:root{
    --primary:#6c5ce7;--primary-dark:#4f46e5;--pink:#ff4d8d;--blue:#2f80ed;--green:#12b886;--yellow:#ffd166;--dark:#172554;--text:#334155;--muted:#64748b;--bg:#f7f8ff;--card:#fff;--border:rgba(99,102,241,.16);--shadow:0 18px 45px rgba(15,23,42,.08);--shadow-soft:0 10px 26px rgba(15,23,42,.07)
}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{font-family:'Prompt',system-ui,sans-serif;background:radial-gradient(circle at top left,rgba(255,77,141,.08),transparent 28%),radial-gradient(circle at top right,rgba(108,92,231,.1),transparent 30%),linear-gradient(180deg,#fff 0%,var(--bg) 100%);color:var(--text);min-height:100vh;display:flex;flex-direction:column}main{flex:1 0 auto}a{text-decoration:none}.text-gradient{background:linear-gradient(90deg,var(--pink),var(--primary));-webkit-background-clip:text;background-clip:text;color:transparent}.site-header{background:rgba(255,255,255,.9);backdrop-filter:blur(16px);border-bottom:1px solid rgba(226,232,240,.9);box-shadow:0 8px 24px rgba(15,23,42,.04)}.navbar{padding:12px 0}.brand-icon{width:48px;height:48px;border-radius:17px;background:linear-gradient(135deg,var(--primary),var(--pink));display:inline-flex;align-items:center;justify-content:center;color:#fff;box-shadow:0 12px 24px rgba(108,92,231,.28);font-size:1.25rem}.brand-title{display:block;font-size:1.06rem;font-weight:900;color:var(--dark);line-height:1.2}.brand-subtitle{display:block;font-size:.74rem;color:var(--pink);font-weight:600}.navbar-toggler{width:44px;height:44px;border:0;border-radius:14px;background:#eef2ff;color:var(--primary)}.nav-link{color:#475569!important;font-weight:700;border-radius:999px;padding:10px 14px!important;transition:.22s}.nav-link:hover{background:#eef2ff;color:var(--primary-dark)!important;transform:translateY(-1px)}.nav-link.active{background:linear-gradient(135deg,var(--primary),var(--primary-dark));color:#fff!important;box-shadow:0 10px 20px rgba(108,92,231,.22)}.btn-admin-link{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-height:42px;padding:10px 18px;border-radius:999px;background:linear-gradient(135deg,var(--primary),var(--blue));color:#fff!important;font-weight:800;box-shadow:0 12px 24px rgba(47,128,237,.22)}.section{padding:46px 0}.section-sm{padding:30px 0}.hero{position:relative;margin-top:24px;padding:38px;border-radius:36px;background:radial-gradient(circle at 14% 20%,rgba(255,255,255,.92),transparent 24%),radial-gradient(circle at 90% 12%,rgba(255,255,255,.72),transparent 28%),linear-gradient(135deg,#fff5d7 0%,#ffe0eb 45%,#e6e2ff 100%);box-shadow:var(--shadow);overflow:hidden;border:1px solid rgba(255,255,255,.78)}.hero:before{content:"";position:absolute;right:-80px;top:-90px;width:260px;height:260px;border-radius:999px;background:rgba(255,255,255,.45)}.hero:after{content:"";position:absolute;left:42%;bottom:-95px;width:180px;height:180px;border-radius:999px;background:rgba(255,77,141,.1)}.hero>*{position:relative;z-index:2}.hero-badge{display:inline-flex;align-items:center;gap:8px;padding:9px 15px;border-radius:999px;background:rgba(255,255,255,.84);color:#db2777;font-weight:800;box-shadow:0 8px 18px rgba(219,39,119,.1);margin-bottom:16px}.hero h1{font-size:clamp(2.35rem,5.5vw,4.65rem);line-height:1.08;letter-spacing:-1.4px;color:#19235c;font-weight:900}.hero p{font-size:1.12rem;line-height:1.85;color:#475569;max-width:650px}.hero-visual{min-height:360px;display:flex;align-items:center;justify-content:center}.math-board{width:min(100%,480px);padding:26px;border-radius:32px;background:rgba(255,255,255,.78);border:1px solid rgba(255,255,255,.95);box-shadow:0 20px 45px rgba(15,23,42,.09);transform:rotate(1.5deg)}.math-board .formula{font-size:clamp(2rem,4vw,4rem);font-weight:900;color:#1e1b4b;letter-spacing:-1px}.math-chip{display:inline-flex;align-items:center;gap:8px;padding:10px 14px;border-radius:18px;background:#eef2ff;color:#4f46e5;font-weight:800;margin:5px}.btn-main,.btn-soft{display:inline-flex;align-items:center;justify-content:center;gap:9px;min-height:50px;padding:12px 24px;border-radius:999px;font-weight:900;transition:.25s}.btn-main{color:#fff;background:linear-gradient(135deg,var(--pink),var(--primary));box-shadow:0 14px 26px rgba(108,92,231,.28)}.btn-main:hover{color:#fff;transform:translateY(-3px);box-shadow:0 18px 34px rgba(108,92,231,.36)}.btn-soft{color:#4f46e5;background:#fff;border:1px solid rgba(99,102,241,.14);box-shadow:var(--shadow-soft)}.btn-soft:hover{color:#312e81;transform:translateY(-3px)}.stat-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px}.stat-card{padding:20px;border-radius:26px;background:#fff;border:1px solid var(--border);box-shadow:var(--shadow-soft)}.stat-card strong{display:block;font-size:1.8rem;color:#1e1b4b;font-weight:900}.stat-card span{color:#64748b;font-weight:700}.section-head{display:flex;justify-content:space-between;align-items:end;gap:18px;margin-bottom:22px}.section-title{margin:0;color:#172554;font-weight:900;letter-spacing:-.4px}.section-desc{color:#64748b;margin:8px 0 0;line-height:1.7}.content-card{background:#fff;border:1px solid var(--border);border-radius:28px;box-shadow:var(--shadow-soft);overflow:hidden;transition:.25s}.content-card.d-block,.content-card.h-100{height:100%}.content-card:not(.d-block):not(.h-100){height:auto!important}.detail-article,.content-card.card-pad{position:relative;z-index:2}.site-footer{position:relative;z-index:1}.content-card:hover{transform:translateY(-5px);box-shadow:var(--shadow)}.card-pad{padding:24px}.icon-box{width:54px;height:54px;border-radius:20px;display:inline-flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#eef2ff,#ffe7f0);color:var(--primary);font-size:1.35rem}.badge-soft{display:inline-flex;align-items:center;gap:6px;padding:7px 11px;border-radius:999px;background:#eef2ff;color:#4f46e5;font-weight:800;font-size:.78rem}.badge-grade{background:#fff7ed;color:#c2410c}.card-title{font-weight:900;color:#1e1b4b}.card-text{color:#64748b;line-height:1.75}.filter-box{background:#fff;border:1px solid var(--border);border-radius:28px;padding:20px;box-shadow:var(--shadow-soft);margin-bottom:24px}.form-control,.form-select{border-radius:16px;border:1px solid #e2e8f0;padding:12px 14px}.form-control:focus,.form-select:focus{border-color:#a5b4fc;box-shadow:0 0 0 .25rem rgba(99,102,241,.14)}.page-hero{padding:42px 0 24px}.page-hero-box{border-radius:34px;background:linear-gradient(135deg,#eef2ff,#fff7ed);padding:32px;box-shadow:var(--shadow-soft);border:1px solid rgba(255,255,255,.9)}.detail-article{background:#fff;border:1px solid var(--border);border-radius:32px;padding:30px;box-shadow:var(--shadow-soft)}.article-body{font-size:1.03rem;line-height:1.9;color:#334155}.article-body p{margin-bottom:1rem}.video-wrap{position:relative;width:100%;padding-top:56.25%;border-radius:26px;overflow:hidden;background:#0f172a;box-shadow:var(--shadow-soft)}.video-wrap iframe{position:absolute;inset:0;width:100%;height:100%;border:0}.download-row{display:flex;align-items:center;gap:14px;padding:16px;border-radius:22px;background:#fff;border:1px solid var(--border);box-shadow:var(--shadow-soft)}.download-row .file-icon{width:50px;height:50px;border-radius:17px;background:#eef2ff;color:#4f46e5;display:inline-flex;align-items:center;justify-content:center}.empty-box{padding:40px;border-radius:28px;background:#fff;border:1px dashed #cbd5e1;color:#64748b;text-align:center}.site-footer{margin-top:32px;padding:36px 0 18px;background:radial-gradient(circle at 10% 10%,rgba(255,77,141,.25),transparent 28%),radial-gradient(circle at 90% 0%,rgba(47,128,237,.25),transparent 30%),linear-gradient(135deg,#172554 0%,#312e81 48%,#4c1d95 100%)}.footer-card{padding:24px;border-radius:32px;background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.16);box-shadow:0 18px 45px rgba(15,23,42,.2);backdrop-filter:blur(14px)}.footer-icon{width:54px;height:54px;border-radius:18px;display:inline-flex;align-items:center;justify-content:center;background:linear-gradient(135deg,#ff4d8d,#6c5ce7);color:#fff;font-size:1.45rem}.text-white-75{color:rgba(255,255,255,.76)}.footer-title{color:#fff;font-weight:900;margin-bottom:12px}.site-footer a{display:block;color:rgba(255,255,255,.74);font-weight:600;margin-bottom:8px}.site-footer a:hover{color:#fff}.visitor-pill,.footer-contact{display:inline-flex!important;align-items:center;gap:9px;padding:11px 15px;border-radius:999px;background:rgba(255,255,255,.13);border:1px solid rgba(255,255,255,.18);color:#fff!important;font-weight:800}.admin-body{background:#f7f8ff}.admin-shell{min-height:100vh}.admin-sidebar{background:#172554;color:#fff;min-height:100vh;padding:20px;position:sticky;top:0}.admin-sidebar a{display:flex;align-items:center;gap:10px;color:rgba(255,255,255,.78);padding:12px 14px;border-radius:16px;font-weight:700;margin-bottom:6px}.admin-sidebar a:hover,.admin-sidebar a.active{background:rgba(255,255,255,.12);color:#fff}.admin-main{padding:26px}.admin-card{background:#fff;border:1px solid var(--border);border-radius:26px;box-shadow:var(--shadow-soft);padding:24px}.admin-table td,.admin-table th{vertical-align:middle}.login-page{min-height:100vh;display:flex;align-items:center;background:radial-gradient(circle at top left,rgba(255,77,141,.16),transparent 30%),radial-gradient(circle at bottom right,rgba(108,92,231,.18),transparent 34%),#f8fafc}.login-card{max-width:460px;margin:auto;background:#fff;border:1px solid var(--border);border-radius:32px;padding:30px;box-shadow:var(--shadow)}
@media (max-width:1199.98px){.navbar-collapse{margin-top:14px;padding:14px;border-radius:24px;background:#fff;border:1px solid #e2e8f0;box-shadow:var(--shadow)}.btn-admin-link{width:100%;border-radius:16px}.nav-link{border-radius:16px}}
@media (max-width:991.98px){.hero{padding:28px}.hero-visual{min-height:auto;margin-top:20px}.stat-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.section-head{align-items:start;flex-direction:column}.admin-sidebar{min-height:auto;position:static}.admin-main{padding:18px}}
@media (max-width:575.98px){.brand-title{font-size:.94rem}.brand-subtitle{font-size:.68rem}.brand-icon{width:42px;height:42px}.hero{border-radius:26px;padding:22px}.hero h1{font-size:2.25rem}.stat-grid{grid-template-columns:1fr}.card-pad{padding:20px}.page-hero-box,.detail-article{padding:22px;border-radius:24px}.site-footer{padding:28px 0 14px}.footer-card{padding:20px;border-radius:24px}}
.system-link-card{position:relative;min-height:260px;display:flex!important;flex-direction:column}.system-link-card .link-go{margin-top:auto;display:inline-flex;align-items:center;gap:8px;color:#4f46e5;font-weight:900}.system-link-card:hover .link-go{color:#312e81}@media (max-width:575.98px){.system-link-card{min-height:auto}}