:root {
  color-scheme: dark;
  --bg: #0b1020;
  --panel: #121a2f;
  --border: #1f2a44;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --accent-2: #a78bfa;
  --ok: #34d399;
  --warn: #fbbf24;
  font-family: "Segoe UI", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: radial-gradient(circle at top, #172554 0%, var(--bg) 45%);
  color: var(--text);
  min-height: 100vh;
}

a {
  color: var(--accent);
}

.lang-switcher {
  position: fixed;
  top: 1rem;
  right: 1rem;
  z-index: 200;
  display: flex;
  gap: 0.35rem;
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.35rem;
  backdrop-filter: blur(8px);
}

.lang-btn {
  border: 1px solid transparent;
  background: transparent;
  color: var(--muted);
  border-radius: 6px;
  padding: 0.35rem 0.55rem;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  min-width: 2.5rem;
}

.lang-btn:hover {
  color: var(--text);
  border-color: var(--border);
}

.lang-btn.active {
  color: #0f172a;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  border-color: transparent;
}

.hero {
  padding: 1.25rem clamp(1rem, 4vw, 3rem) 0.75rem;
  padding-right: clamp(5rem, 12vw, 8rem);
  max-width: 1200px;
  margin: 0 auto;
}

.hero h1 {
  margin: 0 0 0.35rem;
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
}

.hero p {
  color: var(--muted);
  max-width: 70ch;
  line-height: 1.5;
  font-size: 0.95rem;
  margin: 0;
}

.badges {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.65rem;
}

.badge {
  display: inline-block;
  padding: 0.25rem 0.65rem;
  border-radius: 999px;
  font-size: 0.8rem;
  background: #1e293b;
  border: 1px solid var(--border);
}

.badge.ok {
  border-color: var(--ok);
  color: var(--ok);
}

.badge.warn {
  border-color: var(--warn);
  color: var(--warn);
}

.layout {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 0.75rem;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 clamp(1rem, 4vw, 3rem) 1.5rem;
  align-items: start;
}

.main-column {
  min-width: 0;
}

.play-panel {
  margin-bottom: 0.75rem;
  padding: 0.85rem 1rem;
}

.play-panel > h2 {
  margin: 0 0 0.35rem;
  font-size: 1.15rem;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
  margin: 0 0 0.65rem;
}

.results-section {
  scroll-margin-top: 4rem;
  margin-bottom: 0.75rem;
}

.results-grid {
  gap: 0.65rem;
  margin-bottom: 0;
}

.results-block {
  background: #0f172a;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.65rem 0.75rem;
}

.results-block h3 {
  margin: 0 0 0.25rem;
  font-size: 0.95rem;
  font-weight: 600;
}

.portfolio-block {
  margin-top: 0.65rem;
}

.demo-desc {
  line-height: 1.5;
  font-size: 0.9rem;
  color: var(--muted);
  margin: 0.65rem 0 0.5rem;
}

.panel-hint {
  font-size: 0.8rem;
  color: var(--muted);
  margin: 0 0 0.4rem;
  line-height: 1.4;
}

@media (max-width: 860px) {
  .layout {
    grid-template-columns: 1fr;
  }

  .hero {
    padding-right: clamp(1rem, 4vw, 3rem);
    padding-top: 3.5rem;
  }
}

.sidebar {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1rem;
  height: fit-content;
}

.demo-tab {
  display: block;
  width: 100%;
  text-align: left;
  margin-bottom: 0.5rem;
  padding: 0.65rem 0.75rem;
  border-radius: 8px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text);
  cursor: pointer;
  line-height: 1.35;
}

.demo-tab.active,
.demo-tab:hover {
  border-color: var(--accent);
  background: rgba(56, 189, 248, 0.08);
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1rem 1.25rem;
  margin-bottom: 0.75rem;
}

.panel h2 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
}

button.primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #0f172a;
  border: none;
  border-radius: 8px;
  padding: 0.55rem 1.1rem;
  font-weight: 600;
  cursor: pointer;
  font-size: 1rem;
}

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

@media (max-width: 720px) {
  .grid-2 {
    grid-template-columns: 1fr;
  }
}

canvas,
#circuit-svg {
  width: 100%;
  background: #0f172a;
  border-radius: 8px;
  border: 1px solid var(--border);
}

#circuit-svg {
  min-height: 88px;
  max-height: 140px;
  display: block;
  margin-top: 0.25rem;
}

#hist-canvas {
  height: 160px;
}

#bloch-canvas {
  height: 140px;
  max-width: 100%;
}

#portfolio-canvas {
  height: 140px;
}

.metrics {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  color: var(--muted);
  margin-top: 0.4rem;
  font-size: 0.85rem;
}

.metrics strong {
  color: var(--text);
}

.integration-hooks {
  padding-left: 1.2rem;
  color: var(--muted);
  line-height: 1.7;
}

.integration-summary {
  color: var(--text);
  line-height: 1.65;
  font-size: 1.02rem;
  margin: 0;
}

.error {
  padding: 2rem;
  color: #fca5a5;
}