:root{--bg:#000;--bg-soft:#0a0a0a;--panel:#0f0f0f;--panel-hi:#171717;--panel-line:#262626;--text:#f5f5f5;--muted:#a3a3a3;--gold:#fff;--radar:#4ade80;--danger:#ef4444;--blue:#38bdf8;--font-display:"Space Grotesk", sans-serif;--font-body:"Inter", sans-serif;--font-mono:"JetBrains Mono", monospace}*{box-sizing:border-box}html{scroll-behavior:smooth}body{color:var(--text);font-family:var(--font-body);-webkit-font-smoothing:antialiased;background:#000;margin:0;line-height:1.55}a{color:inherit}::selection{color:#000;background:#fff}:focus-visible{outline-offset:3px;outline:2px solid #fff}.wrap{z-index:10;max-width:860px;margin:0 auto;padding:0 24px;position:relative}.hero{padding:40px 0 28px;position:relative}.eyebrow{font-family:var(--font-mono);color:var(--radar);letter-spacing:.08em;text-transform:uppercase;background:#4ade8014;border:1px solid #4ade8040;border-radius:100px;align-items:center;gap:8px;margin-bottom:20px;padding:5px 12px;font-size:12px;display:inline-flex}.eyebrow .dot{background:var(--radar);border-radius:50%;width:6px;height:6px}h1.hero-title{font-family:var(--font-display);letter-spacing:-.02em;color:#fff;margin:0 0 16px;font-size:clamp(30px,5vw,48px);font-weight:700;line-height:1.1}h1.hero-title .accent{color:#fff;text-underline-offset:6px;text-decoration:underline 3px #a855f780}.hero-sub{color:var(--muted);max-width:680px;margin:0 0 8px;font-size:17px;line-height:1.625}.hero-sub b{color:#fff;font-weight:600}section{border-top:1px solid var(--panel-line);padding:56px 0}section:first-of-type{border-top:none}.num{font-family:var(--font-mono);color:var(--radar);letter-spacing:.08em;text-transform:uppercase;font-size:12px;font-weight:600}h2{font-family:var(--font-display);letter-spacing:-.01em;color:#fff;margin:8px 0 12px;font-size:clamp(22px,3.2vw,30px);font-weight:700}.lede{color:var(--muted);max-width:640px;margin-bottom:28px;font-size:15.5px;line-height:1.625}.concept-card{background:var(--panel);border:1px solid var(--panel-line);border-radius:14px;margin-bottom:20px;padding:24px;box-shadow:0 8px 24px #00000080}.concept-card h3{font-family:var(--font-display);color:#fff;margin:0 0 10px;font-size:18px;font-weight:700}.schema-grid{grid-template-columns:1fr 1fr;gap:16px;margin-top:16px;display:grid}@media (width<=640px){.schema-grid{grid-template-columns:1fr}}.schema-box{font-size:13px;line-height:1.6;font-family:var(--font-mono);border-radius:12px;padding:16px}.schema-box.sql{color:#7dd3fc;background:#38bdf80f;border:1px solid #38bdf840}.schema-box.nosql{color:#c4b5fd;background:#a855f70f;border:1px solid #a855f740}.schema-box .tag{letter-spacing:.06em;text-transform:uppercase;margin-bottom:8px;font-size:11px;font-weight:700;display:block}.schema-box.sql .tag{color:var(--blue)}.schema-box.nosql .tag{color:#a855f7}.quiz-scenario{background:var(--bg-soft);border:1px solid var(--panel-line);border-radius:12px;margin-bottom:12px;padding:16px;transition:all .3s}.quiz-scenario .q-text{color:#e5e5e5;margin-bottom:12px;font-size:14px;line-height:1.5}.quiz-btns{gap:10px;display:flex}.quiz-btn{cursor:pointer;font-family:var(--font-mono);border:1px solid var(--panel-line);background:var(--panel);color:var(--muted);text-align:center;border-radius:8px;flex:1;padding:10px;font-size:12px;font-weight:600;transition:all .2s}.quiz-btn:hover{color:#fff;border-color:#525252}.quiz-btn.correct{border-color:var(--radar);color:var(--radar);pointer-events:none;background:#4ade801f}.quiz-btn.wrong{border-color:var(--danger);color:var(--danger);pointer-events:none;background:#ef44441a}.quiz-btn.dimmed{opacity:.4;pointer-events:none}.quiz-explain{background:var(--panel);border:1px solid var(--panel-line);color:var(--muted);font-size:12px;line-height:1.6;font-family:var(--font-body);border-radius:8px;margin-top:10px;padding:10px 12px;display:none}.quiz-explain.show{display:block}.compare-table{border-collapse:collapse;width:100%;font-size:13px;font-family:var(--font-mono)}.compare-table th{text-align:left;text-transform:uppercase;letter-spacing:.06em;border-bottom:2px solid var(--panel-line);color:var(--muted);padding:12px 14px;font-size:11px;font-weight:700}.compare-table th.sql-col{color:var(--blue)}.compare-table th.nosql-col{color:#a855f7}.compare-table td{border-bottom:1px solid var(--panel-line);color:#d4d4d4;vertical-align:top;padding:12px 14px}.compare-table tr:last-child td{border-bottom:none}.compare-table td:first-child{color:var(--muted);font-weight:600}.rubric-box{background:var(--panel);border:1px solid var(--panel-line);font-family:var(--font-mono);border-radius:14px;padding:24px;font-size:12.5px}.rubric-item{border:1px solid var(--panel-line);background:#0a0a0a;border-radius:8px;margin-bottom:8px;padding:10px 14px}