:root {
    --bg-0: #050506;
    --bg-1: #111317;
    --bg-2: #1d222b;
    --text-main: #edf2f9;
    --text-muted: #aeb8c8;
    --accent: #88ff00;
    --panel: rgba(13, 18, 25, 0.72);
    --panel-stroke: rgba(255, 255, 255, 0.16);
}

html,
body {
    margin: 0;
    min-height: 100%;
    font-family: "Trebuchet MS", "Segoe UI", Arial, sans-serif;
    color: var(--text-main);
    background:
        radial-gradient(1200px 700px at 10% 5%, #1f242f 0%, transparent 55%),
        radial-gradient(900px 600px at 85% 90%, #20262f 0%, transparent 55%),
        linear-gradient(170deg, var(--bg-0) 0%, var(--bg-1) 45%, var(--bg-2) 100%);
}

.topbar {
    display: flex;
    gap: 0.8rem;
    padding: 1rem 1.25rem;
    flex-wrap: wrap;
}

.topbar-link {
    color: var(--text-main);
    text-decoration: none;
    padding: 0.55rem 1rem;
    border-radius: 999px;
    border: 1px solid rgba(255, 255, 255, 0.18);
    background: rgba(255, 255, 255, 0.05);
    transition: border-color 0.2s ease, background-color 0.2s ease, transform 0.2s ease;
}

.topbar-link:hover {
    transform: translateY(-1px);
    border-color: rgba(136, 255, 0, 0.55);
    background: rgba(136, 255, 0, 0.12);
}

.board-shell {
    padding: 0.75rem 1rem 1.5rem 1rem;
}

.board-card {
    width: min(720px, 100%);
    margin: 0 auto;
    padding: 1.1rem;
    border-radius: 16px;
    border: 1px solid var(--panel-stroke);
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.02), rgba(255, 255, 255, 0)),
        var(--panel);
    box-shadow: 0 16px 35px rgba(0, 0, 0, 0.32);
}

.board-card h1 {
    margin: 0;
}

.subhead {
    margin-top: 0.35rem;
    color: var(--text-muted);
}

.mode-row {
    display: flex;
    gap: 0.6rem;
    flex-wrap: wrap;
    margin-top: 0.75rem;
    margin-bottom: 0.25rem;
}

.mode-btn {
    border: 1px solid rgba(255, 255, 255, 0.22);
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-main);
    border-radius: 999px;
    padding: 0.45rem 0.9rem;
    cursor: pointer;
}

.mode-btn.active {
    border-color: rgba(136, 255, 0, 0.75);
    background: rgba(136, 255, 0, 0.14);
}

.status {
    margin: 0.75rem 0 0.3rem 0;
    color: #c8d7ec;
    font-size: 0.9rem;
}

.leaderboard-head {
    margin-top: 0.8rem;
    display: grid;
    grid-template-columns: 56px 1fr 76px 88px;
    gap: 0.6rem;
    font-size: 0.74rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #9fb2cc;
    padding: 0 0.7rem;
}

.leaderboard-list {
    margin: 0;
    padding: 0;
    list-style: none;
    display: grid;
    gap: 0.42rem;
}

.leaderboard-list li {
    color: var(--text-main);
    border: 1px solid rgba(255, 255, 255, 0.12);
    background: rgba(255, 255, 255, 0.04);
    border-radius: 12px;
    padding: 0.58rem 0.7rem;
    display: grid;
    grid-template-columns: 56px 1fr 76px 88px;
    gap: 0.6rem;
    align-items: center;
}

.leaderboard-cell-rank {
    font-weight: 700;
    color: #d5e4fb;
}

.leaderboard-cell-player {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.leaderboard-cell-score {
    font-weight: 700;
    color: var(--accent);
}

.leaderboard-cell-date {
    color: var(--text-muted);
    font-size: 0.82rem;
}

.chart-section {
    margin-top: 1.05rem;
    padding-top: 0.95rem;
    border-top: 1px solid rgba(255, 255, 255, 0.14);
}

.chart-section h2 {
    margin: 0;
    font-size: 1rem;
}

.chart-summary {
    margin: 0.45rem 0 0.6rem 0;
    color: #c8d7ec;
    font-size: 0.88rem;
}

.chart-hook {
    border: 1px dashed rgba(136, 255, 0, 0.45);
    border-radius: 12px;
    padding: 0.75rem 0.8rem;
    color: var(--text-muted);
    font-size: 0.86rem;
    background: rgba(136, 255, 0, 0.05);
    min-height: 52px;
    display: flex;
    align-items: center;
}

@media (max-width: 430px) {
    .board-card {
        padding: 0.8rem;
        border-radius: 14px;
    }

    .board-card h1 {
        font-size: 1.45rem;
    }

    .leaderboard-head,
    .leaderboard-list li {
        grid-template-columns: 48px 1fr 62px 72px;
        gap: 0.42rem;
    }

    .leaderboard-head {
        font-size: 0.66rem;
        padding: 0 0.55rem;
    }

    .leaderboard-list li {
        font-size: 0.87rem;
        padding: 0.5rem 0.55rem;
    }

    .leaderboard-cell-date {
        font-size: 0.74rem;
    }
}