@import url('https://fonts.googleapis.com/css2?family=DM+Mono:wght@400;500&family=Manrope:wght@400;500;600;700;800&display=swap');
:root{--bg:#07111f;--panel:#0d1a2d;--line:#203752;--text:#eef6ff;--muted:#8da4ba;--cyan:#56d9e8;--violet:#a994ff;--amber:#f3bd69;--green:#75e0a1;--danger:#fb8d9b;--shadow:0 20px 60px #02081280}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:radial-gradient(circle at 83% 5%,#15304d 0,transparent 28rem),var(--bg);color:var(--text);font-family:Manrope,system-ui,sans-serif;min-height:100vh}.app-shell{max-width:1160px;margin:auto;padding:0 28px}.topbar{height:78px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid #ffffff0d}.brand{display:flex;align-items:center;gap:10px;color:var(--text);text-decoration:none}.brand-mark{font-size:30px;color:var(--cyan);transform:rotate(-18deg)}.brand strong,.brand small{display:block}.brand small{font:11px 'DM 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var(--line);color:var(--text);border-radius:9px;padding:11px 15px;cursor:pointer;font:600 13px Manrope}footer{display:flex;justify-content:space-between;color:#688199;font-size:11px;padding:45px 0 28px;border-top:1px solid #ffffff0d;margin-top:64px}@media(max-width:700px){.app-shell{padding:0 16px}.topbar{height:66px}.hero{padding:32px 25px;min-height:0}.signal-visual{position:absolute;right:-80px;bottom:-40px;opacity:.45;transform:scale(.7)}.hero-copy{max-width:none}.hero p{max-width:90%}.stats-grid{grid-template-columns:1fr;gap:8px}.section-heading{margin-top:40px}.topic{grid-template-columns:28px 1fr 54px}.topic-bar{display:none}.topic-percent{font-size:11px}.lesson{padding:23px 20px}.lesson h3{font-size:23px}footer{display:block;line-height:2}}

body.light{--bg:#eef3f8;--line:#d4e0ea;--text:#14283b;--muted:#5e7488;--shadow:0 20px 60px #29445a1a;background:radial-gradient(circle at 83% 5%,#d8f4f6 0,transparent 28rem),var(--bg)}body.light .topbar{border-color:#14283b18}body.light .panel{background:linear-gradient(135deg,#fff,#f5f9fc);border-color:#14283b18}body.light .stat-card,body.light .topic{background:#ffffffb8;border-color:#14283b18}body.light .question{background:#14283b08;border-color:#14283b18}body.light .answer,body.light .formula{background:#f7fafc;color:var(--text);border-color:var(--line)}body.light .icon-button,body.light .secondary-button{background:#ffffffaa;color:var(--text);border-color:var(--line)}body.light footer{border-color:#14283b18}
.audio-section{margin-top:54px;padding:28px 32px}.audio-intro{color:var(--muted);font-size:13px;margin:-6px 0 20px}.audio-note{color:var(--muted);font:11px 'DM Mono'}.audio-list{display:grid;gap:10px}.audio-item{display:grid;grid-template-columns:38px 1fr;gap:14px;padding:14px 0;border-top:1px solid #ffffff12}.audio-index{color:var(--cyan);font:12px 'DM Mono';padding-top:3px}.audio-title{font-weight:700;font-size:14px}.audio-desc{font-size:11px;color:var(--muted);margin:3px 0 10px}.audio-item audio{width:100%;height:34px}body.light .audio-item{border-color:#14283b18}@media(max-width:700px){.audio-section{padding:23px 20px}.audio-note{display:none}}