:root {
    --bg: #0f172a;
    --panel: #111827;
    --panel-2: #0b1222;
    --text: #e5e7eb;
    --muted: #94a3b8;
    --accent: #f59e0b;
    --tile: #1f2937;
    --tile-2: #0f172a;
    --tile-open: #111827;
    --tile-border: #1e293b;
    --danger: #ef4444;
    --safe: #22c55e;
}

* {
    box-sizing: border-box;
}

body {
    margin: 0;
    font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
    color: var(--text);
    background: radial-gradient(1200px 700px at 20% 20%, #1f2937, #0b1020 60%, #05070f);
    min-height: 100vh;
    display: grid;
    place-items: center;
    padding: 24px;
}

.app {
    width: min(92vw, 540px);
    background: linear-gradient(160deg, var(--panel), var(--panel-2));
    border: 1px solid #1f2a44;
    border-radius: 18px;
    padding: 20px 20px 16px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.45);
}

.topbar {
    display: grid;
    gap: 12px;
    margin-bottom: 16px;
}

.topbar h1 {
    margin: 0;
    font-size: 28px;
    letter-spacing: 0.5px;
}

.status {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: 10px;
}

.status-item {
    display: grid;
    gap: 2px;
    padding: 8px 12px;
    background: rgba(15, 23, 42, 0.7);
    border: 1px solid #1e293b;
    border-radius: 10px;
    text-align: center;
}

.label {
    font-size: 12px;
    text-transform: uppercase;
    color: var(--muted);
    letter-spacing: 1px;
}

.value {
    font-size: 22px;
    font-weight: 700;
}

.reset {
    width: 42px;
    height: 42px;
    border-radius: 12px;
    border: 1px solid #1e293b;
    background: #0f172a;
    font-size: 22px;
    cursor: pointer;
    transition: transform 0.1s ease, background 0.2s ease;
}

.reset:active {
    transform: scale(0.96);
}

.board-wrap {
    display: grid;
    place-items: center;
    padding: 10px 4px 8px;
}

.board {
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    gap: 6px;
    width: 100%;
    max-width: 420px;
}

.tile {
    aspect-ratio: 1;
    border-radius: 8px;
    border: 1px solid var(--tile-border);
    background: linear-gradient(160deg, var(--tile), var(--tile-2));
    color: var(--text);
    font-size: 18px;
    font-weight: 700;
    display: grid;
    place-items: center;
    cursor: pointer;
    user-select: none;
    transition: background 0.12s ease, transform 0.1s ease;
}

.tile:active {
    transform: translateY(1px);
}

.tile.open {
    background: var(--tile-open);
    cursor: default;
}

.tile.mine {
    background: rgba(239, 68, 68, 0.2);
    border-color: rgba(239, 68, 68, 0.5);
}

.tile.flagged {
    color: var(--accent);
}

.help {
    margin-top: 12px;
    display: flex;
    justify-content: space-between;
    color: var(--muted);
    font-size: 12px;
}

@media (max-width: 480px) {
    .app {
        padding: 16px;
    }

    .board {
        gap: 4px;
    }
}