:root{color-scheme:dark;--bg:#0d1018;--bg2:#171a24;--panel:rgba(255,255,255,.075);--panel2:rgba(255,255,255,.035);--line:rgba(255,255,255,.15);--text:#fff8ef;--muted:#c8bfb3;--orange:#f47a00;--orange2:#ffae35;--green:#7be0ad;--shadow:0 24px 70px rgba(0,0,0,.32)}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;min-height:100vh;background:radial-gradient(circle at 16% 0%,rgba(244,122,0,.22),transparent 28%),radial-gradient(circle at 88% 6%,rgba(255,174,53,.10),transparent 24%),linear-gradient(135deg,var(--bg),var(--bg2));color:var(--text);font-family:Inter,system-ui,-apple-system,"Segoe UI",Tahoma,Arial,sans-serif;text-rendering:optimizeLegibility}
a{color:var(--orange2)}
.shell{width:min(1080px,calc(100% - 28px));margin:0 auto;padding:20px 0 56px}
.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:12px 14px;border:1px solid var(--line);border-radius:22px;background:rgba(17,20,29,.76);backdrop-filter:blur(18px);box-shadow:0 14px 42px rgba(0,0,0,.22);position:sticky;top:10px;z-index:10}
.brand{display:flex;align-items:center;gap:11px;color:var(--text);text-decoration:none;min-width:0}.logo{width:44px;height:44px;border-radius:15px;display:grid;place-items:center;background:linear-gradient(135deg,var(--orange),var(--orange2));font-weight:1000;box-shadow:0 11px 28px rgba(244,122,0,.28)}.brand-copy b{display:block;font-size:15px}.brand-copy span{display:block;color:var(--orange2);font-size:11px;font-weight:900;margin-top:2px}
.nav{display:flex;gap:7px;flex-wrap:wrap;justify-content:flex-end}.nav a{display:inline-flex;align-items:center;min-height:38px;padding:8px 11px;border:1px solid transparent;border-radius:13px;color:var(--muted);text-decoration:none;font-size:13px;font-weight:900}.nav a:hover,.nav a:focus-visible{border-color:rgba(244,122,0,.4);color:var(--orange2);outline:none;background:rgba(244,122,0,.08)}
.hero{margin-top:18px;padding:clamp(24px,5vw,50px);border:1px solid var(--line);border-radius:32px;background:linear-gradient(145deg,var(--panel),var(--panel2));box-shadow:var(--shadow);position:relative;overflow:hidden}.hero:before{content:"";position:absolute;inset:-170px -90px auto auto;width:360px;height:360px;border-radius:50%;background:radial-gradient(circle,rgba(255,174,53,.22),transparent 68%);pointer-events:none}.hero>*{position:relative}.eyebrow{display:inline-flex;align-items:center;gap:8px;padding:7px 11px;border:1px solid rgba(244,122,0,.36);border-radius:999px;background:rgba(244,122,0,.11);color:var(--orange2);font-size:12px;font-weight:1000}.hero h1{margin:16px 0 12px;font-size:clamp(34px,6vw,64px);line-height:1.08;letter-spacing:-.025em}.hero p{margin:0;max-width:820px;color:var(--muted);font-size:clamp(16px,2.2vw,19px);line-height:1.95;font-weight:750}.meta{display:flex;gap:8px;flex-wrap:wrap;margin-top:18px}.meta span{display:inline-flex;padding:7px 10px;border-radius:999px;border:1px solid var(--line);background:rgba(255,255,255,.045);color:#eadccc;font-size:12px;font-weight:900}
.layout{display:grid;grid-template-columns:minmax(0,1fr) 290px;gap:16px;align-items:start;margin-top:16px}
.content{display:grid;gap:14px}.card{padding:clamp(20px,3.5vw,30px);border:1px solid var(--line);border-radius:26px;background:linear-gradient(145deg,var(--panel),var(--panel2));box-shadow:0 16px 48px rgba(0,0,0,.20)}.card h2{margin:0 0 12px;color:var(--orange2);font-size:clamp(23px,3vw,32px)}.card h3{margin:22px 0 8px;font-size:19px}.card p,.card li{color:var(--muted);font-size:16px;line-height:1.95}.card p{margin:0 0 13px}.card ul,.card ol{margin:0;padding-right:22px}.card li+li{margin-top:9px}
.toc{position:sticky;top:94px;padding:18px;border:1px solid var(--line);border-radius:22px;background:rgba(17,20,29,.78);backdrop-filter:blur(16px)}.toc b{display:block;margin-bottom:10px;color:var(--orange2)}.toc a{display:block;padding:8px 10px;border-radius:12px;color:var(--muted);text-decoration:none;font-size:13px;font-weight:850}.toc a:hover{background:rgba(244,122,0,.08);color:var(--orange2)}
.examples{width:100%;border-collapse:separate;border-spacing:0;overflow:hidden;border:1px solid var(--line);border-radius:18px}.examples th,.examples td{padding:13px 14px;text-align:right;border-bottom:1px solid var(--line);vertical-align:top}.examples th{background:rgba(244,122,0,.10);color:var(--orange2);font-size:13px}.examples tr:last-child td{border-bottom:0}.examples td:first-child{direction:ltr;text-align:left;color:#fff;font-weight:1000}.examples td{color:var(--muted);line-height:1.65}
.practice{display:grid;gap:10px}.qa{border:1px solid var(--line);border-radius:17px;background:rgba(255,255,255,.04);padding:14px}.qa b{display:block;color:#fff;margin-bottom:7px}.answer{color:var(--green)!important;font-weight:850}
.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:13px;margin-top:16px}.lesson-card{display:flex;flex-direction:column;min-height:240px;padding:20px;border:1px solid var(--line);border-radius:23px;background:linear-gradient(145deg,var(--panel),var(--panel2));text-decoration:none;color:var(--text);box-shadow:0 14px 40px rgba(0,0,0,.18);transition:transform .16s ease,border-color .16s ease}.lesson-card:hover,.lesson-card:focus-visible{transform:translateY(-2px);border-color:rgba(255,174,53,.55);outline:none}.lesson-card small{color:var(--orange2);font-weight:1000}.lesson-card h2{font-size:20px;line-height:1.4;margin:12px 0 8px}.lesson-card p{color:var(--muted);line-height:1.75;margin:0}.lesson-card span{margin-top:auto;padding-top:14px;color:#ffd89d;font-size:13px;font-weight:950}
.notice{padding:16px 18px;border:1px solid rgba(244,122,0,.34);border-radius:18px;background:rgba(244,122,0,.09);color:#f1dfc7;line-height:1.85}
.form{display:grid;gap:12px}.field{display:grid;gap:7px}.field label{font-weight:900;color:#f6e7d5}.field input,.field textarea,.field select{width:100%;border:1px solid var(--line);background:rgba(255,255,255,.065);color:var(--text);border-radius:16px;padding:13px 14px;font:inherit;outline:none}.field textarea{min-height:150px;resize:vertical}.field input:focus,.field textarea:focus,.field select:focus{border-color:rgba(255,174,53,.54);box-shadow:0 0 0 4px rgba(244,122,0,.09)}.button{display:inline-flex;align-items:center;justify-content:center;min-height:48px;border:0;border-radius:16px;padding:12px 18px;background:linear-gradient(135deg,var(--orange),var(--orange2));color:#fff;font-weight:1000;cursor:pointer}.button:disabled{opacity:.55;cursor:wait}.status{min-height:24px;color:var(--muted);font-weight:850}.status.ok{color:var(--green)}.status.error{color:#ff9cab}
.footer{margin-top:18px;padding:20px;text-align:center;color:rgba(255,248,239,.55);font-size:12px;line-height:1.8}.footer nav{display:flex;justify-content:center;gap:12px;flex-wrap:wrap;margin-bottom:8px}.footer a{color:#d9c5aa;text-decoration:none;font-weight:850}.footer a:hover{color:var(--orange2)}
.sr-only{position:absolute!important;width:1px!important;height:1px!important;padding:0!important;margin:-1px!important;overflow:hidden!important;clip:rect(0,0,0,0)!important;white-space:nowrap!important;border:0!important}
@media(max-width:900px){.layout{grid-template-columns:1fr}.toc{position:relative;top:0;order:-1}.grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:620px){.shell{width:min(100% - 20px,1080px);padding-top:10px}.topbar{position:relative;top:0;align-items:flex-start}.brand-copy span{display:none}.nav{gap:3px}.nav a{padding:7px 8px;font-size:12px}.hero{border-radius:26px}.grid{grid-template-columns:1fr}.examples{display:block;overflow-x:auto}.examples th,.examples td{min-width:135px}.card{border-radius:22px}}