:root{--bg:#f7f9fc;--card:#fff;--text:#162033;--muted:#687489;--line:#e5eaf1;--navy:#102a43;--blue:#2d6cdf;--cyan:#27b3c2;--green:#1ea672;--orange:#f59e0b;--purple:#7857d9;--shadow:0 14px 40px rgba(16,42,67,.08)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,Arial,sans-serif;background:var(--bg);color:var(--text);line-height:1.55}a{color:inherit;text-decoration:none}.container{width:min(1180px,calc(100% - 36px));margin:auto}.announcement{background:#102a43;color:#fff;padding:8px 18px;display:flex;justify-content:center;gap:25px;font-size:13px}.announcement a{color:#92ddec;font-weight:700}.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.96);backdrop-filter:blur(12px);border-bottom:1px solid var(--line)}.nav-wrap{height:76px;display:flex;align-items:center;gap:26px}.brand{display:flex;align-items:center;gap:10px;min-width:max-content}.brand-mark{width:42px;height:42px;display:grid;place-items:center;border-radius:12px;background:linear-gradient(135deg,var(--blue),var(--cyan));color:#fff;font-weight:800}.brand b{font-family:Merriweather,serif;font-size:21px}.brand small{display:block;font-size:10px;letter-spacing:1.5px;color:var(--muted);text-transform:uppercase}.main-nav{display:flex;align-items:center;gap:23px;margin:auto;font-size:14px;font-weight:600}.main-nav>a,.dropdown>button{border:0;background:none;padding:26px 0;cursor:pointer;color:var(--text);font:inherit}.main-nav>a:hover,.dropdown button:hover{color:var(--blue)}.dropdown{position:relative}.dropdown-menu{display:none;position:absolute;top:67px;left:-18px;min-width:220px;background:#fff;border:1px solid var(--line);box-shadow:var(--shadow);border-radius:14px;padding:10px}.dropdown:hover 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0}.section.white{background:#fff}.section-head{display:flex;align-items:end;justify-content:space-between;gap:20px;margin-bottom:27px}.section-head p{color:var(--muted);max-width:650px;margin:0}.grid{display:grid;gap:20px}.grid-3{grid-template-columns:repeat(3,1fr)}.grid-4{grid-template-columns:repeat(4,1fr)}.card{background:var(--card);border:1px solid var(--line);border-radius:18px;padding:20px;box-shadow:0 7px 24px rgba(16,42,67,.04)}.card:hover{transform:translateY(-3px);transition:.2s;box-shadow:var(--shadow)}.feature-icon{font-size:28px;width:52px;height:52px;border-radius:14px;background:#edf4ff;display:grid;place-items:center;margin-bottom:14px}.muted{color:var(--muted)}.subject-card{padding:22px;display:flex;gap:14px;align-items:center}.subject-icon{width:45px;height:45px;border-radius:12px;display:grid;place-items:center;background:#eef4ff;font-size:20px}.book-card{padding:0;overflow:hidden}.book-cover{height:220px;display:flex;align-items:flex-end;padding:17px;color:#fff;background:linear-gradient(145deg,#234a73,#2d6cdf);position:relative}.book-cover.math{background:linear-gradient(145deg,#4b2c7d,#8a60d1)}.book-cover.physics{background:linear-gradient(145deg,#154a49,#21a08d)}.book-cover.chem{background:linear-gradient(145deg,#80431e,#ed8b35)}.book-cover.history{background:linear-gradient(145deg,#6f263f,#c55271)}.book-cover.code{background:linear-gradient(145deg,#1f2937,#596579)}.book-cover 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300px;gap:20px}.class-stage{min-height:540px;background:#152940;border-radius:20px;padding:20px;color:#fff}.stage-board{height:340px;border:1px solid #36516e;border-radius:16px;padding:25px;background:#1c3552}.class-panel{background:#fff;border:1px solid var(--line);border-radius:20px;padding:18px}.student-list{display:grid;gap:10px}.student{display:flex;align-items:center;gap:10px;padding:8px;background:#f7f9fc;border-radius:10px}.dashboard-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}.metric b{font-size:28px;display:block}.progress{height:8px;background:#e8edf4;border-radius:10px;overflow:hidden}.progress i{display:block;height:100%;background:var(--blue)}.form-card{max-width:520px;margin:45px auto;background:#fff;border:1px solid var(--line);border-radius:20px;padding:30px;box-shadow:var(--shadow)}.form-group{display:grid;gap:7px;margin:14px 0}.form-group label{font-size:13px;font-weight:700}.form-group input,.form-group textarea,.form-group select{width:100%;padding:13px;border:1px solid var(--line);border-radius:10px}.footer{background:#0d2236;color:#dce7f1;margin-top:70px;padding:58px 0 20px}.footer-grid{display:grid;grid-template-columns:1.5fr repeat(3,1fr);gap:35px}.footer h4{color:#fff}.footer a{display:block;color:#b8c9d8;font-size:13px;margin:10px 0}.footer p{color:#9fb3c5;max-width:360px}.footer-brand b{color:#fff}.footer-brand small{color:#9fb3c5}.footer-bottom{border-top:1px solid #23394d;margin-top:35px;padding-top:18px;display:flex;justify-content:space-between;color:#8fa5b7;font-size:12px}.socials{display:flex;gap:8px}.socials span{width:32px;height:32px;border:1px solid #31485d;border-radius:8px;display:grid;place-items:center}.notice{padding:12px 14px;border-radius:10px;background:#eef7ff;color:#205b96;margin:12px 0;font-size:13px}.empty{padding:30px;text-align:center;color:var(--muted)}body.dark{--bg:#0f1720;--card:#152231;--text:#e6eef7;--muted:#9cb0c3;--line:#2a3a4a}.dark .site-header,.dark 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