body {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.game-container {
    text-align: center;
    max-width: 780px;
}

.game-area {
    background: #fffaf0;
    padding: 26px;
    border-radius: 12px;
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.14);
}

h1 {
    color: var(--primary-color);
    margin: 0;
}

.status {
    font-size: 1.18rem;
    margin-bottom: 14px;
    font-weight: 800;
    color: #3a2414;
    min-height: 1.6em;
}

.xiangqi-board-wrapper {
    --cell-size: clamp(34px, 8.4vw, 58px);
    display: inline-block;
    position: relative;
    margin: 0 auto;
    padding-left: 20px;
}

.xiangqi-rank-labels {
    position: absolute;
    left: 0;
    top: 0;
    display: flex;
    flex-direction: column;
    height: calc(var(--cell-size) * 10);
}

.xiangqi-rank-labels .label {
    width: 16px;
    height: var(--cell-size);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.72rem;
    color: #7a6048;
    font-weight: 700;
}

.xiangqi-file-labels {
    display: grid;
    grid-template-columns: repeat(9, var(--cell-size));
    margin-left: 0;
}

.xiangqi-file-labels .label {
    text-align: center;
    font-size: 0.72rem;
    color: #7a6048;
    font-weight: 700;
    padding-top: 3px;
}

.xiangqi-board {
    --line-color: rgba(93, 58, 26, 0.72);
    position: relative;
    display: grid;
    grid-template-columns: repeat(9, var(--cell-size));
    grid-template-rows: repeat(10, var(--cell-size));
    width: calc(var(--cell-size) * 9);
    height: calc(var(--cell-size) * 10);
    border: 4px solid #6b3f1f;
    border-radius: 8px;
    overflow: hidden;
    background:
        linear-gradient(var(--line-color), var(--line-color)) left calc(var(--cell-size) / 2) top calc(var(--cell-size) / 2) / calc(var(--cell-size) * 8) 1px repeat-y,
        linear-gradient(90deg, var(--line-color), var(--line-color)) left calc(var(--cell-size) / 2) top calc(var(--cell-size) / 2) / 1px calc(var(--cell-size) * 9) repeat-x,
        linear-gradient(180deg, #f3c982 0%, #f0c071 49%, #e5ac58 50%, #f3c982 100%);
    box-shadow: 0 6px 18px rgba(65, 37, 15, 0.3);
}

.xiangqi-board::after {
    content: '楚河        漢界';
    position: absolute;
    left: 0;
    right: 0;
    top: calc(var(--cell-size) * 4.48);
    height: calc(var(--cell-size) * 1.05);
    display: flex;
    align-items: center;
    justify-content: center;
    white-space: pre;
    color: rgba(102, 53, 20, 0.44);
    font-size: clamp(1rem, 3.8vw, 1.7rem);
    font-weight: 900;
    letter-spacing: 0.12em;
    pointer-events: none;
    z-index: 1;
}

.xiangqi-cell {
    width: var(--cell-size);
    height: var(--cell-size);
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    user-select: none;
    cursor: default;
    z-index: 2;
}

.xiangqi-cell.palace {
    background: rgba(255, 255, 255, 0.12);
}

.xiangqi-cell.river-edge-red {
    border-top: 2px solid rgba(107, 63, 31, 0.45);
}

.xiangqi-cell.river-edge-black {
    border-bottom: 2px solid rgba(107, 63, 31, 0.45);
}

.xiangqi-cell.selected {
    background: rgba(255, 224, 102, 0.46);
    box-shadow: inset 0 0 0 3px #f1c40f;
}

.xiangqi-cell.last-move {
    background: rgba(255, 245, 136, 0.38);
}

.xiangqi-cell.in-check {
    background: radial-gradient(circle, rgba(231, 76, 60, 0.55), rgba(231, 76, 60, 0.18) 48%, transparent 72%);
}

.xiangqi-cell.has-piece {
    cursor: pointer;
}

.xiangqi-cell.has-piece:hover .xiangqi-piece {
    transform: translateY(-1px) scale(1.04);
}

.xiangqi-cell.valid-move,
.xiangqi-cell.valid-capture {
    cursor: pointer;
}

.xiangqi-cell.valid-move::before {
    content: '';
    width: 15px;
    height: 15px;
    border-radius: 50%;
    background: rgba(46, 204, 113, 0.72);
    box-shadow: 0 0 0 3px rgba(46, 204, 113, 0.2);
    z-index: 4;
}

.xiangqi-cell.valid-capture::before {
    content: '';
    position: absolute;
    width: calc(var(--cell-size) - 10px);
    height: calc(var(--cell-size) - 10px);
    border-radius: 50%;
    border: 3px solid rgba(231, 76, 60, 0.82);
    z-index: 4;
    pointer-events: none;
}

.xiangqi-piece {
    width: calc(var(--cell-size) - 8px);
    height: calc(var(--cell-size) - 8px);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: "Noto Serif CJK SC", "Microsoft YaHei", "SimSun", Georgia, serif;
    font-size: clamp(1.28rem, 5.5vw, 2.25rem);
    font-weight: 900;
    line-height: 1;
    background: radial-gradient(circle at 35% 28%, #fff7df, #e6bc78 66%, #b97933 100%);
    border: 3px solid #8b4a1e;
    box-shadow: 0 3px 7px rgba(0, 0, 0, 0.25), inset 0 1px 1px rgba(255, 255, 255, 0.75);
    transition: transform 0.12s ease;
    z-index: 3;
}

.xiangqi-piece.red-piece {
    color: #c0392b;
    border-color: #b33025;
}

.xiangqi-piece.black-piece {
    color: #1d1d1f;
    border-color: #262626;
}

.captured-section {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    margin: 8px 0;
    min-height: 28px;
    flex-wrap: wrap;
}

.captured-label {
    font-size: 0.86rem;
    color: #73543a;
    font-weight: 700;
}

.captured-pieces {
    display: inline-flex;
    gap: 3px;
    flex-wrap: wrap;
    font-size: 1.1rem;
}

.move-history {
    margin: 15px auto 0;
    border: 1px solid rgba(107, 63, 31, 0.24);
    border-radius: 8px;
    overflow: hidden;
    text-align: left;
    max-width: 560px;
    background: #fffdf8;
}

.move-history-header {
    background: #f4e0bc;
    padding: 8px 12px;
    font-weight: 800;
    font-size: 0.86rem;
    color: #5b351b;
    border-bottom: 1px solid rgba(107, 63, 31, 0.18);
}

.move-list {
    max-height: 150px;
    overflow-y: auto;
    padding: 8px 12px;
    font-family: "Consolas", "Courier New", monospace;
    font-size: 0.84rem;
}

.move-row {
    display: grid;
    grid-template-columns: 38px 1fr 1fr;
    gap: 10px;
    padding: 2px 0;
}

.move-number {
    color: #9b7a55;
    text-align: right;
}

.move-red {
    color: #b33025;
    font-weight: 700;
}

.move-black {
    color: #222;
    font-weight: 700;
}

.ai-difficulty {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-bottom: 10px;
}

.difficulty-label {
    font-size: 0.9rem;
    font-weight: 700;
    color: #5b351b;
}

.difficulty-toggle {
    display: flex;
    border-radius: 20px;
    overflow: hidden;
    border: 2px solid #9b7a55;
}

.diff-btn {
    padding: 5px 16px;
    border: none;
    background: #fff3d6;
    cursor: pointer;
    font-size: 0.86rem;
    font-weight: 800;
    color: #5b351b;
    transition: background 0.15s, color 0.15s;
}

.diff-btn.active {
    background: #7b3f1d;
    color: #fff;
}

.diff-btn:hover:not(.active) {
    background: #f1d29b;
}

.game-buttons {
    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 20px;
}

#exit-game-btn {
    padding: 10px 20px;
    font-size: 1rem;
}

.online-info {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-bottom: 15px;
}

.opponent-name {
    font-weight: 700;
    color: var(--text-muted, #666);
}

@media (max-width: 540px) {
    .game-container {
        max-width: 100%;
    }

    .game-area {
        padding: 14px 8px;
    }

    .xiangqi-board-wrapper {
        --cell-size: clamp(32px, 9.4vw, 42px);
        padding-left: 16px;
    }

    .xiangqi-board {
        border-width: 3px;
    }

    .xiangqi-piece {
        border-width: 2px;
    }

    .xiangqi-cell.valid-move::before {
        width: 12px;
        height: 12px;
    }

    .move-list {
        font-size: 0.76rem;
    }
}