:root{--bg:#0f1224;--panel:#151936;--panel2:#20254d;--text:#eef1ff;--muted:#aeb6e6;--line:rgba(255,255,255,.1);--shadow:0 20px 50px rgba(0,0,0,.28);--radius:16px;--sidebar:300px}*{box-sizing:border-box}body{margin:0;background:radial-gradient(circle at top,#27306b,#0f1224 45%);color:var(--text);font-family:Inter,system-ui,sans-serif;min-height:100vh}button,input{font:inherit}button{border:1px solid var(--line);background:#2a2f61;color:var(--text);border-radius:12px;padding:.72rem .9rem;cursor:pointer}.outline{background:transparent}.primary{background:#b8c5ff;color:#0c1231;font-weight:800}.mini{padding:.45rem .65rem;border-radius:10px;font-size:.86rem}input{width:100%;background:#0f1330;border:1px solid var(--line);color:var(--text);border-radius:12px;padding:.82rem .9rem}.app{display:grid;grid-template-columns:var(--sidebar) minmax(0,1fr);min-height:100vh}.sidebar{position:sticky;top:0;height:100vh;background:rgba(12,16,40,.92);border-right:1px solid var(--line);padding:1rem;overflow:auto}.brand{display:flex;gap:.8rem;align-items:center;padding:.4rem .2rem 1rem}.logo{width:42px;height:42px;border-radius:14px;background:#b8c5ff;color:#111;display:grid;place-items:center;font-weight:900}.brand p,.muted{color:var(--muted)}.side-actions{display:grid;gap:.55rem;margin-bottom:1rem}.cat-row{padding:.55rem .45rem;color:var(--muted);cursor:pointer}.topbar{position:sticky;top:0;background:rgba(10,12,28,.9);border-bottom:1px solid var(--line);padding:.9rem 1.1rem;display:grid;grid-template-columns:auto minmax(180px,760px) auto;gap:.8rem}.search-wrap{position:relative}.suggestions{position:absolute;top:calc(100% + .45rem);left:0;right:0;background:#171b3a;border:1px solid var(--line);border-radius:14px;display:none}.suggestions.active{display:block}.userbar{display:flex;gap:.5rem;align-items:center;justify-content:flex-end}.content{padding:1.2rem;max-width:1320px;margin:auto}.grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1rem}.card{border:1px solid var(--line);background:rgba(23,29,66,.88);border-radius:18px;padding:1rem}.hero{margin-bottom:1rem;background:linear-gradient(135deg,#2b3472,#3d4ca3)}.subjects-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1rem}.subject-card{text-align:left;padding:1rem;background:linear-gradient(170deg,#1c2455,#28337c)}.footer{border-top:1px solid var(--line);margin-top:2rem;padding:2rem 1.2rem;background:#10142f}.footer-grid{display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:1rem;max-width:1320px;margin:auto}.footer a{display:block;color:var(--muted);text-decoration:none;margin:.45rem 0}.modal{position:fixed;inset:0;background:rgba(0,0,0,.66);z-index:60;display:none;align-items:center;justify-content:center;padding:1rem}.modal.active{display:flex}.modal-card{background:#171b3a;border:1px solid var(--line);border-radius:20px;max-width:560px;width:min(100%,560px);padding:1rem}.single-auth{display:grid;gap:.7rem;margin-top:.6rem}.toast{position:fixed;right:1rem;bottom:1rem;background:#f4f4f5;color:#111;padding:.85rem 1rem;border-radius:14px;z-index:90;display:none}.toast.active{display:block}.mobile-menu{display:none}@media(max-width:900px){.app{grid-template-columns:1fr}.sidebar{position:fixed;left:-320px;transition:left .2s}.sidebar.open{left:0}.mobile-menu{display:inline-flex}.grid,.footer-grid,.subjects-grid{grid-template-columns:1fr}}