:root{color-scheme:dark;--bg:#060806;--panel:#0c0f0c;--panel2:#10130f;--line:#302a18;--gold:#d9b34b;--gold2:#80651f;--text:#f1ede2;--muted:#bdb7a8;--ok:#65d6a2;--bad:#ff8a8f}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:radial-gradient(circle at 20% 0,#17180f 0,transparent 28%),var(--bg);color:var(--text);font-family:Tahoma,Arial,sans-serif;line-height:1.95}.wrap{max-width:1120px;margin:auto;padding:28px 18px 96px}.crumb{font-size:13px;color:#979184;margin-bottom:12px}.crumb a,a{color:var(--gold)}
.lesson-shell{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:22px;align-items:start}.lesson-main{min-width:0}.side{position:sticky;top:18px}.hero,.card,.quiz,.tool,.sidebox{background:rgba(12,15,12,.96);border:1px solid var(--line);border-radius:20px;padding:26px;margin:18px 0}.hero{background:linear-gradient(135deg,#11140f,#080a08)}.hero-kicker{color:var(--gold);font-weight:800;letter-spacing:.08em;font-size:12px}.hero h1{font-size:38px;line-height:1.45;margin:8px 0 10px;max-width:760px}.hero p{max-width:800px;color:#cbc5b8;margin:0}.meta{display:flex;gap:8px;flex-wrap:wrap;margin-top:14px}.pill{border:1px solid #57471e;border-radius:30px;padding:4px 11px;color:#cfc7b5;font-size:12px}
.card h2,.quiz h2,.tool h2{margin-top:0}.toc,.concept-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}.toc span,.concept{background:var(--panel2);border:1px solid #29291f;border-radius:12px;padding:12px}.term{padding:16px;border-right:3px solid var(--gold);background:var(--panel2);border-radius:10px;margin:12px 0}.term b:first-child{font-size:17px}.term .use{display:block;color:#c8c2b4;margin-top:5px}.example{padding:15px;background:#15170f;border-radius:12px;margin-top:12px}.warning{border-right:3px solid #9d7830;padding:12px 15px;background:#17130b;border-radius:8px;margin:12px 0}.ok{border-right-color:#2f8f68;background:#0d1713}.flow{display:flex;gap:8px;flex-wrap:wrap;align-items:center}.flow span{background:#11150f;border:1px solid #3b3420;padding:8px 11px;border-radius:10px}.compare{width:100%;border-collapse:collapse;min-width:560px}.table-wrap{overflow-x:auto}.compare th,.compare td{padding:12px;border-bottom:1px solid #2b2a21;text-align:right}.compare th{color:var(--gold)}
.tool{border-color:var(--gold2);background:#151208}.tool small{color:#e1bd55}.cta{display:inline-block;text-decoration:none;background:var(--gold);color:#171108;font-weight:bold;padding:9px 16px;border-radius:10px}.tool-note{font-size:13px;color:#c1b9a8}.quiz-option{display:block;width:100%;text-align:right;padding:11px 12px;background:#11140f;color:var(--text);margin:7px 0;border:1px solid #29291f;border-radius:9px;cursor:pointer}.quiz-option:hover{border-color:var(--gold2)}.quiz-option.correct{border-color:#2f8f68;background:#0e1b15}.quiz-option.wrong{border-color:#8f3d43;background:#1c1012}.quiz-feedback{min-height:28px;color:#cfc7b5;margin-top:8px}
.nav{display:flex;justify-content:space-between;gap:12px;margin-top:25px}.nav a{text-decoration:none}.sidebox{padding:16px;margin:0 0 12px}.sidebox h3{margin:0 0 10px}.sidebox a{display:block;text-decoration:none;padding:6px 0;color:#c3bdaf}.progress{height:8px;background:#24241d;border-radius:20px;overflow:hidden;margin:9px 0}.progress i{display:block;height:100%;background:var(--gold);width:0}.lesson-done{width:100%;padding:12px;border-radius:11px;border:1px solid var(--gold2);background:#17130b;color:#e8c45a;font-weight:bold;cursor:pointer}.lesson-done.is-done{background:#0f2119;border-color:#2f8f68;color:#76e0b2}.source-note{font-size:12px;color:#817c70}
.sim-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.sim-card{background:#10130f;border:1px solid #302a18;border-radius:14px;padding:15px}.sim-card button{border:1px solid var(--gold2);background:#17130b;color:#e8c45a;border-radius:9px;padding:8px 12px;cursor:pointer}.sim-output{margin-top:10px;padding:11px;border-radius:9px;background:#090c09;color:#c9c4b7;min-height:64px}.risk-flag{color:#ffb0b4}.safe-note{color:#83ddb7}.small{font-size:12px;color:#918b7f}
@media(max-width:850px){.lesson-shell{grid-template-columns:1fr}.side{position:static;order:-1}.concept-grid,.toc,.sim-grid{grid-template-columns:1fr}.hero h1{font-size:32px}}
@media(max-width:560px){.wrap{padding:18px 12px 80px}.hero,.card,.quiz,.tool{padding:18px;border-radius:16px}.hero h1{font-size:27px}.nav{flex-direction:column}.compare{min-width:520px}}