:root {
    --zemin: #f5f7fb;
    --yuzey: #ffffff;
    --metin: #1b2433;
    --soluk: #5b6678;
    --vurgu: #2f6fed;
    --kenar: #e2e7f0;
    color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
    :root {
        --zemin: #0f141c;
        --yuzey: #171e2a;
        --metin: #e6ebf3;
        --soluk: #98a3b6;
        --vurgu: #6b9bff;
        --kenar: #263042;
    }
}

* { box-sizing: border-box; }

body {
    margin: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background: var(--zemin);
    color: var(--metin);
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
    line-height: 1.5;
}

main {
    flex: 1;
    width: 100%;
    max-width: 960px;
    margin: 0 auto;
    padding: 72px 16px 48px;
}

header { text-align: center; margin-bottom: 48px; }
.ust { margin: 0; color: var(--vurgu); font-weight: 600; letter-spacing: .08em; text-transform: uppercase; font-size: .85rem; }
h1 { margin: 8px 0 12px; font-size: clamp(2rem, 6vw, 3rem); }
.alt { margin: 0; color: var(--soluk); font-size: 1.1rem; }

.kartlar {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 20px;
}

.kart {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding: 24px;
    background: var(--yuzey);
    border: 1px solid var(--kenar);
    border-radius: 16px;
    color: inherit;
    text-decoration: none;
    transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}

.kart:hover, .kart:focus-visible {
    transform: translateY(-4px);
    border-color: var(--vurgu);
    box-shadow: 0 12px 32px rgba(0, 0, 0, .12);
    outline: none;
}

.simge {
    width: 48px;
    height: 48px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: var(--vurgu);
    color: #fff;
    font-size: 1.5rem;
    font-weight: 700;
}

.baslik { font-size: 1.25rem; font-weight: 700; }
.aciklama { color: var(--soluk); }
.git { margin-top: auto; color: var(--vurgu); font-weight: 600; }

footer { text-align: center; padding: 24px 16px; color: var(--soluk); font-size: .9rem; }

@media (prefers-reduced-motion: reduce) {
    .kart { transition: none; }
}