:root{--ink:#172033;--muted:#697586;--paper:#f8f7f4;--brand:#d97745;--purple:#6d3bf5;--nav:#101722;--card:#fff;--line:#e7e2da}
body{font-family:Inter,system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;background:var(--paper);color:var(--ink)}
.app-nav{background:rgba(16,23,34,.96);backdrop-filter:blur(10px)}.navbar-brand small{font-size:.62rem}.logo-mark{display:grid;place-items:center;width:34px;height:34px;border-radius:11px;background:linear-gradient(135deg,var(--brand),#f2a55f);color:white}
.hero{background:radial-gradient(circle at 12% 18%,rgba(217,119,69,.18),transparent 30%),radial-gradient(circle at 90% 8%,rgba(109,59,245,.13),transparent 28%),linear-gradient(135deg,#fff9f2,#f7f4ff);border-bottom:1px solid var(--line)}
.hero h1,.display-tight{letter-spacing:-.045em}.eyebrow{font-size:.78rem;font-weight:800;letter-spacing:.12em;text-transform:uppercase;color:#9a4f22}
.feature-card,.course-card,.panel{background:var(--card);border:1px solid var(--line);border-radius:20px;box-shadow:0 12px 35px rgba(38,31,21,.045)}.feature-card,.course-card{height:100%;transition:.2s}.feature-card:hover,.course-card:hover{transform:translateY(-3px);box-shadow:0 20px 45px rgba(38,31,21,.08)}
.level-pill{display:inline-grid;place-items:center;width:40px;height:40px;border-radius:13px;background:#fff0e4;color:#a3481d;font-weight:900}.muted{color:var(--muted)}
.lesson-content h2{margin-top:2rem;font-weight:800;letter-spacing:-.02em}.lesson-content p,.lesson-content li{line-height:1.75}.lesson-content pre{background:#101722;color:#d7e6dd;padding:18px;border-radius:15px;overflow:auto;border:1px solid #2b384b}.lesson-content code{font-size:.92rem}
.sticky-side{top:90px}.progress-thin{height:8px}.locked{opacity:.55}.checkmark{width:28px;height:28px;border-radius:50%;display:grid;place-items:center;background:#e9f8ef;color:#128454;font-weight:900}
.quiz-option{border:1px solid var(--line);border-radius:14px;padding:12px 14px;margin-bottom:9px;cursor:pointer;background:white}.quiz-option:hover{background:#fbf8f3}.quiz-option.correct{border-color:#138a5b;background:#ecfaf3}.quiz-option.wrong{border-color:#c8322c;background:#fff0ef}
.footer{background:#0d141e;color:#e8edf4}.footer a{display:block;color:#aeb8c5;text-decoration:none;margin:.45rem 0}.footer a:hover{color:white}
.auth-shell{min-height:calc(100vh - 72px);display:grid;place-items:center;padding:40px 0}.auth-card{max-width:520px;width:100%;background:white;border:1px solid var(--line);border-radius:22px;padding:28px;box-shadow:0 20px 60px rgba(0,0,0,.08)}
.kpi{background:white;border:1px solid var(--line);border-radius:18px;padding:20px}.kpi .num{font-size:2rem;font-weight:900;letter-spacing:-.04em}
.table-card{background:white;border:1px solid var(--line);border-radius:18px;overflow:hidden}.admin-sidebar a{display:block;padding:10px 12px;border-radius:10px;text-decoration:none;color:var(--ink)}.admin-sidebar a:hover{background:#f0ece5}
.breadcrumb a{text-decoration:none}.cta{background:linear-gradient(135deg,#161e2c,#2b1e4b);color:white;border-radius:28px}.search-result{padding:14px 0;border-bottom:1px solid var(--line)}
@media(max-width:767.98px){.hero h1{font-size:2.35rem}.auth-card{border-radius:16px}.sticky-side{position:static!important}}