:root {
    color-scheme: light;
    --bg: #eef2f7;
    --panel: #ffffff;
    --border: #e3e5e8;
    --text: #1f2430;
    --muted: #5b6472;
    --accent: #2563eb;
    --glow-1: rgba(37, 99, 235, 0.08);
    --glow-2: rgba(139, 92, 246, 0.06);
}
:root[data-theme="dark"] {
    color-scheme: dark;
    --bg: #0b1220;
    --panel: rgba(148, 163, 184, 0.08);
    --border: rgba(148, 163, 184, 0.22);
    --text: #e2e8f0;
    --muted: #94a3b8;
    --accent: #38bdf8;
    --glow-1: rgba(56, 189, 248, 0.16);
    --glow-2: rgba(167, 139, 250, 0.14);
}
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        color-scheme: dark;
        --bg: #0b1220;
        --panel: rgba(148, 163, 184, 0.08);
        --border: rgba(148, 163, 184, 0.22);
        --text: #e2e8f0;
        --muted: #94a3b8;
        --accent: #38bdf8;
        --glow-1: rgba(56, 189, 248, 0.16);
        --glow-2: rgba(167, 139, 250, 0.14);
    }
}

* { box-sizing: border-box; }

body {
    margin: 0;
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 32px;
    background:
        radial-gradient(circle at 15% 10%, var(--glow-1), transparent 45%),
        radial-gradient(circle at 85% 90%, var(--glow-2), transparent 45%),
        var(--bg);
    color: var(--text);
    font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
}

main {
    width: min(760px, 100%);
    padding: 40px;
    border: 1px solid var(--border);
    border-radius: 20px;
    background: var(--panel);
    backdrop-filter: blur(14px);
}

.mark {
    font-size: 42px;
    color: var(--accent);
}

h1 {
    margin: 8px 0 10px;
    font-size: clamp(28px, 5vw, 42px);
    letter-spacing: -0.03em;
}

.lead {
    margin: 0 0 28px;
    color: var(--muted);
    line-height: 1.6;
}

.clock {
    font-size: clamp(34px, 7vw, 58px);
    font-weight: 700;
    font-variant-numeric: tabular-nums;
    letter-spacing: 0.02em;
    color: var(--accent);
    margin-bottom: 32px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
    gap: 14px;
}

section {
    padding: 16px;
    border: 1px solid var(--border);
    border-radius: 12px;
}

h2 {
    margin: 0 0 8px;
    font-size: 11px;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--muted);
}

section p {
    margin: 0;
    font-size: 13px;
    line-height: 1.55;
    color: var(--text);
}

code {
    font-size: 12px;
    color: var(--accent);
}

footer {
    margin-top: 28px;
    font-size: 12px;
    color: var(--muted);
}