav { position: fixed; bottom: 18px; }
  .viewer-previous { left: 18px; }
  .viewer-next { right: 18px; }
  .zoom-tools { bottom: 18px; }
  .viewer-close { top: 12px; right: 12px; }
  .viewer-stage img, .viewer-stage video { max-width: calc(100vw - 24px); max-height: calc(100dvh - 132px); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}