:root{
  --bg:#08101c;--bg2:#0e1728;--panel:#111c30;--panel2:#16243d;--card:#13213a;
  --border:#263a5a;--soft:#92a7c7;--text:#eef5ff;--primary:#4da3ff;--primary2:#87cbff;
  --accent:#72e8ff;--gold:#f4c24f;--success:#43d69f;--danger:#ff8f8f;
  --shadow:0 18px 42px rgba(0,0,0,.35);--radius:20px;--max:1180px;
}
*{box-sizing:border-box} html{scroll-behavior:smooth}
body{margin:0;font-family:Inter,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
background:radial-gradient(circle at top left,rgba(77,163,255,.12),transparent 34%),linear-gradient(180deg,#07101b,#0b1423);
color:var(--text);line-height:1.68}
a{text-decoration:none;color:inherit} img{max-width:100%;display:block}.container{width:min(var(--max),calc(100% - 32px));margin:auto}
.site-header{position:sticky;top:0;z-index:1000;backdrop-filter:blur(14px);background:rgba(8,16,28,.9);border-bottom:1px solid rgba(255,255,255,.07)}
.nav{min-height:74px;display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{display:flex;align-items:center;gap:12px;font-weight:800;flex-shrink:0}
.brand-logo{width:42px;height:42px;border-radius:13px;display:grid;place-items:center;background:linear-gradient(135deg,#198fff,#68d5ff);color:#fff;font-weight:800;box-shadow:0 10px 24px rgba(25,143,255,.3)}
.brand-text{font-family:Rajdhani,sans-serif;font-size:1.4rem}.brand-text span{color:var(--primary2)}
.nav-links{display:flex;align-items:center;gap:17px;flex-wrap:wrap;justify-content:flex-end}.nav-links a{color:#d5e4fb;font-size:.94rem}.nav-links a:hover{color:#fff}.nav-links .active{color:var(--accent);font-weight:700}
.nav-cta{padding:10px 16px;border-radius:999px;background:linear-gradient(135deg,var(--primary),#3a86ff);color:#fff!important;font-weight:700}
.menu-toggle{display:none;width:46px;height:46px;border-radius:12px;border:1px solid rgba(255,255,255,.08);background:rgba(255,255,255,.03);padding:0;cursor:pointer;align-items:center;justify-content:center;flex-direction:column;gap:5px}
.menu-toggle span{display:block;width:20px;height:2px;background:#eaf3ff;border-radius:999px}.mobile-menu{display:none;border-top:1px solid rgba(255,255,255,.06);background:rgba(8,16,28,.98)}.mobile-menu.open{display:block}.mobile-menu-inner{width:min(var(--max),calc(100% - 32px));margin:auto;padding:14px 0 18px;display:grid;gap:10px}.mobile-menu-inner a{padding:11px 14px;border-radius:12px;background:rgba(255,255,255,.03);color:#dce9fb}
.breadcrumbs{padding:20px 0 0;color:var(--soft);font-size:.9rem}.breadcrumbs a{color:var(--primary2)}
.hero{padding:60px 0 36px}.hero-grid{display:grid;grid-template-columns:1.16fr .84fr;gap:32px;align-items:center}
.eyebrow{display:inline-flex;padding:7px 12px;border:1px solid rgba(114,232,255,.25);background:rgba(114,232,255,.08);color:var(--accent);border-radius:999px;font-size:.78rem;font-weight:700;letter-spacing:.04em;text-transform:uppercase}
h1{margin:17px 0 14px;font-size:clamp(2.45rem,5vw,4.35rem);line-height:1.04;letter-spacing:-.035em}h2{line-height:1.15;letter-spacing:-.02em}.highlight{color:var(--primary2)}
.lead{margin:0 0 22px;color:var(--soft);font-size:1.06rem;max-width:760px}.hero-actions,.button-row{display:flex;flex-wrap:wrap;gap:12px;margin-top:22px}.btn{display:inline-flex;align-items:center;justify-content:center;padding:13px 20px;border-radius:14px;font-weight:700}.btn-primary{background:linear-gradient(135deg,var(--primary),#3a86ff);color:#fff;box-shadow:0 14px 28px rgba(77,163,255,.22)}.btn-secondary{border:1px solid var(--border);background:rgba(255,255,255,.03);color:#fff}.btn-small{padding:10px 14px;font-size:.92rem}
.hero-card,.card,.lesson-card,.article,.sidebar,.callout,.code-panel,.summary-box{background:linear-gradient(180deg,rgba(17,27,45,.92),rgba(13,21,35,.97));border:1px solid rgba(255,255,255,.07);border-radius:22px;box-shadow:var(--shadow)}
.hero-card{padding:24px}.hero-card h2{margin:4px 0 10px;font-size:1.55rem}.hero-card ul{padding-left:20px;margin:12px 0 0;color:#d9e7fb}.hero-card li{margin:7px 0}
.section{padding:38px 0}.section-head{margin-bottom:22px}.section-head h2{margin:0 0 9px;font-size:clamp(1.75rem,3vw,2.5rem)}.section-head p{margin:0;color:var(--soft);max-width:820px}
.course-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}.lesson-card{padding:22px;display:flex;gap:17px;align-items:flex-start}.lesson-num{width:44px;height:44px;flex:0 0 44px;border-radius:14px;display:grid;place-items:center;background:linear-gradient(135deg,var(--primary2),var(--accent));color:#06111d;font-weight:800}.lesson-card h3{margin:0 0 6px;font-size:1.18rem}.lesson-card p{margin:0 0 10px;color:var(--soft);font-size:.94rem}.lesson-card a{color:var(--accent);font-weight:700}
.info-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.card{padding:22px}.card h3{margin:0 0 8px}.card p{margin:0;color:var(--soft)}
.course-layout{display:grid;grid-template-columns:260px minmax(0,1fr);gap:28px;align-items:start;padding:26px 0 54px}.sidebar{padding:18px;position:sticky;top:94px}.sidebar h3{margin:0 0 12px}.lesson-list{display:grid;gap:5px}.lesson-list a{padding:9px 10px;border-radius:10px;color:#c8d8ef;font-size:.9rem}.lesson-list a:hover{background:rgba(255,255,255,.05)}.lesson-list a.current{background:rgba(77,163,255,.14);color:#fff;border:1px solid rgba(77,163,255,.2)}
.article{padding:30px;min-width:0}.article h1{font-size:clamp(2rem,4vw,3.2rem);margin-top:7px}.article h2{font-size:1.55rem;margin-top:34px;margin-bottom:10px}.article h3{font-size:1.15rem;margin-top:25px}.article p,.article li{color:#d5e4f7}.article ul,.article ol{padding-left:23px}.article li{margin:6px 0}.article strong{color:#fff}.article a{color:var(--accent)}
.lesson-kicker{color:var(--accent);font-weight:700;font-size:.9rem;text-transform:uppercase;letter-spacing:.05em}.meta{display:flex;flex-wrap:wrap;gap:10px;margin:16px 0 24px}.meta span{padding:7px 10px;border-radius:999px;background:rgba(255,255,255,.04);border:1px solid rgba(255,255,255,.07);color:#cddcf0;font-size:.84rem}
.callout{padding:18px 20px;margin:22px 0;box-shadow:none}.callout.tip{border-color:rgba(67,214,159,.25);background:rgba(67,214,159,.07)}.callout.note{border-color:rgba(77,163,255,.28);background:rgba(77,163,255,.08)}.callout.warn{border-color:rgba(244,194,79,.28);background:rgba(244,194,79,.07)}.callout strong{display:block;margin-bottom:4px}.callout p{margin:0;color:#dbe8f8}
pre{margin:18px 0;overflow:auto;border-radius:16px;border:1px solid #263a5a;background:#07101b;padding:18px;box-shadow:inset 0 0 0 1px rgba(255,255,255,.015)}code{font-family:"JetBrains Mono",Consolas,monospace;font-size:.9rem}pre code{color:#d6e7ff;white-space:pre}.inline-code{font-family:"JetBrains Mono",monospace;background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.07);padding:2px 6px;border-radius:6px;color:#fff;font-size:.9em}
.table-wrap{overflow-x:auto;margin:18px 0}table{width:100%;border-collapse:collapse;background:rgba(255,255,255,.02);border:1px solid var(--border)}th,td{padding:12px 14px;border-bottom:1px solid var(--border);text-align:left;vertical-align:top}th{background:rgba(77,163,255,.08);color:#fff}td{color:#d4e2f4}
.exercise{margin-top:30px;padding:22px;border-radius:18px;border:1px solid rgba(114,232,255,.2);background:rgba(114,232,255,.06)}.exercise h3{margin-top:0}
.lesson-nav{display:flex;justify-content:space-between;gap:12px;margin-top:34px;padding-top:22px;border-top:1px solid rgba(255,255,255,.08)}.lesson-nav a{display:block;max-width:48%;padding:12px 15px;border:1px solid var(--border);border-radius:13px;background:rgba(255,255,255,.03);font-weight:700}.lesson-nav .next{text-align:right;margin-left:auto}
.footer{margin-top:40px;border-top:1px solid rgba(255,255,255,.08);background:rgba(5,10,18,.72)}.footer-grid{padding:30px 0;display:grid;grid-template-columns:2fr 1fr 1fr;gap:24px}.footer h4{margin:0 0 10px}.footer p,.footer a{color:var(--soft);font-size:.93rem}.footer ul{list-style:none;padding:0;margin:0;display:grid;gap:7px}.footer-bottom{padding:15px 0 22px;border-top:1px solid rgba(255,255,255,.06);color:var(--soft);font-size:.88rem}
@media(max-width:900px){.hero-grid,.info-grid,.course-layout,.footer-grid{grid-template-columns:1fr}.sidebar{position:static}.course-grid{grid-template-columns:1fr}.nav-links{display:none}.menu-toggle{display:flex}.hero{padding-top:44px}.article{padding:22px}}
@media(max-width:600px){h1{font-size:2.4rem}.lesson-card{padding:18px}.article{padding:18px}.lesson-nav{flex-direction:column}.lesson-nav a{max-width:100%}.lesson-nav .next{text-align:left;margin-left:0}}