:root {
    color-scheme: dark;

    --bg: #0d1117;
    --surface: #161b22;
    --surface-hover: #1c2128;
    --border: #30363d;

    --text: #e6edf3;
    --text-muted: #8b949e;

    --accent: #58a6ff;
    --accent-hover: #79c0ff;
    --success: #3fb950;

    --radius: 8px;
    --content-width: 1920px;
    --card-width: 520px;
    --gap: 24px;
}

* {
    box-sizing: border-box;
}

html {
    font-family: Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

body {
    margin: 0;
    min-height: 100vh;
    background: var(--bg);
    color: var(--text);
}

header,
main,
footer {
    width: min(calc(100% - 48px), var(--content-width));
    margin-inline: auto;
}

header {
    padding-block: 32px 24px;
}

header h1 {
    margin: 0;
    font-size: 1.5rem;
    font-weight: 600;
}

main {
    padding-block: 24px;
}

.tool-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, var(--card-width)));
    justify-content: center;
    gap: var(--gap);
}

.tool-card {
    width: 100%;
    padding: 24px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
}

.tool-card-header h2 {
    margin: 0 0 8px;
    font-size: 1.15rem;
}

.tool-card-header p {
    margin: 0 0 24px;
    color: var(--text-muted);
}

footer {
    padding-block: 32px;
    color: var(--text-muted);
    font-size: 0.875rem;
}

@media (max-width: 1200px) {
    .tool-grid {
        grid-template-columns: repeat(2, minmax(0, var(--card-width)));
    }
}

@media (max-width: 700px) {
    header,
    main,
    footer {
        width: min(calc(100% - 32px), var(--content-width));
    }

    .tool-grid {
        grid-template-columns: minmax(0, 1fr);
    }
}