:root {
    color-scheme: light dark;
    --bg: #ffffff;
    --fg: #1a1a1a;
    --muted: #666666;
    --link: #0b5fa5;
    --rule: #e0e0e0;
    --code-bg: #f4f4f4;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #1c1c1c;
        --fg: #e8e8e8;
        --muted: #a0a0a0;
        --link: #79b8ff;
        --rule: #3a3a3a;
        --code-bg: #262626;
    }
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    background: var(--bg);
    color: var(--fg);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    font-size: 1rem;
    line-height: 1.6;
}

main {
    max-width: 750px;
    margin: 0 auto;
    padding: 3rem 1rem;
}

/* Vertically centered card layout (index only). `margin: auto` on the child
   keeps overflow scrollable instead of clipping the top on short viewports. */
body.card {
    display: flex;
    min-height: 100vh;
}

body.card main {
    margin: auto;
    width: 100%;
}

h1,
h2,
h3 {
    line-height: 1.25;
    margin-top: 2rem;
}

h1 {
    margin-top: 0;
}

a {
    color: var(--link);
}

hr {
    border: none;
    border-top: 1px solid var(--rule);
    margin: 2rem 0;
}

img {
    max-width: 100%;
}

code {
    background: var(--code-bg);
    padding: 0.1em 0.3em;
    border-radius: 3px;
    font-size: 0.9em;
}

pre {
    background: var(--code-bg);
    padding: 1rem;
    border-radius: 4px;
    overflow-x: auto;
}

pre code {
    background: none;
    padding: 0;
}

.social-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    justify-content: space-between;
    margin: 2rem 0;
}

.social-links a {
    display: block;
    line-height: 0;
}

nav.back {
    margin-bottom: 2rem;
    font-size: 0.9rem;
}

footer {
    margin-top: 3rem;
    padding-top: 1rem;
    border-top: 1px solid var(--rule);
    color: var(--muted);
    font-size: 0.9rem;
}