:root {
  --bg: #0f1117;
  --bg-card: #161b22;
  --bg-elevated: #1c2128;
  --border: #30363d;
  --text: #e6edf3;
  --text-muted: #8b949e;
  --accent-blue: #58a6ff;
  --accent-green: #3fb950;
  --accent-purple: #bc8cff;
  --accent-orange: #d29922;
  --accent-cyan: #39c5cf;
  --python: #3776AB;
  --go: #00ADD8;
  --ts: #3178C6;
  --radius: 12px;
  --shadow: 0 4px 24px rgba(0,0,0,.3);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 24px; }

a { color: var(--accent-blue); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Hero */
.hero {
  padding: 100px 0 80px;
  text-align: center;
  background: radial-gradient(ellipse at top, rgba(88,166,255,.08) 0%, transparent 60%);
}
.hero-badge {
  display: inline-block;
  padding: 4px 14px;
  border: 1px solid var(--border);
  border-radius: 20px;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 16px;
}
.logo {
  width: 72px;
  height: 72px;
  margin-bottom: 12px;
}
.hero h1 {
  font-size: clamp(36px, 6vw, 64px);
  font-weight: 800;
  letter-spacing: -2px;
  margin-bottom: 16px;
}
.gradient {
  background: linear-gradient(135deg, var(--accent-blue), var(--accent-purple), var(--accent-cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-desc {
  font-size: 18px;
  color: var(--text-muted);
  max-width: 520px;
  margin: 0 auto 32px;
}
.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 22px;
  border-radius: 8px;
  font-size: 15px;
  font-weight: 600;
  transition: all .2s;
  cursor: pointer;
  border: none;
}
.btn-primary {
  background: var(--accent-blue);
  color: #fff;
}
.btn-primary:hover { background: #79c0ff; transform: translateY(-1px); text-decoration: none; }
.cmd {
  padding: 10px 18px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 13px;
  color: var(--accent-green);
}

/* Section */
.section-title {
  font-size: 28px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
}
.section-desc {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 48px;
}
section { padding: 80px 0; }

/* Language Cards */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
}
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: transform .2s, box-shadow .2s;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow);
}
.card-header {
  padding: 28px 24px 16px;
  display: flex;
  align-items: center;
  gap: 14px;
  border-bottom: 1px solid var(--border);
}
.card-header h3 {
  font-size: 20px;
  font-weight: 700;
}
.card-python .card-header { border-left: 3px solid var(--python); }
.card-go .card-header { border-left: 3px solid var(--go); }
.card-ts .card-header { border-left: 3px solid var(--ts); }
.card-body { padding: 20px 24px 24px; }
.tech-stack {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 16px;
}
.tag {
  padding: 3px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  background: var(--bg-elevated);
  color: var(--text-muted);
  border: 1px solid var(--border);
}
.features {
  list-style: none;
}
.features li {
  padding: 4px 0;
  font-size: 14px;
  color: var(--text-muted);
  position: relative;
  padding-left: 18px;
}
.features li::before {
  content: '✓';
  position: absolute;
  left: 0;
  color: var(--accent-green);
  font-weight: 700;
  font-size: 13px;
}

/* Commands */
.commands { background: var(--bg-card); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.cmd-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 12px;
}
.cmd-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  transition: border-color .2s;
}
.cmd-item:hover { border-color: var(--accent-blue); }
.cmd-item code {
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 13px;
  color: var(--accent-cyan);
  white-space: nowrap;
}
.cmd-item span {
  font-size: 13px;
  color: var(--text-muted);
}

/* Structure / Tabs */
.tabs {
  display: flex;
  justify-content: center;
  gap: 4px;
  margin-bottom: 24px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 4px;
  width: fit-content;
  margin-left: auto;
  margin-right: auto;
}
.tab {
  padding: 8px 20px;
  border: none;
  background: none;
  color: var(--text-muted);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  border-radius: 6px;
  transition: all .2s;
}
.tab.active {
  background: var(--accent-blue);
  color: #fff;
}
.tab:hover:not(.active) { color: var(--text); }
.tab-content { display: none; }
.tab-content.active { display: block; }
.tab-content pre {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  overflow-x: auto;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-muted);
  white-space: pre;
}

/* Steps */
.steps {
  display: flex;
  align-items: flex-start;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}
.step {
  text-align: center;
  max-width: 180px;
  padding: 20px 16px;
}
.step-num {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-elevated);
  border: 2px solid var(--accent-blue);
  color: var(--accent-blue);
  font-size: 18px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 12px;
}
.step h4 { font-size: 15px; margin-bottom: 6px; }
.step p { font-size: 13px; color: var(--text-muted); }
.step-arrow {
  font-size: 24px;
  color: var(--border);
  padding-top: 44px;
}

/* Footer */
footer {
  border-top: 1px solid var(--border);
  padding: 32px 0;
  text-align: center;
  color: var(--text-muted);
  font-size: 14px;
}
footer a { color: var(--text-muted); }
footer a:hover { color: var(--text); }

/* Responsive */
@media (max-width: 768px) {
  .hero { padding: 60px 0 48px; }
  section { padding: 48px 0; }
  .cards { grid-template-columns: 1fr; }
  .cmd-grid { grid-template-columns: 1fr 1fr; }
  .steps { flex-direction: column; align-items: center; }
  .step-arrow { transform: rotate(90deg); padding-top: 0; margin: 8px 0; }
  .tabs { width: 100%; }
  .tab { flex: 1; text-align: center; }
}