:root {
  --bg: #0e0e14;
  --panel: #181822;
  --panel-2: #1f1f2c;
  --border: #2a2a3a;
  --accent: #4ade80;
  --accent-dim: #2d6a3f;
  --body1: #60a5fa;
  --body2: #fb923c;
  --text: #e6e6f0;
  --text-dim: #8888a0;
  --danger: #f87171;
  --topbar-h: 48px;
  --tabbar-h: 56px;
  --tap: 44px;  /* 最小触控目标 */
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", sans-serif;
  font-size: 14px;
  line-height: 1.45;
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: transparent;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100dvh;
  height: 100vh;
  height: 100dvh;
  overflow: hidden;
}

h1 { margin: 0; font-size: 16px; font-weight: 600; }
h2 { margin: 8px 0 6px; font-size: 13px; font-weight: 600; color: var(--accent); }

/* 顶栏 */
.topbar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 0 14px;
  height: var(--topbar-h);
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  padding-top: env(safe-area-inset-top, 0);
}

.help { color: var(--text-dim); position: relative; }
.help summary {
  cursor: pointer;
  user-select: none;
  font-size: 12px;
  color: var(--accent);
  padding: 6px 8px;
  border-radius: 4px;
}
.help summary:hover { background: var(--panel-2); }
.help summary::-webkit-details-marker { display: none; }
.help[open] > ul {
  position: absolute;
  right: 0;
  top: 32px;
  width: min(320px, 92vw);
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 12px 16px;
  list-style: disc;
  margin: 0;
  box-shadow: 0 8px 24px rgba(0,0,0,0.6);
  font-size: 12.5px;
  z-index: 100;
}

/* 主体三栏布局（桌面） */
.layout {
  display: grid;
  grid-template-columns: 340px 1fr 280px;
  grid-template-areas: "params stage metrics";
  gap: 10px;
  padding: 10px;
  flex: 1;
  min-height: 0;
  overflow: hidden;
}

.panel, .stage {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow: hidden;
  min-height: 0;
}

.panel { grid-area: var(--area); }
.params { grid-area: params; padding: 10px; overflow-y: auto; display: flex; flex-direction: column; gap: 8px; }
.stage  { grid-area: stage;  padding: 8px;  display: flex; flex-direction: column; gap: 8px; }
.metrics{ grid-area: metrics;padding: 12px; overflow-y: auto; }

/* 控件 */
fieldset {
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 6px 10px 8px;
  margin: 0;
}
legend {
  padding: 0 6px;
  font-size: 12px;
  color: var(--accent);
  font-weight: 600;
}
.legend-body1 { color: var(--body1); }
.legend-body2 { color: var(--body2); }

.adv summary {
  font-size: 12px;
  color: var(--text-dim);
  cursor: pointer;
  padding: 4px 0;
}

label {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  font-size: 12.5px;
  margin: 4px 0;
  color: var(--text);
}

input[type="number"] {
  width: 130px;
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 6px 8px;
  font-family: ui-monospace, "SF Mono", Consolas, monospace;
  font-size: 12.5px;
  min-height: 32px;
}
input[type="number"]:focus {
  outline: none;
  border-color: var(--accent);
}

button {
  background: var(--panel-2);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 6px 10px;
  font-size: 12.5px;
  cursor: pointer;
  min-height: 32px;
  transition: background 0.15s, border-color 0.15s;
}
button:hover:not(:disabled) {
  background: var(--accent-dim);
  border-color: var(--accent);
}
button:active:not(:disabled) {
  transform: scale(0.97);
}
button:disabled { opacity: 0.4; cursor: not-allowed; }

button.primary {
  background: var(--accent-dim);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
  padding: 10px 14px;
  font-size: 14px;
  min-height: var(--tap);
}
button.primary:hover { background: var(--accent); color: #0e0e14; }

.preset-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px;
}
.quick-row {
  display: flex;
  gap: 4px;
  margin-bottom: 6px;
  flex-wrap: wrap;
}
.quick-row button {
  flex: 1;
  min-width: 50px;
  padding: 4px 4px;
  font-size: 11.5px;
}

.status {
  font-size: 12px;
  min-height: 18px;
  padding: 4px 0;
  color: var(--text-dim);
  font-family: ui-monospace, "SF Mono", Consolas, monospace;
  word-break: break-all;
}
.status.error { color: var(--danger); }
.status.ok    { color: var(--accent); }

/* Canvas */
.canvas-stack {
  position: relative;
  flex: 1;
  background: #050508;
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
  min-height: 0;
}
.canvas-stack canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

/* 播放控制 */
.playback {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  padding: 6px 8px;
  background: var(--panel-2);
  border-radius: 4px;
  flex-shrink: 0;
}
.playback button {
  min-width: var(--tap);
  min-height: var(--tap);
  font-size: 16px;
  padding: 0 12px;
}
.playback .slider {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
}
.playback .slider.grow { flex: 1; min-width: 120px; }
.playback .slider input[type="range"] {
  flex: 1;
  min-width: 60px;
  height: var(--tap);
  -webkit-appearance: none;
  appearance: none;
  background: transparent;
}
.playback .slider input[type="range"]::-webkit-slider-runnable-track {
  height: 4px; background: var(--border); border-radius: 2px;
}
.playback .slider input[type="range"]::-moz-range-track {
  height: 4px; background: var(--border); border-radius: 2px;
}
.playback .slider input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 18px; height: 18px; border-radius: 50%;
  background: var(--accent); border: none; cursor: pointer;
  margin-top: -7px;
}
.playback .slider input[type="range"]::-moz-range-thumb {
  width: 18px; height: 18px; border-radius: 50%;
  background: var(--accent); border: none; cursor: pointer;
}
.playback .slider span {
  min-width: 50px;
  text-align: right;
  font-family: ui-monospace, "SF Mono", Consolas, monospace;
  color: var(--text-dim);
  font-size: 11.5px;
}
.playback .slider .slider-label {
  min-width: 28px;
  text-align: left;
  color: var(--text);
}

/* 度量列表 */
.metric-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px 8px;
  margin: 0 0 12px;
  font-size: 12px;
}
.metric-list dt { color: var(--text-dim); }
.metric-list dd {
  margin: 0;
  font-family: ui-monospace, "SF Mono", Consolas, monospace;
  color: var(--text);
  text-align: right;
  word-break: break-all;
}

/* 底部 tabs（仅移动） */
.bottom-tabs {
  display: none;
  height: var(--tabbar-h);
  background: var(--panel);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
  padding-bottom: env(safe-area-inset-bottom, 0);
}
.bottom-tabs .tab-btn {
  flex: 1;
  border: none;
  border-radius: 0;
  background: transparent;
  color: var(--text-dim);
  font-size: 13px;
  font-weight: 500;
  height: 100%;
  border-top: 2px solid transparent;
}
.bottom-tabs .tab-btn:hover { background: var(--panel-2); border-color: transparent; }
.bottom-tabs .tab-btn.active {
  color: var(--accent);
  border-top-color: var(--accent);
}

/* ============ 平板（双栏） ============ */
@media (max-width: 1099px) and (min-width: 768px) {
  .layout {
    grid-template-columns: 300px 1fr;
    grid-template-areas:
      "params stage"
      "metrics metrics";
    grid-template-rows: 1fr auto;
  }
  .metrics {
    max-height: 28vh;
  }
  .metrics h2:first-child { margin-top: 0; }
  .metric-list {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ============ 手机（单栏 + bottom tabs） ============ */
@media (max-width: 767px) {
  h1 { font-size: 15px; }

  .layout {
    display: block;
    grid-template-columns: none;
    grid-template-areas: none;
    padding: 0;
    gap: 0;
    position: relative;
    flex: 1;
    overflow: hidden;
  }

  .panel, .stage {
    position: absolute;
    inset: 0;
    border-radius: 0;
    border: none;
    border-bottom: 1px solid var(--border);
    display: none;
  }
  .panel.active, .stage.active {
    display: flex;
    flex-direction: column;
  }

  .params { padding: 10px 12px 16px; overflow-y: auto; }
  .metrics { padding: 12px 14px 16px; overflow-y: auto; }
  .stage { padding: 6px 6px 6px; }

  /* 移动端控件加大 */
  input[type="number"] {
    width: 130px;
    min-height: var(--tap);
    font-size: 14px;
  }
  button {
    min-height: var(--tap);
    font-size: 13px;
  }
  label {
    font-size: 13px;
    margin: 6px 0;
  }
  .preset-grid {
    grid-template-columns: 1fr 1fr;
    gap: 6px;
  }
  .quick-row button { min-height: var(--tap); font-size: 12.5px; }

  .metric-list {
    grid-template-columns: 1fr 1fr;
    gap: 6px 12px;
    font-size: 13.5px;
  }

  /* 播放控制紧凑 */
  .playback {
    padding: 6px 4px;
    gap: 6px;
  }
  .playback button {
    min-width: var(--tap);
    padding: 0 10px;
    font-size: 17px;
  }
  .playback .slider {
    font-size: 11.5px;
  }
  .playback .slider.grow {
    flex-basis: 100%;
    min-width: 0;
  }
  .playback .slider:not(.grow) {
    min-width: 0;
  }

  /* 显示底部 tabs */
  .bottom-tabs {
    display: flex;
  }
}

/* 极窄屏（< 360px） */
@media (max-width: 359px) {
  .preset-grid { grid-template-columns: 1fr; }
  input[type="number"] { width: 110px; }
  .playback .slider:not(.grow) { display: none; }  /* 极窄屏隐藏速度滑块 */
}