:root{color-scheme:dark;--bg:#07111f;--card:#0d1b2d;--text:#f5f8ff;--muted:#abb9cd;--accent:#62d7ff;--line:#26374d}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;background:radial-gradient(ellipse at 85% 0,#182746 0,transparent 40%),var(--bg);color:var(--text);font:16px/1.7 Inter,"Segoe UI",Arial,sans-serif}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible,summary:focus-visible{outline:3px solid var(--accent);outline-offset:4px}h1,h2,h3{line-height:1.2;letter-spacing:-.025em}h1{font-size:clamp(2rem,4.6vw,3.65rem);margin:20px 0;max-width:880px}h2{font-size:clamp(1.45rem,2.5vw,2rem);margin-top:0}h3{font-size:1.13rem}p{margin:12px 0 22px}main,.header-inner,.site-footer{width:min(1120px,calc(100% - 40px));margin:auto}.site-header{border-bottom:1px solid var(--line);background:#07111fe8}.header-inner{display:flex;gap:24px;align-items:center;min-height:84px;flex-wrap:wrap;padding:14px 0}.brand{color:var(--text);font-weight:800;letter-spacing:-.02em;font-size:1.2rem}.header-inner nav{display:flex;gap:20px;flex:1;justify-content:center;flex-wrap:wrap}.header-inner nav a{color:var(--muted);padding:8px 0}.languages{position:relative}.languages summary{cursor:pointer;border:1px solid var(--line);border-radius:12px;padding:10px 16px;list-style:none;min-height:44px}.languages>div{position:absolute;right:0;top:calc(100% + 8px);min-width:200px;z-index:5;background:var(--card);border:1px solid var(--line);border-radius:14px;box-shadow:0 15px 40px #0008;padding:8px}.languages a{display:block;padding:9px 13px;color:var(--text);border-radius:8px}.languages .current{background:#163850;color:var(--accent)}.breadcrumbs{padding:25px 0 0;color:var(--muted);font-size:.85rem}.hero{display:grid;grid-template-columns:minmax(0,1fr) 150px;gap:40px;align-items:center;padding:38px 0 52px}.eyebrow{color:var(--accent);font-size:.72rem;letter-spacing:.12em;font-weight:700}.lead{font-size:1.12rem;color:#c2cee0;max-width:790px}.tag{display:inline-block;color:var(--accent);font-size:.8rem;line-height:1.45;background:#163347;border:1px solid #24516a;padding:7px 10px;border-radius:9px}.sound-mark{display:flex;align-items:center;justify-content:center;gap:5px;height:140px;padding:15px;border:1px solid var(--line);border-radius:30px;background:linear-gradient(145deg,#17273e,#0d192b);transform:rotate(-7deg)}.sound-mark i{height:var(--h);width:6px;border-radius:5px;background:linear-gradient(#62d7ff,#7d6cff)}.cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.cards.two{grid-template-columns:repeat(2,minmax(0,1fr))}.guide-card{padding:27px;border:1px solid var(--line);border-radius:23px;background:var(--card);display:flex;flex-direction:column}.guide-card h3{font-size:1.4rem;margin:23px 0 10px}.guide-card h3 a{color:var(--text)}.guide-card p{color:var(--muted)}.text-link{margin-top:auto;font-weight:650;padding:8px 0}.topic-panel,.start{padding:30px;border:1px solid #2f5271;border-radius:23px;background:linear-gradient(120deg,#102b41,#152139);margin:35px 0}.topic-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px;margin:20px 0 30px}.topic-links a{padding:12px 14px;background:#08162588;border:1px solid var(--line);border-radius:12px}.topic-panel p{max-width:850px;color:#c2cee0}.article-layout{display:grid;grid-template-columns:250px minmax(0,1fr);gap:46px;align-items:start}.toc{position:sticky;top:25px;border:1px solid var(--line);background:var(--card);border-radius:18px;padding:22px}.toc h2{font-size:1rem;color:var(--muted);margin-bottom:15px}.toc>a{display:block;padding:8px 0;line-height:1.45;font-size:.9rem}.article-body{min-width:0}.article-body section{margin:42px 0;scroll-margin-top:30px}.callout{border-left:3px solid var(--accent);padding:20px 24px;background:#10293d;border-radius:0 16px 16px 0}.callout strong{font-size:1.12rem}.callout p{margin-bottom:0;color:#c2cee0}.article-body p,.steps p{color:#c2cee0}.steps{padding-left:28px}.steps li{padding-left:10px;margin:24px 0}.steps li::marker{font-weight:800;color:var(--accent)}.steps h3{margin:0 0 8px}.button{display:inline-flex;align-items:center;justify-content:center;background:linear-gradient(115deg,#62d7ff,#8bb5ff);color:#061523;border:0;border-radius:12px;padding:13px 22px;font-weight:750;min-height:48px;line-height:1.3}.button:hover{filter:brightness(1.08);text-decoration:none}.toc .button{padding:12px;margin-top:15px;font-size:.85rem}.calculator{padding:24px;border:1px solid var(--line);background:var(--card);border-radius:20px}.calc-fields{display:grid;grid-template-columns:1fr 1fr;gap:20px}label{display:block;color:var(--muted);font-weight:600}input,select{width:100%;display:block;margin-top:8px;padding:12px 14px;border:1px solid #405676;border-radius:10px;background:#07111f;color:var(--text);font:inherit;min-height:48px}output{display:block;font-size:2rem;font-weight:800;color:var(--accent);line-height:1.4;margin-top:8px}.article-body .muted,.muted{color:var(--muted);font-size:.9rem}.table-wrap{overflow-x:auto}table{width:100%;border-collapse:collapse;font-size:.88rem;min-width:280px}caption{text-align:left;font-weight:700;color:var(--text);padding:14px 0}th,td{text-align:left;padding:12px 10px;border-bottom:1px solid var(--line)}th{color:var(--accent)}.faq{padding:17px 20px;border:1px solid var(--line);background:var(--card);border-radius:12px;margin:10px 0}.faq summary{cursor:pointer;font-weight:650;min-height:26px}.faq p{margin:15px 0 0}.related{margin:60px 0 45px}.site-footer{border-top:1px solid var(--line);padding:30px 0 45px;display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap;color:var(--muted);margin-top:60px}.site-footer p{margin:6px 0}.site-footer nav{display:flex;align-items:start;gap:18px;flex-wrap:wrap}.site-footer a{padding:10px 0;font-size:.9rem}.skip{position:absolute;left:12px;top:-100px;z-index:10;background:var(--accent);color:#061523;padding:12px}.skip:focus{top:10px}@media(max-width:850px){.cards{grid-template-columns:1fr}.article-layout{grid-template-columns:1fr;gap:25px}.toc{position:static}.toc>a{display:inline-block;margin-right:18px}.toc .button{display:flex}.hero{grid-template-columns:1fr 100px;gap:20px}.sound-mark{height:110px;padding:12px;gap:3px}.sound-mark i{width:4px}.header-inner{gap:14px}.header-inner nav{order:3;flex-basis:100%;justify-content:flex-start;gap:24px}.languages{margin-left:auto}.article-body section{margin:30px 0}}@media(max-width:540px){main,.header-inner,.site-footer{width:calc(100% - 32px)}.hero{display:block;padding:26px 0 35px}.sound-mark{display:none}.cards.two,.topic-links,.calc-fields{grid-template-columns:1fr}.guide-card,.topic-panel,.start{padding:23px}.calculator{padding:18px}.brand{font-size:1.05rem}.languages summary{padding:9px;font-size:.85rem}.header-inner nav{font-size:.88rem;gap:18px}.lead{font-size:1rem}.site-footer{margin-top:40px}.site-footer nav{gap:16px}.callout{padding:18px}.toc{padding:18px}output{font-size:1.6rem}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}@media print{body{background:white;color:#111}.site-header,.toc,.sound-mark,.skip{display:none}.article-layout,.cards{display:block}.guide-card,.callout,.calculator,.faq,.start{background:white;border-color:#bbb;break-inside:avoid}.article-body p,.muted,.lead,.tag,.guide-card p{color:#333}a{color:#111;text-decoration:underline}}