:root {
  --ink: #eaf6ff;
  --muted: #8aa4b8;
  --cyan: #52e6ff;
  --pink: #ff5cc8;
  --bg: #03050b;
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
  overscroll-behavior: none;
}

#app {
  position: fixed;
  inset: 0;
  overflow: hidden;
  background: radial-gradient(circle at 50% 45%, #0a1730 0%, #03050b 70%);
}

#video {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

#stage {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
  touch-action: none;
  cursor: grab;
}

#stage.dragging { cursor: grabbing; }

#topbar {
  position: absolute;
  top: calc(12px + var(--safe-top));
  left: 16px;
  right: 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  pointer-events: none;
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.brand { display: flex; align-items: center; gap: 8px; }

.brand .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 12px var(--cyan);
}

.tag {
  padding: 4px 7px;
  border: 1px solid rgba(82, 230, 255, 0.28);
  border-radius: 4px;
  color: rgba(234, 246, 255, 0.62);
  font-size: 10px;
}

#hud {
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: calc(74px + var(--safe-bottom));
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 10px;
  pointer-events: none;
}

.chips { display: flex; flex-wrap: wrap; gap: 6px; }

.chip {
  padding: 5px 8px;
  border-radius: 999px;
  border: 1px solid rgba(138, 164, 184, 0.22);
  background: rgba(4, 10, 20, 0.62);
  color: var(--muted);
  font-size: 11px;
  line-height: 1;
  backdrop-filter: blur(8px);
}

.chip.ok { color: var(--cyan); border-color: rgba(82, 230, 255, 0.4); }
.chip.warn { color: #ffd27a; border-color: rgba(255, 210, 122, 0.4); }
.chip.bad { color: #ff7b9c; border-color: rgba(255, 123, 156, 0.45); }

.fps {
  color: rgba(138, 164, 184, 0.55);
  font-variant-numeric: tabular-nums;
  font-size: 10px;
  white-space: nowrap;
}

#actions {
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: calc(16px + var(--safe-bottom));
  display: flex;
  gap: 8px;
}

.btn {
  appearance: none;
  border: 1px solid rgba(138, 164, 184, 0.26);
  border-radius: 10px;
  background: rgba(5, 12, 24, 0.72);
  color: var(--ink);
  padding: 10px 14px;
  font: inherit;
  font-size: 13px;
  line-height: 1;
  backdrop-filter: blur(10px);
  cursor: pointer;
  transition: transform 0.12s ease, border-color 0.12s ease, background 0.12s ease;
}

.btn:active { transform: scale(0.97); }
.btn:disabled { opacity: 0.45; cursor: default; }

.btn.primary {
  background: linear-gradient(135deg, rgba(82, 230, 255, 0.95), rgba(90, 140, 255, 0.95));
  border-color: transparent;
  color: #021018;
  font-weight: 650;
}

.btn.ghost { margin-left: auto; color: var(--muted); }
.btn.big { padding: 14px 22px; font-size: 15px; border-radius: 12px; }

.overlay {
  position: absolute;
  inset: 0;
  z-index: 5;
  display: grid;
  place-items: center;
  padding: 22px;
  background:
    radial-gradient(circle at 50% 40%, rgba(20, 48, 90, 0.5), rgba(2, 4, 9, 0.92) 68%),
    rgba(2, 4, 9, 0.72);
  backdrop-filter: blur(6px);
  transition: opacity 0.35s ease, visibility 0.35s ease;
}

.overlay.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.panel {
  width: min(440px, 100%);
  padding: 26px 24px 22px;
  border: 1px solid rgba(82, 230, 255, 0.2);
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(10, 22, 40, 0.92), rgba(4, 8, 16, 0.94));
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.55), 0 0 40px rgba(82, 230, 255, 0.07);
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--cyan);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
}

h1, h2 {
  margin: 0 0 14px;
  font-weight: 650;
  letter-spacing: -0.02em;
  line-height: 1.16;
}

h1 { font-size: clamp(30px, 8vw, 42px); }
h2 { font-size: 24px; }

.lede {
  margin: 0 0 20px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.7;
}

.hint {
  margin: 12px 0 0;
  color: rgba(138, 164, 184, 0.7);
  font-size: 11px;
  line-height: 1.6;
}

.help-list {
  margin: 0 0 22px;
  padding-left: 18px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.8;
}

.help-list b { color: var(--ink); font-weight: 600; }

a {
  color: var(--cyan);
  text-underline-offset: 2px;
}

code {
  padding: 1px 5px;
  border-radius: 4px;
  background: rgba(82, 230, 255, 0.1);
  color: var(--cyan);
  font-size: 0.92em;
}