:root {
  --panel: rgba(15, 22, 40, 0.56);
  --text: #ecf4ff;
  --muted: #97a8c8;
  --warn: #ffd89a;
  --line-soft: rgba(200, 225, 255, 0.045);
  --shadow: 0 30px 80px rgba(0, 0, 0, 0.42);
  --blur: blur(18px);
  --radius-xl: 28px;
  --radius-lg: 22px;
  --radius-md: 18px;
}

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
  background:
    radial-gradient(circle at 18% 12%, rgba(120, 170, 255, 0.09), transparent 0 26%),
    radial-gradient(circle at 82% 14%, rgba(109, 232, 255, 0.07), transparent 0 22%),
    linear-gradient(180deg, #060a12 0%, #09101d 42%, #070c16 100%);
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang TC", "Microsoft JhengHei", sans-serif;
  color: var(--text);
  min-height: 100vh;
  background:
    radial-gradient(circle at 12% 8%, rgba(154, 195, 255, 0.06), transparent 0 22%),
    radial-gradient(circle at 86% 10%, rgba(122, 228, 255, 0.05), transparent 0 24%),
    radial-gradient(circle at 52% 78%, rgba(199, 184, 255, 0.03), transparent 0 22%);
  overflow-x: hidden;
}

.app {
  max-width: 1580px;
  margin: 0 auto;
  padding: 18px 22px 28px;
}

.card {
  position: relative;
  background:
    linear-gradient(180deg, rgba(255,255,255,0.038), rgba(255,255,255,0.016)),
    var(--panel);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
  backdrop-filter: var(--blur) saturate(115%);
  -webkit-backdrop-filter: var(--blur) saturate(115%);
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  background:
    linear-gradient(135deg, rgba(255,255,255,0.06), transparent 24%, transparent 72%, rgba(255,255,255,0.03));
  opacity: 0.6;
}

.workspace,
.visuals,
.controls,
.main-stage,
.support-card,
.group,
.stage-header,
.support-copy {
  position: relative;
  z-index: 1;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 18px;
  align-items: start;
}

.visuals {
  display: grid;
  gap: 18px;
}

.section-title {
  display: block;
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #9bdcff;
}

.main-stage,
.controls,
.support-card {
  padding: 18px;
}

.stage-header {
  display: grid;
  gap: 10px;
  margin-bottom: 16px;
}

.stage-header h1 {
  margin: 0;
  font-size: clamp(28px, 4vw, 42px);
  letter-spacing: -0.04em;
  line-height: 1.05;
}

.stage-header p,
.support-copy p,
.canvas-caption,
.mini-tip {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.75;
}

.main-canvas-shell,
.wave-readout,
.sum-canvas-wrap {
  width: 100%;
}

canvas {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 22px;
  border: 1px solid rgba(255,255,255,0.045);
  background:
    radial-gradient(circle at center, rgba(255,255,255,0.03), rgba(255,255,255,0.008) 40%, rgba(255,255,255,0.003) 68%, transparent 100%),
    linear-gradient(180deg, rgba(10,18,34,0.88), rgba(8,13,25,0.92));
  box-shadow:
    inset 0 0 100px rgba(160, 210, 255, 0.03),
    inset 0 0 34px rgba(255,255,255,0.012),
    0 24px 60px rgba(0,0,0,0.26);
}

#mainCanvas {
  aspect-ratio: 1 / 1;
}

#waveCanvas {
  aspect-ratio: 5 / 2;
}

#sumCanvas {
  aspect-ratio: 35 / 12;
}

.canvas-caption {
  padding: 10px 4px 0;
}

.support-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.support-card {
  display: grid;
  gap: 14px;
}

.support-copy h2 {
  margin: 4px 0 0;
  font-size: 20px;
  letter-spacing: -0.03em;
}

.controls {
  position: sticky;
  top: 16px;
}

.group {
  padding: 14px;
  border-radius: var(--radius-md);
  background:
    linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0.008)),
    rgba(255,255,255,0.018);
  border: 1px solid rgba(255,255,255,0.045);
  margin-bottom: 12px;
}

.compact-group {
  box-shadow: inset 0 1px 0 rgba(255,255,255,0.025);
}

.row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  align-items: center;
  margin-bottom: 10px;
}

.mt12 {
  margin-top: 12px;
}

label {
  font-size: 13px;
  color: #dce8ff;
}

.value {
  color: var(--warn);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
}

input[type="range"] {
  width: 100%;
  margin-top: 6px;
  -webkit-appearance: none;
  appearance: none;
  height: 22px;
  background: transparent;
}

input[type="range"]::-webkit-slider-runnable-track,
input[type="range"]::-moz-range-track {
  height: 4px;
  border-radius: 999px;
  background:
    linear-gradient(90deg, rgba(139,211,255,0.3), rgba(199,184,255,0.22)),
    rgba(255,255,255,0.08);
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.035);
}

input[type="range"]::-webkit-slider-thumb,
input[type="range"]::-moz-range-thumb {
  -webkit-appearance: none;
  appearance: none;
  margin-top: -7px;
  width: 18px;
  height: 18px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,0.16);
  background:
    radial-gradient(circle at 35% 35%, rgba(255,255,255,0.95), rgba(170,220,255,0.92) 48%, rgba(140,175,255,0.82));
}

button {
  width: 100%;
  border: 1px solid rgba(255,255,255,0.06);
  background:
    linear-gradient(180deg, rgba(255,255,255,0.035), rgba(255,255,255,0.012)),
    rgba(255,255,255,0.022);
  color: var(--text);
  border-radius: 14px;
  padding: 12px 14px;
  font-size: 14px;
  cursor: pointer;
  transition: transform 0.16s ease, background 0.2s ease, border-color 0.2s ease;
}

button:hover {
  transform: translateY(-1px);
  border-color: rgba(139,211,255,0.16);
}

.button-grid,
.preset-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.preset-grid button {
  font-size: 13px;
}

.mini-tip {
  margin-top: 10px;
  padding: 10px 12px;
  border-radius: 14px;
  background: rgba(255,255,255,0.018);
  border: 1px solid rgba(255,255,255,0.04);
}

.advanced-group summary {
  cursor: pointer;
  font-size: 13px;
  color: #dce8ff;
  list-style: none;
}

.advanced-group summary::-webkit-details-marker {
  display: none;
}

.advanced-group[open] summary {
  margin-bottom: 10px;
}

@media (max-width: 1100px) {
  .workspace {
    grid-template-columns: 1fr;
  }

  .controls {
    position: static;
  }
}

@media (max-width: 840px) {
  .support-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 720px) {
  .app {
    padding: 12px;
  }

  .main-stage,
  .controls,
  .support-card {
    padding: 16px;
  }

  .button-grid,
  .preset-grid {
    grid-template-columns: 1fr;
  }

  .stage-header h1 {
    font-size: 30px;
  }
}