:root{--bg:#f9fafb;--text:#1f2937;--header-bg:#fff;--header-border:#e5e7eb;--link:#2563eb;--card-bg:#fff;--card-border:#e5e7eb;--card-text:#1f2937;--cta-bg:#2563eb;--cta-hover-bg:#1e40af;--cta-text:#fff;--footer-bg:#f9fafb;--footer-text:#6b7280;--input-bg:#fff;--input-border:#d1d5db;--input-text:#1f2937}.dark{--bg:#1f2937;--text:#f3f4f6;--header-bg:#111827;--header-border:#374151;--link:#3b82f6;--card-bg:#111827;--card-border:#374151;--card-text:#f3f4f6;--cta-bg:#3b82f6;--cta-hover-bg:#2563eb;--cta-text:#fff;--footer-bg:#111827;--footer-text:#9ca3af;--input-bg:#1f2937;--input-border:#374151;--input-text:#f3f4f6}html,body{background-color:var(--bg);color:var(--text);margin:0;padding:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Open Sans,Helvetica Neue,sans-serif;line-height:1.6}*{box-sizing:border-box}a{color:var(--link);text-decoration:none}header{background:var(--header-bg);border-bottom:1px solid var(--header-border);padding:1rem 2rem}nav{flex-wrap:wrap;justify-content:space-between;align-items:center;display:flex}nav a{margin-right:1rem;font-weight:500}main{max-width:960px;margin:0 auto;padding:2rem 1rem}footer{background:var(--footer-bg);border-top:1px solid var(--header-border);color:var(--footer-text);padding:1rem 2rem;font-size:.875rem}.card{background:var(--card-bg);border:1px solid var(--card-border);border-radius:.5rem;flex-direction:column;justify-content:space-between;padding:1.5rem;display:flex}.card h3{color:var(--card-text);margin-top:0;margin-bottom:.5rem;font-size:1.25rem}.card ul{margin-bottom:1.5rem;padding-left:0;list-style:none}.card li{margin-bottom:.5rem}.cta{background:var(--cta-bg);color:var(--cta-text);text-align:center;border-radius:.375rem;padding:.75rem 1.5rem;font-weight:600;transition:background-color .2s;display:inline-block}.cta:hover{background:var(--cta-hover-bg)}.theme-toggle{cursor:pointer;color:var(--text);background:0 0;border:none;padding:.5rem 1rem;font-size:1rem}.container{max-width:960px;margin:0 auto;padding:2rem 1rem}.grid{grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:1.5rem;display:grid}