:root {
  --bg-top: #f7f3ec;
  --bg-bottom: #eef3fa;
  --panel: rgba(255, 255, 255, 0.96);
  --ink: #161616;
  --muted: #5e5e5e;
  --line: rgba(25, 37, 52, 0.14);
  --prism: #7193d8;
  --prism-deep: #384e8e;
  --pyramid: #df64a5;
  --pyramid-deep: #9a2f68;
  --accent: #f4b841;
  --shadow: 0 18px 50px rgba(27, 39, 61, 0.14);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Trebuchet MS", "Gill Sans", sans-serif;
  color: var(--ink);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.7), rgba(255, 255, 255, 0.2)),
    linear-gradient(160deg, var(--bg-top), var(--bg-bottom));
}

button,
input {
  font: inherit;
}

.page-shell {
  max-width: 1500px;
  margin: 0 auto;
  padding: 24px;
}

.hero {
  display: block;
  margin-bottom: 20px;
  padding: 22px 28px 20px;
  border: 3px solid rgba(18, 18, 18, 0.18);
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: var(--shadow);
  text-align: center;
}

.eyebrow,
.panel-label {
  margin: 0 0 10px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 0.78rem;
  font-weight: 700;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: Georgia, "Times New Roman", serif;
}

h1 {
  font-size: clamp(2.9rem, 5vw, 5rem);
  line-height: 0.92;
  letter-spacing: -0.03em;
}

.hero-copy {
  max-width: 760px;
  margin: 14px auto 0;
  font-size: 1.03rem;
  line-height: 1.5;
}

.layout {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(320px, 0.9fr);
  gap: 20px;
}

.viewer-panel,
.shape-picker,
.fact-card,
.teaching-card,
.hint-card {
  border: 3px solid rgba(18, 18, 18, 0.12);
  border-radius: 26px;
  background: var(--panel);
  box-shadow: var(--shadow);
}

.viewer-panel {
  padding: 22px;
}

.panel-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid rgba(22, 22, 22, 0.08);
}

.ghost-button,
.quick-actions button,
.picker-grid button {
  border: 0;
  border-radius: 18px;
  cursor: pointer;
  transition:
    transform 0.18s ease,
    box-shadow 0.18s ease,
    background 0.18s ease;
}

.ghost-button {
  padding: 12px 18px;
  color: var(--ink);
  background: rgba(22, 22, 22, 0.06);
  border: 1px solid rgba(22, 22, 22, 0.08);
}

.ghost-button:hover,
.quick-actions button:hover,
.picker-grid button:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 18px rgba(27, 39, 61, 0.12);
}

.stage-wrap {
  position: relative;
  overflow: hidden;
  min-height: 560px;
  border-radius: 24px;
  border: 2px solid rgba(22, 22, 22, 0.08);
  background:
    radial-gradient(circle at 40% 24%, rgba(255, 255, 255, 0.98), rgba(247, 244, 239, 0.95) 58%, rgba(239, 235, 228, 0.92));
}

.stage-wrap::before {
  content: "";
  position: absolute;
  inset: 18px;
  border-radius: 20px;
  border: 2px dashed rgba(22, 22, 22, 0.08);
  pointer-events: none;
}

.shape-stage {
  width: 100%;
  height: 100%;
  min-height: 560px;
  touch-action: none;
  cursor: grab;
}

.shape-stage.dragging {
  cursor: grabbing;
}

.controls {
  display: grid;
  gap: 16px;
  margin-top: 18px;
}

.slider-block {
  padding: 18px;
  border-radius: 22px;
  background: #fbfaf7;
  border: 1px solid rgba(22, 22, 22, 0.08);
}

.slider-block label {
  display: block;
  margin-bottom: 10px;
  font-weight: 800;
}

.slider-block input {
  width: 100%;
}

.slider-scale {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin-top: 10px;
  color: var(--muted);
  font-size: 0.93rem;
}

.quick-actions {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.quick-actions button {
  padding: 15px 12px;
  font-weight: 800;
  color: var(--ink);
  background: linear-gradient(180deg, #ffffff, #f1efe9);
}

.teaching-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.teaching-strip span {
  padding: 12px 14px;
  border-radius: 18px;
  background: #fbfaf7;
  border: 1px solid rgba(22, 22, 22, 0.1);
  font-size: 0.95rem;
  line-height: 1.45;
}

.teaching-strip strong {
  display: block;
  margin-bottom: 2px;
  font-size: 1rem;
}

.info-panel {
  display: grid;
  gap: 16px;
}

.shape-picker,
.fact-card,
.teaching-card,
.hint-card {
  padding: 18px;
}

.picker-group + .picker-group {
  margin-top: 20px;
  padding-top: 18px;
  border-top: 2px solid rgba(22, 22, 22, 0.08);
}

.picker-group h3,
.fact-card h3,
.teaching-card h3,
.hint-card h3 {
  margin-bottom: 12px;
  font-size: 1.7rem;
}

.group-note {
  margin: -4px 0 12px;
  font-size: 0.96rem;
  color: var(--muted);
  line-height: 1.4;
}

.prism-group h3,
.prism-group .group-note {
  color: var(--prism-deep);
}

.pyramid-group h3,
.pyramid-group .group-note {
  color: var(--pyramid-deep);
}

.picker-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.picker-grid button {
  padding: 14px 12px;
  text-align: left;
  color: var(--ink);
  background: #fffdf8;
  border: 2px solid rgba(22, 22, 22, 0.08);
  min-height: 64px;
  font-weight: 700;
}

.picker-grid button.active {
  border-color: rgba(22, 22, 22, 0.22);
  background: linear-gradient(180deg, #ffffff, rgba(244, 184, 65, 0.16));
}

.fact-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.fact-grid div {
  padding: 14px;
  border-radius: 18px;
  background: #fbfaf7;
  border: 1px solid rgba(22, 22, 22, 0.08);
}

.fact-label {
  display: block;
  margin-bottom: 4px;
  color: var(--muted);
  font-size: 0.88rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

#prismButtons button.active {
  background: linear-gradient(180deg, #ffffff, rgba(113, 147, 216, 0.2));
}

#pyramidButtons button.active {
  background: linear-gradient(180deg, #ffffff, rgba(223, 100, 165, 0.2));
}

.fact-grid strong {
  font-size: 1.4rem;
}

.teaching-card ul {
  margin: 0;
  padding-left: 20px;
  line-height: 1.5;
}

.hint-card p {
  margin: 0;
  line-height: 1.65;
}

@media (max-width: 1080px) {
  .layout {
    grid-template-columns: 1fr;
  }

  .hero {
    text-align: left;
  }
}

@media (max-width: 720px) {
  .page-shell {
    padding: 14px;
  }

  .hero,
  .viewer-panel,
  .shape-picker,
  .fact-card,
  .teaching-card,
  .hint-card {
    border-radius: 22px;
  }

  .panel-head,
  .hero-badge,
  .slider-scale,
  .quick-actions,
  .teaching-strip,
  .picker-grid,
  .fact-grid {
    grid-template-columns: 1fr;
  }

  .panel-head,
  .slider-scale {
    display: grid;
  }

  .stage-wrap,
  .shape-stage {
    min-height: 420px;
  }
}