:root { color-scheme: dark; } * { box-sizing: border-box; } body { margin: 0; min-height: 100vh; font-family: Inter, system-ui, sans-serif; background: radial-gradient(circle at top left, rgba(59, 130, 246, 0.18), transparent 24%), linear-gradient(180deg, #020617 0%, #0f172a 56%, #111827 100%); color: #e2e8f0; overflow-x: hidden; } a { color: inherit; text-decoration: none; } .wrap { width: min(1120px, calc(100% - 1rem)); margin: 0 auto; padding: 28px 0 40px; } h1 { margin: 0; font-size: clamp(2rem, 8vw, 3rem); letter-spacing: -0.04em; } .lede { max-width: 42ch; margin: 0.6rem 0 0; color: #94a3b8; line-height: 1.7; } .toolbar { display: grid; gap: 0.75rem; margin-top: 1.25rem; } .search { width: 100%; min-height: 48px; padding: 0.9rem 1rem; border: 1px solid rgba(148,163,184,.18); border-radius: 16px; background: rgba(15,23,42,.72); color: #e2e8f0; font: inherit; } .search::placeholder { color: #94a3b8; } .search:focus { outline: 2px solid rgba(96, 165, 250, 0.55); outline-offset: 2px; } .meta { margin: 0; color: #94a3b8; font-size: 0.95rem; } .grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin-top: 18px; } .wrap { max-width: 980px; margin: 0 auto; padding: 48px 20px; } .card { min-height: 126px; padding: 20px; border: 1px solid rgba(148,163,184,.16); border-radius: 20px; background: rgba(15,23,42,.68); display: flex; flex-direction: column; justify-content: space-between; gap: 0.5rem; transition: transform 180ms ease, border-color 180ms ease, background-color 180ms ease; } .card:hover { transform: translateY(-2px); border-color: rgba(96,165,250,.44); background: rgba(15,23,42,.82); } .card h2 { margin: 0; font-size: 1.15rem; } .card p { margin: 0; color: #94a3b8; line-height: 1.7; } .home-link { display: inline-flex; margin-top: 24px; color: #93c5fd; min-height: 44px; align-items: center; } @media (max-width: 480px) { .wrap { width: min(100% - 0.75rem, 1120px); padding-top: 20px; } .grid { grid-template-columns: 1fr; gap: 12px; } .card { min-height: 112px; padding: 18px; } .home-link { margin-top: 18px; } } .card p { margin: 0; color: #94a3b8; line-height: 1.7; } .home-link { display: inline-block; margin-top: 24px; color: #93c5fd; }

Browse the organized subject folders.

Topics

Math

Physics

Computer Science