@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;600;700&family=DM+Mono:wght@400;500&family=Noto+Sans+SC:wght@400;600;700&display=swap');
@import url(https://fonts.googleapis.com/css?family=Righteous);

:root {
    color-scheme: dark;
    --bg-0: #0c111a;
    --bg-1: #111827;
    --panel: rgba(14, 19, 28, 0.72);
    --panel-strong: rgba(17, 24, 39, 0.88);
    --panel-border: rgba(255, 255, 255, 0.09);
    --text-0: #eef2f6;
    --text-1: rgba(238, 242, 246, 0.74);
    --text-2: rgba(238, 242, 246, 0.52);
    --text-3: rgba(238, 242, 246, 0.38);
    --accent: #38bdf8;
    --accent-2: #a78bfa;
    --accent-3: #f59e0b;
    --good: #34d399;
    --warn: #fbbf24;
    --danger: #fb7185;
    --grid-line: rgba(255, 255, 255, 0.13);
    --input-bg: rgba(255, 255, 255, 0.06);
    --shadow: 0 24px 60px rgba(0, 0, 0, 0.35);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    font-family: 'Space Grotesk', 'Noto Sans SC', sans-serif;
    color: var(--text-0);
    background:
        radial-gradient(circle at 20% 10%, rgba(56, 189, 248, 0.22), transparent 28rem),
        radial-gradient(circle at 80% 18%, rgba(167, 139, 250, 0.18), transparent 26rem),
        radial-gradient(at 50% 0, transparent, #080808),
        repeating-conic-gradient(hsla(0, 0%, 0%, .235) 0% 25%, transparent 0% 50%) 0 0 / 0.375em 0.375em,
        #3b3b3b;
}

body.day-mode,
html.day-init body {
    color: #172033;
    background:
        radial-gradient(circle at 15% 10%, rgba(14, 165, 233, 0.2), transparent 28rem),
        radial-gradient(circle at 80% 14%, rgba(245, 158, 11, 0.18), transparent 24rem),
        linear-gradient(135deg, #f8fafc 0%, #e2e8f0 100%);
    --panel: rgba(255, 255, 255, 0.76);
    --panel-strong: rgba(255, 255, 255, 0.9);
    --panel-border: rgba(15, 23, 42, 0.1);
    --text-0: #172033;
    --text-1: rgba(23, 32, 51, 0.72);
    --text-2: rgba(23, 32, 51, 0.54);
    --text-3: rgba(23, 32, 51, 0.38);
    --grid-line: rgba(15, 23, 42, 0.18);
    --input-bg: rgba(255, 255, 255, 0.78);
    --shadow: 0 24px 60px rgba(15, 23, 42, 0.14);
}

.navbar {
    position: sticky;
    top: 0;
    z-index: 50;
    width: 100%;
    align-self: stretch;
    background-color: rgba(0, 0, 0, 0.4);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(12px) saturate(1.2);
    -webkit-backdrop-filter: blur(12px) saturate(1.2);
}

body.day-mode .navbar,
html.day-init .navbar {
    background-color: rgba(255, 255, 255, 0.62);
    border-bottom-color: rgba(15, 23, 42, 0.1);
}

.nav-content {
    max-width: 80rem;
    margin: 0 auto;
    padding: 0.75rem 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.logo-wrapper {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    flex-shrink: 0;
}

.logo-icon {
    width: 2.25rem;
    height: 2.25rem;
    border-radius: 50%;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.3);
    object-fit: cover;
}

.logo-text-desktop {
    font-family: 'Righteous', 'Microsoft YaHei', sans-serif;
    font-size: 1.125rem;
    font-weight: 900;
    color: hsl(0 0% 95%);
    letter-spacing: 0.05em;
}

body.day-mode .logo-text-desktop,
html.day-init .logo-text-desktop {
    color: #172033;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex: 1;
    justify-content: flex-end;
}

.nav-btn {
    -webkit-tap-highlight-color: #0000;
    cursor: pointer;
    border-radius: 12px;
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    background: #0000;
    border: 1px solid #0000;
    position: relative;
    color: white;
    transition: translate 0.1s ease-out, scale 0.1s ease-out;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    justify-content: center;
    text-decoration: none;
}

body.day-mode .nav-btn,
html.day-init .nav-btn {
    color: #172033;
}

.nav-btn::before,
.nav-btn::after {
    content: '';
    position: absolute;
    inset: -1px;
    border-radius: inherit;
    pointer-events: none;
}

.nav-btn::before {
    z-index: -1;
    background: linear-gradient(hsl(0 0% 100% / 0.18), hsl(0 0% 4% / 0.7));
    backdrop-filter: saturate(2) contrast(1) blur(10px);
}

body.day-mode .nav-btn::before,
html.day-init .nav-btn::before {
    background: linear-gradient(hsl(0 0% 100% / 0.92), hsl(210 40% 90% / 0.72));
}

.nav-btn::after {
    box-shadow: 0 0 1px 0.8px hsl(0 0% 100% / 0.8) inset;
    mask: linear-gradient(-35deg, #ffffff80, #ffffff30 30% 60%, #fff);
}

.nav-btn:hover:not(:disabled) {
    scale: 1.02;
}

.nav-btn:active:not(:disabled) {
    scale: 0.98;
    translate: 0 1px;
}

.page-container {
    width: 100%;
    max-width: 92rem;
    flex: 1;
    padding: 20px 1rem 32px;
}

.header {
    text-align: center;
    margin-bottom: 2rem;
    display: grid;
    gap: 0.4rem;
    justify-items: center;
}

.eyebrow {
    text-transform: uppercase;
    letter-spacing: 0.18em;
    font-size: 0.75rem;
    color: var(--text-2);
}

.header h1 {
    display: inline-block;
    color: hsl(0 0% 90%);
    font-family: 'Righteous', 'Microsoft YaHei', serif;
    font-size: clamp(2.6rem, 7vw, 4.8rem);
    text-shadow: .03em .03em 0 hsla(230, 40%, 50%, 1);
    position: relative;
    line-height: 1.1;
    margin-bottom: 0.3rem;
}

body.day-mode .header h1,
html.day-init .header h1 {
    color: #172033;
    text-shadow: .03em .03em 0 rgba(56, 189, 248, 0.34);
}

.header h1::after {
    content: attr(data-shadow);
    position: absolute;
    top: .06em;
    left: .06em;
    width: 100%;
    z-index: -1;
    color: transparent;
    text-shadow: none;
    background-image: linear-gradient(45deg, transparent 45%, hsla(48, 20%, 90%, 1) 45%, hsla(48, 20%, 90%, 1) 55%, transparent 0);
    background-size: .05em .05em;
    -webkit-background-clip: text;
    background-clip: text;
}

.subtitle,
.panel-subtitle {
    color: var(--text-1);
    line-height: 1.7;
}

.game-shell {
    display: grid;
    grid-template-columns: minmax(240px, 0.72fr) minmax(360px, 1.6fr) minmax(260px, 0.82fr);
    gap: 1rem;
    align-items: start;
}

.panel {
    background: var(--panel);
    border: 1px solid var(--panel-border);
    border-radius: 24px;
    box-shadow: var(--shadow);
    backdrop-filter: blur(18px) saturate(1.15);
    -webkit-backdrop-filter: blur(18px) saturate(1.15);
    overflow: hidden;
}

.panel-head {
    padding: 1.25rem;
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    align-items: flex-start;
    border-bottom: 1px solid var(--panel-border);
}

.panel-head.compact {
    padding-bottom: 1rem;
}

.panel-head h2 {
    font-size: 1.35rem;
    line-height: 1.25;
    margin-top: 0.3rem;
}

.board-head {
    align-items: center;
}

.board-toolbar {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    justify-content: flex-end;
}

.btn {
    border: 1px solid rgba(255, 255, 255, 0.16);
    color: var(--text-0);
    border-radius: 12px;
    padding: 0.66rem 1rem;
    background: rgba(255, 255, 255, 0.08);
    cursor: pointer;
    font-weight: 700;
    font-family: inherit;
    transition: transform 0.16s ease, border-color 0.16s ease, background 0.16s ease, opacity 0.16s ease;
}

.btn:hover:not(:disabled) {
    transform: translateY(-1px);
    border-color: rgba(56, 189, 248, 0.5);
}

.btn:disabled {
    cursor: not-allowed;
    opacity: 0.45;
}

.btn-primary {
    background: linear-gradient(135deg, rgba(56, 189, 248, 0.86), rgba(167, 139, 250, 0.82));
    color: #ffffff;
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.08);
}

body.day-mode .btn-secondary {
    background: rgba(255, 255, 255, 0.82);
    border-color: rgba(15, 23, 42, 0.12);
}

.game-list {
    padding: 1rem;
    display: grid;
    gap: 0.8rem;
}

.game-card {
    border: 1px solid var(--panel-border);
    background: rgba(255, 255, 255, 0.035);
    color: var(--text-0);
    border-radius: 14px;
    padding: 0.85rem 0.95rem;
    display: grid;
    gap: 0.35rem;
    text-align: left;
    cursor: pointer;
    font-family: inherit;
    transition: transform 0.18s ease, border-color 0.18s ease, background 0.18s ease;
}

body.day-mode .game-card {
    background: rgba(255, 255, 255, 0.74);
}

.game-card:hover,
.game-card.is-active {
    transform: none;
    border-color: color-mix(in srgb, var(--game-color), white 20%);
    background: color-mix(in srgb, var(--game-color), transparent 86%);
}

.game-card h3 {
    font-size: 1rem;
}

.game-card p {
    color: var(--text-1);
    line-height: 1.45;
    font-size: 0.86rem;
}

.mini-badge {
    font-size: 0.75rem;
    color: var(--text-1);
    border: 1px solid var(--panel-border);
    background: rgba(255, 255, 255, 0.06);
    border-radius: 999px;
    padding: 0.22rem 0.55rem;
}

.move-section h3 {
    font-size: 1rem;
    margin-bottom: 0.5rem;
}

.status-grid {
    padding: 1rem 1.25rem 0;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 0.75rem;
}

.status-card {
    padding: 0.8rem;
    border-radius: 16px;
    background: rgba(255, 255, 255, 0.055);
    border: 1px solid var(--panel-border);
    display: grid;
    gap: 0.3rem;
}

body.day-mode .status-card {
    background: rgba(255, 255, 255, 0.72);
}

.status-card span {
    color: var(--text-2);
    font-size: 0.78rem;
}

.status-card strong {
    font-size: 1.02rem;
    line-height: 1.35;
}

.board-wrap {
    margin: 1.25rem;
    min-height: 31rem;
    border-radius: 26px;
    display: grid;
    place-items: center;
    padding: 1rem;
    background:
        radial-gradient(circle at center, rgba(56, 189, 248, 0.12), transparent 27rem),
        rgba(0, 0, 0, 0.18);
    border: 1px solid var(--panel-border);
    overflow: auto;
}

body.day-mode .board-wrap {
    background:
        radial-gradient(circle at center, rgba(14, 165, 233, 0.1), transparent 27rem),
        rgba(248, 250, 252, 0.68);
}

.board {
    --cols: 15;
    --rows: 15;
    --gap: 4px;
    --cell-size: 38px;
    display: grid;
    grid-template-columns: repeat(var(--cols), var(--cell-size));
    gap: var(--gap);
    padding: clamp(0.5rem, 2vw, 1rem);
    border-radius: 22px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--panel-border);
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.04), 0 16px 40px rgba(0, 0, 0, 0.25);
}

.board.gomoku {
    --gap: 1px;
    --cell-size: clamp(21px, 4.5vw, 38px);
    padding: clamp(0.65rem, 2vw, 1rem);
    background:
        linear-gradient(rgba(218, 178, 123, 0.2), rgba(218, 178, 123, 0.2)),
        url('../img/bg.jpg');
    background-size: cover;
    background-position: center;
    border: 1px solid rgba(73, 42, 17, 0.72);
    box-shadow:
        inset 0 0 0 4px rgba(95, 55, 21, 0.18),
        inset 0 0 22px rgba(74, 41, 15, 0.22),
        0 18px 42px rgba(0, 0, 0, 0.28);
}

.board.reversi {
    --gap: 5px;
    --cell-size: clamp(34px, 7.2vw, 58px);
    background: linear-gradient(135deg, #064e3b, #052e2b);
    border-color: rgba(52, 211, 153, 0.25);
}

.board.tictactoe {
    --gap: 10px;
    --cell-size: clamp(78px, 22vw, 124px);
    background: linear-gradient(135deg, rgba(56, 189, 248, 0.22), rgba(167, 139, 250, 0.2));
}

.cell {
    width: var(--cell-size);
    height: var(--cell-size);
    border: 0;
    border-radius: 12px;
    display: grid;
    place-items: center;
    font-family: inherit;
    color: var(--text-0);
    cursor: pointer;
    position: relative;
    background: rgba(255, 255, 255, 0.06);
    transition: transform 0.12s ease, box-shadow 0.12s ease, background 0.12s ease;
}

.cell:disabled {
    cursor: default;
}

.cell.legal:not(.occupied):hover {
    transform: translateY(-1px);
    box-shadow: 0 0 0 2px rgba(56, 189, 248, 0.44), 0 10px 20px rgba(0, 0, 0, 0.18);
}

.cell.hint::after {
    content: '';
    position: absolute;
    inset: 16%;
    border-radius: 50%;
    border: 2px solid var(--warn);
    box-shadow: 0 0 16px rgba(251, 191, 36, 0.72);
    pointer-events: none;
}

.cell.win {
    box-shadow: inset 0 0 0 3px rgba(251, 191, 36, 0.86), 0 0 18px rgba(251, 191, 36, 0.38);
}

.board.gomoku .cell {
    border-radius: 0;
    background:
        linear-gradient(90deg, transparent calc(50% - 0.5px), rgba(0, 0, 0, 0.68) 50%, transparent calc(50% + 0.5px)),
        linear-gradient(0deg, transparent calc(50% - 0.5px), rgba(0, 0, 0, 0.68) 50%, transparent calc(50% + 0.5px));
}

.board.gomoku .cell.legal:not(.occupied)::after {
    content: '';
    width: 20%;
    height: 20%;
    border-radius: 50%;
    background: rgba(80, 44, 18, 0.24);
}

.board.reversi .cell {
    border-radius: 10px;
    background: linear-gradient(135deg, #047857, #065f46);
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.08);
}

.board.reversi .cell.legal:not(.occupied)::after {
    content: attr(data-flips);
    width: 1.35rem;
    height: 1.35rem;
    border-radius: 50%;
    display: grid;
    place-items: center;
    background: rgba(255, 255, 255, 0.18);
    color: rgba(255, 255, 255, 0.78);
    font-size: 0.75rem;
    font-weight: 700;
}

.board.tictactoe .cell {
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid var(--panel-border);
}

.piece {
    width: 72%;
    height: 72%;
    border-radius: 50%;
    display: grid;
    place-items: center;
    font-weight: 900;
    line-height: 1;
}

.piece.black {
    background: radial-gradient(circle at 35% 28%, #52525b, #020617 68%);
    box-shadow: inset 0 0 10px rgba(255, 255, 255, 0.12), 0 6px 12px rgba(0, 0, 0, 0.32);
}

.piece.white {
    background: radial-gradient(circle at 35% 28%, #ffffff, #cbd5e1 72%);
    box-shadow: inset 0 0 10px rgba(15, 23, 42, 0.12), 0 6px 12px rgba(0, 0, 0, 0.24);
}


.board.reversi .piece.reversi-flip {
    transform-origin: center;
    transform-style: preserve-3d;
    will-change: transform, background, box-shadow;
}

.board.reversi .piece.reversi-flip.from-black.to-white {
    animation: reversi-flip-black-to-white 0.64s cubic-bezier(0.2, 0.72, 0.18, 1.08);
}

.board.reversi .piece.reversi-flip.from-white.to-black {
    animation: reversi-flip-white-to-black 0.64s cubic-bezier(0.2, 0.72, 0.18, 1.08);
}

@keyframes reversi-flip-black-to-white {
    0% {
        transform: rotateY(0deg) scale(1);
        background: radial-gradient(circle at 35% 28%, #52525b, #020617 68%);
        box-shadow: inset 0 0 10px rgba(255, 255, 255, 0.12), 0 6px 12px rgba(0, 0, 0, 0.32);
    }
    48% {
        transform: rotateY(88deg) scale(0.96);
        background: radial-gradient(circle at 35% 28%, #52525b, #020617 68%);
        box-shadow: inset 0 0 10px rgba(255, 255, 255, 0.12), 0 8px 18px rgba(0, 0, 0, 0.36);
    }
    52% {
        transform: rotateY(92deg) scale(0.96);
        background: radial-gradient(circle at 35% 28%, #ffffff, #cbd5e1 72%);
        box-shadow: inset 0 0 10px rgba(15, 23, 42, 0.12), 0 8px 18px rgba(0, 0, 0, 0.24);
    }
    100% {
        transform: rotateY(0deg) scale(1);
        background: radial-gradient(circle at 35% 28%, #ffffff, #cbd5e1 72%);
        box-shadow: inset 0 0 10px rgba(15, 23, 42, 0.12), 0 6px 12px rgba(0, 0, 0, 0.24);
    }
}

@keyframes reversi-flip-white-to-black {
    0% {
        transform: rotateY(0deg) scale(1);
        background: radial-gradient(circle at 35% 28%, #ffffff, #cbd5e1 72%);
        box-shadow: inset 0 0 10px rgba(15, 23, 42, 0.12), 0 6px 12px rgba(0, 0, 0, 0.24);
    }
    48% {
        transform: rotateY(88deg) scale(0.96);
        background: radial-gradient(circle at 35% 28%, #ffffff, #cbd5e1 72%);
        box-shadow: inset 0 0 10px rgba(15, 23, 42, 0.12), 0 8px 18px rgba(0, 0, 0, 0.24);
    }
    52% {
        transform: rotateY(92deg) scale(0.96);
        background: radial-gradient(circle at 35% 28%, #52525b, #020617 68%);
        box-shadow: inset 0 0 10px rgba(255, 255, 255, 0.12), 0 8px 18px rgba(0, 0, 0, 0.36);
    }
    100% {
        transform: rotateY(0deg) scale(1);
        background: radial-gradient(circle at 35% 28%, #52525b, #020617 68%);
        box-shadow: inset 0 0 10px rgba(255, 255, 255, 0.12), 0 6px 12px rgba(0, 0, 0, 0.32);
    }
}

.piece.x,
.piece.o {
    width: 100%;
    height: 100%;
    border-radius: 0;
    background: transparent;
    font-size: clamp(2.6rem, 12vw, 4.7rem);
}

.piece.x {
    color: #38bdf8;
    text-shadow: 0 0 18px rgba(56, 189, 248, 0.46);
}

.piece.o {
    color: #f472b6;
    text-shadow: 0 0 18px rgba(244, 114, 182, 0.42);
}

.hint-box {
    margin: 0 1.25rem 1.25rem;
    border-radius: 16px;
    padding: 0.9rem 1rem;
    color: var(--text-1);
    line-height: 1.65;
    background: rgba(56, 189, 248, 0.09);
    border: 1px solid rgba(56, 189, 248, 0.18);
}

.meta-list,
.analysis-panel,
.move-section {
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--panel-border);
}

.move-section {
    border-bottom: 0;
}

.meta-list {
    display: grid;
    gap: 0.75rem;
}

.meta-item {
    display: grid;
    grid-template-columns: minmax(6rem, 0.28fr) 1fr;
    align-items: start;
    gap: 0.9rem 1.25rem;
    color: var(--text-1);
    border-bottom: 1px dashed var(--panel-border);
    padding: 0.85rem 0 1rem;
}

.meta-item:last-child {
    border-bottom: 0;
    padding-bottom: 0.25rem;
}

.meta-item span {
    color: var(--text-2);
    font-size: 0.86rem;
    line-height: 1.55;
}

.meta-item strong {
    color: var(--text-0);
    text-align: left;
    line-height: 1.65;
    font-weight: 600;
}

.analysis-panel {
    display: grid;
    gap: 0.65rem;
}

.analysis-row {
    display: grid;
    gap: 0.35rem;
}

.analysis-row header {
    display: flex;
    justify-content: space-between;
    color: var(--text-1);
    font-size: 0.88rem;
}

.bar {
    height: 0.56rem;
    border-radius: 999px;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.08);
}

.bar span {
    display: block;
    height: 100%;
    border-radius: inherit;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

.section-title-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    margin-bottom: 0.65rem;
}

.move-log {
    height: clamp(12rem, 24vw, 18rem);
    overflow-y: auto;
    overflow-x: hidden;
    display: grid;
    gap: 0.45rem;
    align-content: start;
    padding: 0.75rem 0.9rem 0.75rem 2rem;
    color: var(--text-1);
    border: 1px solid var(--panel-border);
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.035);
    scrollbar-width: thin;
    scrollbar-color: rgba(255, 255, 255, 0.28) transparent;
}

.move-log li {
    line-height: 1.55;
    padding-right: 0.35rem;
}

.move-log::-webkit-scrollbar {
    width: 8px;
}

.move-log::-webkit-scrollbar-track {
    background: transparent;
}

.move-log::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.22);
    border-radius: 999px;
}

body.day-mode .move-log {
    background: rgba(255, 255, 255, 0.5);
    scrollbar-color: rgba(0, 0, 0, 0.22) transparent;
}

body.day-mode .move-log::-webkit-scrollbar-thumb {
    background: rgba(0, 0, 0, 0.18);
}

.footer {
    width: 100%;
    padding: 1.5rem 1rem 2rem;
    text-align: center;
    color: var(--text-2);
    display: grid;
    gap: 0.25rem;
}

@media (max-width: 1180px) {
    .game-shell {
        grid-template-columns: 1fr 1.4fr;
    }

    .control-panel {
        grid-column: 1 / -1;
    }

    .status-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 820px) {
    .nav-content,
    .nav-actions,
    .board-head {
        align-items: stretch;
    }

    .nav-content {
        flex-direction: column;
    }

    .nav-actions,
    .board-toolbar {
        width: 100%;
        justify-content: center;
        flex-wrap: wrap;
        gap: 0.6rem;
    }

    .game-shell {
        grid-template-columns: 1fr;
    }

    .panel-head,
    .board-head {
        flex-direction: column;
    }

    .board-wrap {
        min-height: 22rem;
        margin: 1rem;
        padding: 0.6rem;
    }

    .status-grid {
        grid-template-columns: 1fr 1fr;
        padding: 1rem 1rem 0;
    }

    .hint-box {
        margin: 0 1rem 1rem;
    }

}

@media (max-width: 520px) {
    .page-container {
        padding-inline: 0.65rem;
    }

    .status-grid {
        grid-template-columns: 1fr;
    }

    .board {
        padding: 0.45rem;
    }

    .board.gomoku {
        --cell-size: min(5.5vw, 28px);
    }

    .board.reversi {
        --cell-size: min(10vw, 46px);
        --gap: 3px;
    }

    .board.tictactoe {
        --cell-size: min(26vw, 104px);
        --gap: 7px;
    }
}

:root {
    --bg-dark: #080808;
    --bg-panel: #3b3b3b;
    --accent-color: hsl(122, 40%, 60%);
    --accent-highlight: hsl(122, 40%, 75%);
    --text-primary: hsl(0, 0%, 95%);
    --text-secondary: hsl(0, 0%, 85%);
    --text-muted: hsl(0, 0%, 70%);
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.1);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    --radius-lg: 16px;
    --radius-md: 12px;
    --radius-sm: 8px;
    --input-bg: rgba(255, 255, 255, 0.05);
    --input-focus-bg: rgba(255, 255, 255, 0.08);
    --input-border: rgba(255, 255, 255, 0.15);
    --text-0: var(--text-primary);
    --text-1: var(--text-secondary);
    --text-2: var(--text-muted);
    --panel: var(--glass-bg);
    --panel-border: var(--glass-border);
    --shadow: var(--glass-shadow);
    --accent: var(--accent-color);
    --accent-2: var(--accent-highlight);
    --warn: var(--accent-highlight);
}

body {
    font-family: 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background:
        radial-gradient(at 50% 0, transparent, var(--bg-dark)),
        repeating-conic-gradient(
            hsla(0, 0%, 0%, .235) 0% 25%,
            transparent 0% 50%
        ) 0 0 / 0.375em 0.375em,
        var(--bg-panel);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    color: var(--text-primary);
}

body.day-mode,
html.day-init body {
    --bg-dark: #f0f4f8;
    --bg-panel: #e2e8f0;
    --text-primary: #2d3748;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(0, 0, 0, 0.1);
    --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.05);
    --input-bg: rgba(255, 255, 255, 0.8);
    --input-border: rgba(0, 0, 0, 0.15);
}

body.day-mode .navbar,
html.day-init .navbar {
    background-color: rgba(255, 255, 255, 0.7);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

body.day-mode .logo-text-desktop,
html.day-init .logo-text-desktop {
    color: #1a202c;
    font-weight: bold;
    text-shadow: none;
}

body.day-mode .nav-btn,
html.day-init .nav-btn {
    background: #ffffff;
    color: #1a202c;
    border: 2px solid #cbd5e0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

body.day-mode .nav-btn::before,
html.day-init .nav-btn::before {
    background: none;
    backdrop-filter: none;
}

body.day-mode .nav-btn::after,
html.day-init .nav-btn::after {
    display: none;
}

body.day-mode .nav-btn:hover:not(:disabled),
html.day-init .nav-btn:hover:not(:disabled) {
    background: #f7fafc;
    border-color: #a0aec0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.page-container {
    max-width: 90rem;
    margin: 0 auto;
    width: 100%;
    position: relative;
    z-index: 2;
    flex: 1;
    padding: 20px 1rem;
}

.header {
    text-align: center;
    margin-bottom: 2rem;
    display: block;
}

.header h1 {
    font-size: 3.5em;
    line-height: 1.2;
    margin-bottom: 1rem;
}

.header h1::after {
    height: 100%;
    -webkit-text-fill-color: transparent;
    display: flex;
    justify-content: center;
    align-items: center;
    white-space: nowrap;
    animation: shad-anim 60s linear infinite;
}

@keyframes shad-anim {
    0% { background-position: 0 0; }
    100% { background-position: 100% -100%; }
}

body.day-mode .header h1,
html.day-init .header h1 {
    color: #2d3748;
    text-shadow: .03em .03em 0 hsla(200, 60%, 60%, 1);
}

.subtitle,
.panel-subtitle {
    color: var(--text-muted);
}

.container {
    background: var(--glass-bg);
    backdrop-filter: blur(20px) saturate(1.2);
    -webkit-backdrop-filter: blur(20px) saturate(1.2);
    border-radius: var(--radius-lg);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
    overflow: hidden;
}

.game-shell {
    grid-template-columns: minmax(260px, 0.85fr) minmax(420px, 1.75fr) minmax(280px, 0.9fr);
    gap: 0;
    align-items: stretch;
}

.section {
    padding: 1.5rem;
    border-right: 1px solid var(--glass-border);
}

.section:last-child {
    border-right: none;
}

.panel-head {
    padding: 0;
    margin-bottom: 1rem;
    border-bottom: none;
}

.panel-head h2 {
    color: var(--text-primary);
    font-size: 1.3rem;
    font-weight: 600;
    display: flex;
    align-items: center;
}

.panel-head h2::before {
    content: '';
    display: inline-block;
    width: 4px;
    height: 20px;
    background: hsl(0, 0%, 80%);
    margin-right: 10px;
    border-radius: 2px;
}

.eyebrow {
    color: var(--text-muted);
}

.game-list {
    padding: 0;
}

.game-card,
.status-card,
.hint-box,
.meta-item,
.analysis-row,
.move-section {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
}

body.day-mode .game-card,
body.day-mode .status-card,
body.day-mode .hint-box,
body.day-mode .meta-item,
body.day-mode .analysis-row,
body.day-mode .move-section,
html.day-init .game-card,
html.day-init .status-card,
html.day-init .hint-box,
html.day-init .meta-item,
html.day-init .analysis-row,
html.day-init .move-section {
    background: rgba(255, 255, 255, 0.6);
    border-color: rgba(0, 0, 0, 0.1);
}

.game-card {
    color: var(--text-primary);
    border-radius: var(--radius-md);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.game-card:hover,
.game-card.is-active {
    transform: translateY(-5px);
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
}

.game-card p,
.status-card span,
.hint-box,
.meta-item,
.analysis-row header,
.move-log {
    color: var(--text-secondary);
}

.mini-badge {
    color: var(--text-secondary);
    border-color: var(--glass-border);
    background: rgba(255, 255, 255, 0.05);
}

.board-panel {
    display: flex;
    flex-direction: column;
}

.btn {
    -webkit-tap-highlight-color: #0000;
    cursor: pointer;
    border-radius: var(--radius-md);
    padding: 12px 24px;
    font-size: 0.95rem;
    background: transparent;
    border: 1px solid transparent;
    position: relative;
    color: white;
    transition: transform 0.1s ease-out, opacity 0.2s;
    display: inline-block;
    font-weight: 500;
    font-family: inherit;
}

.btn::before,
.btn::after {
    content: '';
    position: absolute;
    inset: -1px;
    border-radius: inherit;
    pointer-events: none;
}

.btn::before {
    z-index: -1;
    background: linear-gradient(hsl(0 0% 100% / 0.18), hsl(0 0% 4% / 0.7));
    backdrop-filter: blur(10px) saturate(2);
}

.btn::after {
    box-shadow: 0 0 1px 0.8px hsl(0 0% 100% / 0.8) inset;
    mask: linear-gradient(-35deg, #ffffff80, #ffffff30 30% 60%, #fff);
}

.btn:hover:not(:disabled) {
    transform: translateY(-1px);
    border-color: transparent;
}

body.day-mode .btn,
html.day-init .btn {
    color: #2d3748;
}

.status-grid {
    padding: 0;
    margin-bottom: 1rem;
}

.status-card strong,
.meta-item strong {
    color: var(--text-primary);
}

.board-wrap {
    flex: 1;
    margin: 0 0 1rem;
    border-radius: var(--radius-lg);
    border-color: var(--glass-border);
    background: rgba(0, 0, 0, 0.14);
}

body.day-mode .board-wrap,
html.day-init .board-wrap {
    background: rgba(255, 255, 255, 0.45);
}

.board {
    border-radius: var(--radius-lg);
    border-color: var(--glass-border);
}

.board.tictactoe {
    background: rgba(255, 255, 255, 0.05);
}

.cell {
    border-radius: var(--radius-sm);
    color: var(--text-primary);
}

.cell.legal:not(.occupied):hover {
    box-shadow: 0 0 0 2px rgba(255,255,255,0.35), 0 10px 20px rgba(0,0,0,0.18);
}

.cell.hint::after {
    border-color: var(--accent-highlight);
    box-shadow: 0 0 16px rgba(255,255,255,0.45);
}

.cell.win {
    box-shadow: inset 0 0 0 3px var(--accent-highlight), 0 0 18px rgba(255,255,255,0.3);
}

.piece.x {
    color: #9ee3fb;
}

.piece.o {
    color: #ffdf6d;
}

.hint-box {
    margin: 0;
}

.meta-list,
.analysis-panel,
.move-section {
    padding: 0;
    border-bottom: 0;
}

.meta-list,
.analysis-panel {
    display: grid;
    gap: 0.75rem;
    margin-bottom: 1rem;
}

.meta-item,
.analysis-row,
.move-section {
    padding: 0.8rem;
}

.meta-item {
    border-bottom: 1px solid var(--glass-border);
}

.meta-item:last-child {
    border-bottom: 1px solid var(--glass-border);
}

.bar span {
    background: linear-gradient(90deg, var(--accent-color), var(--accent-highlight));
}

.footer {
    color: var(--text-muted);
}

.theme-toggle {
  --theme-toggle-scale: 0.52;
  position: fixed;
  top: clamp(12px, 2vw, 20px);
  right: clamp(12px, 2vw, 20px);
  z-index: 1000;
  user-select: none;
  transform: scale(var(--theme-toggle-scale));
  transform-origin: top right;
}

.theme-toggle.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.board.qawale {
    --gap: 12px;
    --cell-size: clamp(70px, 14vw, 112px);
    width: fit-content;
    grid-template-columns: 1fr;
    background: linear-gradient(135deg, #6b3f1f, #3f2a1c);
    border-color: rgba(249, 115, 22, 0.34);
    gap: 0.85rem;
}

.qawale-info {
    width: 100%;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 0.65rem;
    color: rgba(255, 247, 237, 0.88);
    font-weight: 700;
}

.qawale-grid {
    display: grid;
    grid-template-columns: repeat(4, var(--cell-size));
    grid-template-rows: repeat(4, var(--cell-size));
    gap: var(--gap);
}

.board.qawale .qawale-cell {
    width: var(--cell-size);
    height: var(--cell-size);
    border-radius: 20px;
    border: 1px solid rgba(251, 191, 36, 0.3);
    background:
        radial-gradient(circle at 30% 20%, rgba(255, 237, 213, 0.32), transparent 36%),
        linear-gradient(135deg, #9a6735, #5a351f);
    box-shadow: inset 0 0 0 2px rgba(255, 255, 255, 0.06), 0 16px 28px rgba(0, 0, 0, 0.22);
    overflow: visible;
}

.board.qawale .qawale-cell.legal {
    box-shadow: inset 0 0 0 3px rgba(56, 189, 248, 0.56), 0 0 22px rgba(56, 189, 248, 0.24);
}

.board.qawale .qawale-cell.current-stack {
    box-shadow: inset 0 0 0 3px rgba(251, 191, 36, 0.74), 0 0 22px rgba(251, 191, 36, 0.3);
}

.qawale-stack {
    position: relative;
    width: 58%;
    height: 58%;
    display: grid;
    place-items: center;
}

.qawale-stone {
    position: absolute;
    width: 82%;
    height: 82%;
    border-radius: 50%;
    transform: translateY(calc(var(--stone-offset, 0) * -6px));
    box-shadow: inset 0 5px 8px rgba(255, 255, 255, 0.22), inset 0 -8px 10px rgba(0, 0, 0, 0.22), 0 7px 12px rgba(0, 0, 0, 0.25);
}

.qawale-stone:nth-child(1) { --stone-offset: 0; }
.qawale-stone:nth-child(2) { --stone-offset: 1; }
.qawale-stone:nth-child(3) { --stone-offset: 2; }
.qawale-stone:nth-child(4) { --stone-offset: 3; }
.qawale-stone:nth-child(5) { --stone-offset: 4; }

.qawale-stone.neutral,
.qawale-top.neutral {
    background: radial-gradient(circle at 35% 28%, #f8e7c3, #c6914a 76%);
}

.qawale-stone.red,
.qawale-top.red {
    background: radial-gradient(circle at 35% 28%, #fca5a5, #b91c1c 74%);
}

.qawale-stone.blue,
.qawale-top.blue {
    background: radial-gradient(circle at 35% 28%, #93c5fd, #1d4ed8 74%);
}

.qawale-top {
    position: absolute;
    right: 0.4rem;
    bottom: 0.4rem;
    width: 1.6rem;
    height: 1.6rem;
    display: grid;
    place-items: center;
    border-radius: 50%;
    border: 1px solid rgba(255, 255, 255, 0.55);
    color: white;
    font-size: 0.78rem;
    font-weight: 800;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.24);
}

body.day-mode .qawale-info,
html.day-init .qawale-info {
    color: #fff7ed;
}

.board.draughts {
    --gap: 0;
    --cell-size: clamp(30px, 7vw, 58px);
    width: fit-content;
    grid-template-columns: repeat(10, var(--cell-size));
    background: #6b4423;
    border-color: rgba(180, 120, 55, 0.5);
    gap: 0;
    padding: clamp(0.5rem, 1.6vw, 0.9rem);
    box-shadow:
        inset 0 0 0 4px rgba(255, 232, 190, 0.12),
        0 18px 42px rgba(0, 0, 0, 0.28);
}

.draughts-cell {
    width: var(--cell-size);
    height: var(--cell-size);
    display: grid;
    place-items: center;
    border: 0;
    padding: 0;
    position: relative;
}

.draughts-cell.light {
    background: #e8cfa3;
    cursor: default;
}

.draughts-cell.dark {
    background: #8b5a2b;
    cursor: pointer;
}

.draughts-cell:disabled {
    cursor: default;
}

.draughts-cell.movable::after,
.draughts-cell.legal::after {
    content: '';
    position: absolute;
    inset: 18%;
    border-radius: 50%;
    pointer-events: none;
}

.draughts-cell.movable::after {
    border: 3px solid rgba(251, 191, 36, 0.72);
}

.draughts-cell.legal.quiet::after {
    background: rgba(14, 165, 233, 0.34);
    border: 2px solid rgba(125, 211, 252, 0.9);
}

.draughts-cell.legal.capture::after {
    background: rgba(239, 68, 68, 0.36);
    border: 2px solid rgba(252, 165, 165, 0.95);
}

.draughts-cell.selected {
    box-shadow: inset 0 0 0 4px rgba(250, 204, 21, 0.85);
}

.draughts-cell.win {
    box-shadow: inset 0 0 0 4px rgba(34, 197, 94, 0.85);
}

.draughts-piece {
    width: 76%;
    height: 76%;
    display: grid;
    place-items: center;
    border-radius: 50%;
    position: relative;
    font-size: clamp(0.78rem, 2.2vw, 1.2rem);
    font-weight: 900;
    line-height: 1;
    box-shadow:
        inset 0 3px 4px rgba(255, 255, 255, 0.34),
        inset 0 -5px 7px rgba(0, 0, 0, 0.28),
        0 6px 10px rgba(0, 0, 0, 0.28);
    z-index: 2;
}

.draughts-piece.draughts-white {
    color: #7c2d12;
    background: #f8fafc;
    border: 2px solid #cbd5e1;
}

.draughts-piece.draughts-black {
    color: #fde68a;
    background: #1f2937;
    border: 2px solid #111827;
}

.draughts-piece.king::before {
    content: '';
    position: absolute;
    width: 42%;
    height: 42%;
    border-radius: 50%;
    border: 2px solid currentColor;
    opacity: 0.72;
}

.board.animalchess {
    --gap: 0;
    --cell-size: clamp(50px, 9.6vw, 82px);
    width: fit-content;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    background: linear-gradient(135deg, #31572c, #132a13);
    border-color: rgba(132, 204, 22, 0.3);
    padding: clamp(0.65rem, 2vw, 1rem);
}

.animalchess-info {
    color: rgba(240, 253, 244, 0.9);
    font-size: 0.86rem;
    font-weight: 700;
    text-align: center;
}

.animalchess-grid {
    display: grid;
    grid-template-columns: repeat(7, var(--cell-size));
    grid-template-rows: repeat(9, var(--cell-size));
    gap: 0;
    padding: clamp(0.35rem, 1.2vw, 0.55rem);
    border-radius: 18px;
    background:
        linear-gradient(rgba(255, 248, 220, 0.1), rgba(255, 248, 220, 0.1)),
        url('../img/animalchess-board.png') center / 100% 100% no-repeat,
        #c69b58;
    border: 2px solid rgba(82, 49, 16, 0.62);
    box-shadow: inset 0 0 0 3px rgba(255, 255, 255, 0.12), 0 18px 34px rgba(0, 0, 0, 0.28);
}

.animalchess-cell {
    width: var(--cell-size);
    height: var(--cell-size);
    border-radius: 0;
    border: 1px solid rgba(89, 55, 20, 0.32);
    background: rgba(244, 214, 153, 0.46);
    overflow: visible;
}

.animalchess-cell.river {
    background: rgba(56, 189, 248, 0.54);
}

.animalchess-cell.den {
    background: rgba(120, 53, 15, 0.5);
}

.animalchess-cell.trap {
    background: rgba(248, 113, 113, 0.42);
}

.animalchess-cell.movable::after,
.animalchess-cell.legal::after {
    content: '';
    position: absolute;
    inset: 14%;
    border-radius: 14px;
    pointer-events: none;
    z-index: 1;
}

.animalchess-cell.movable::after {
    border: 3px solid rgba(250, 204, 21, 0.76);
}

.animalchess-cell.legal.quiet::after {
    background: rgba(34, 197, 94, 0.24);
    border: 2px solid rgba(134, 239, 172, 0.92);
}

.animalchess-cell.legal.capture::after {
    background: rgba(239, 68, 68, 0.3);
    border: 2px solid rgba(252, 165, 165, 0.96);
}

.animalchess-cell.selected {
    box-shadow: inset 0 0 0 4px rgba(250, 204, 21, 0.9);
}

.animalchess-cell.win {
    box-shadow: inset 0 0 0 4px rgba(34, 197, 94, 0.9), 0 0 18px rgba(34, 197, 94, 0.36);
}

.animalchess-piece {
    width: 86%;
    height: 86%;
    object-fit: contain;
    position: relative;
    z-index: 2;
    filter: drop-shadow(0 8px 8px rgba(0, 0, 0, 0.28));
    user-select: none;
}

body.day-mode .board.animalchess,
html.day-init .board.animalchess {
    background: linear-gradient(135deg, #ecfccb, #bbf7d0);
    border-color: rgba(22, 101, 52, 0.22);
    box-shadow: inset 0 0 0 1px rgba(22, 101, 52, 0.1), 0 18px 34px rgba(15, 23, 42, 0.14);
}

body.day-mode .animalchess-info,
html.day-init .animalchess-info {
    color: #14532d;
}

.board.ninechess {
    --nine-board-size: min(78vw, 620px);
    --nine-point-size: clamp(36px, 7vw, 56px);
    width: min(100%, calc(var(--nine-board-size) + 1.5rem));
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    background: linear-gradient(135deg, #4a2c12, #1f1309);
    border-color: rgba(245, 158, 11, 0.32);
    padding: clamp(0.7rem, 2vw, 1rem);
}

.ninechess-info {
    color: rgba(254, 243, 199, 0.92);
    font-size: 0.86rem;
    font-weight: 700;
    text-align: center;
}

.ninechess-board {
    position: relative;
    width: var(--nine-board-size);
    max-width: 100%;
    aspect-ratio: 1 / 1;
    border-radius: 22px;
    background:
        radial-gradient(circle at center, rgba(251, 191, 36, 0.18), transparent 18rem),
        linear-gradient(135deg, #d9a65f, #9a6530);
    border: 2px solid rgba(74, 38, 12, 0.72);
    box-shadow: inset 0 0 0 5px rgba(255, 237, 213, 0.18), 0 18px 34px rgba(0, 0, 0, 0.26);
    overflow: visible;
}

.ninechess-lines {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.ninechess-lines line {
    stroke: rgba(69, 26, 3, 0.72);
    stroke-width: 1.25;
    stroke-linecap: round;
}

.ninechess-point {
    position: absolute;
    width: var(--nine-point-size);
    height: var(--nine-point-size);
    transform: translate(-50%, -50%);
    border-radius: 50%;
    border: 0;
    background: transparent;
    box-shadow: none;
    z-index: 2;
}

.ninechess-point.legal.quiet {
    border-color: rgba(34, 197, 94, 0.92);
    box-shadow: inset 0 0 0 5px rgba(34, 197, 94, 0.22), 0 0 16px rgba(34, 197, 94, 0.32);
}

.ninechess-point.legal.capture {
    border-color: rgba(239, 68, 68, 0.96);
    box-shadow: inset 0 0 0 5px rgba(239, 68, 68, 0.22), 0 0 16px rgba(239, 68, 68, 0.36);
}

.ninechess-point.movable {
    border-color: rgba(250, 204, 21, 0.95);
}

.ninechess-point.selected {
    outline: 4px solid rgba(250, 204, 21, 0.78);
    outline-offset: 3px;
}

.ninechess-point.win {
    box-shadow: inset 0 0 0 5px rgba(34, 197, 94, 0.28), 0 0 18px rgba(34, 197, 94, 0.5);
}

.ninechess-piece {
    width: 92%;
    height: 92%;
    display: grid;
    place-items: center;
    border-radius: 50%;
    font-size: 0;
    box-shadow:
        inset 0 4px 6px rgba(255, 255, 255, 0.36),
        inset 0 -6px 9px rgba(0, 0, 0, 0.26),
        0 7px 12px rgba(0, 0, 0, 0.28);
}

.ninechess-piece.nine-white {
    background: #f8fafc;
    border: 2px solid #cbd5e1;
}

.ninechess-piece.nine-black {
    background: #111827;
    border: 2px solid #020617;
}

body.day-mode .board.ninechess,
html.day-init .board.ninechess {
    background: linear-gradient(135deg, #fff7ed, #fed7aa);
    border-color: rgba(154, 52, 18, 0.24);
    box-shadow: inset 0 0 0 1px rgba(154, 52, 18, 0.1), 0 18px 34px rgba(15, 23, 42, 0.14);
}

body.day-mode .ninechess-info,
html.day-init .ninechess-info {
    color: #7c2d12;
}

.board.chinese-checkers {
    --cc-board-size: min(74vw, 640px);
    --cc-hole: clamp(16px, 3.4vw, 30px);
    width: min(100%, calc(var(--cc-board-size) + 1.75rem));
    max-width: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    background: transparent;
    border-color: transparent;
    box-shadow: none;
}

.chinese-checkers-info {
    color: #3f2b17;
    font-size: 0.86rem;
    font-weight: 700;
    text-align: center;
}

.chinese-checkers-grid {
    position: relative;
    width: var(--cc-board-size);
    max-width: 100%;
    aspect-ratio: 1 / 1.16;
    background: transparent;
    filter: drop-shadow(0 12px 24px rgba(63, 43, 23, 0.25));
    overflow: visible;
}

.chinese-checkers-grid::before {
    content: '';
    position: absolute;
    inset: 0;
    background: #4b2a14;
    clip-path: polygon(50% 0, 100% 25%, 100% 75%, 50% 100%, 0 75%, 0 25%);
    pointer-events: none;
}

.chinese-checkers-grid::after {
    content: '';
    position: absolute;
    inset: 8px;
    background:
        linear-gradient(rgba(218, 178, 123, 0.18), rgba(218, 178, 123, 0.18)),
        url('../img/bg.jpg');
    background-size: cover;
    background-position: center;
    clip-path: polygon(50% 0, 100% 25%, 100% 75%, 50% 100%, 0 75%, 0 25%);
    pointer-events: none;
}

.chinese-checkers-hole {
    position: absolute;
    width: var(--cc-hole);
    height: var(--cc-hole);
    transform: translate(-50%, -50%);
    display: grid;
    place-items: center;
    padding: 0;
    border: 1px solid #80522a;
    border-radius: 50%;
    background: #b98a4f;
    box-shadow: inset 0 2px 5px rgba(50, 29, 12, 0.35), 0 2px 4px rgba(255, 246, 218, 0.22);
    cursor: pointer;
    transition: box-shadow 0.14s ease, background 0.14s ease;
    z-index: 1;
}

.chinese-checkers-hole:disabled {
    cursor: default;
}

.chinese-checkers-hole.legal {
    background: #8fc6dd;
    box-shadow: inset 0 0 0 2px #1d7192, 0 0 0 4px rgba(29, 113, 146, 0.18);
}

.chinese-checkers-hole.jump-move {
    background: #e8c15d;
    box-shadow: inset 0 0 0 2px #9a6a10, 0 0 0 4px rgba(154, 106, 16, 0.18);
}

.chinese-checkers-hole.selected {
    box-shadow: inset 0 0 0 2px #fff4d6, 0 0 0 5px rgba(97, 55, 20, 0.28);
}

.chinese-checkers-hole.win {
    box-shadow: inset 0 0 0 2px #f6d267, 0 0 0 5px rgba(120, 79, 14, 0.3);
}

.chinese-checkers-hole.move-path {
    background: #cda163;
}

.chinese-checkers-piece,
.chinese-checkers-jump-piece {
    width: 82%;
    height: 82%;
    display: grid;
    place-items: center;
    border-radius: 50%;
    color: transparent;
    font-size: 0.56rem;
    line-height: 1;
    text-indent: -999px;
    overflow: hidden;
    border: 1px solid rgba(36, 23, 11, 0.34);
    box-shadow: inset 0 2px 3px rgba(255, 255, 255, 0.38), inset 0 -4px 6px rgba(0, 0, 0, 0.24), 0 6px 10px rgba(0, 0, 0, 0.25);
}

.chinese-checkers-jump-piece {
    position: absolute;
    width: calc(var(--cc-hole) * 0.82);
    height: calc(var(--cc-hole) * 0.82);
    z-index: 8;
    pointer-events: none;
}

.chinese-checkers-piece.cc-red,
.chinese-checkers-jump-piece.cc-red {
    background: #d92d2d;
}

.chinese-checkers-piece.cc-blue,
.chinese-checkers-jump-piece.cc-blue {
    background: #2c63c7;
}

body.day-mode .chinese-checkers-info,
html.day-init .chinese-checkers-info {
    color: #3f2b17;
}

.theme-toggle__btn {
  display: block;
  position: relative;
  width: 125px;
  height: 70px;
  border-radius: 70px;
  border: 5px solid #1c1c1c;
  background-color: #3c4145;
  cursor: pointer;
  transition: all 350ms ease-in;
}

.theme-toggle__btn:focus-visible {
  outline: 3px solid rgba(255, 255, 255, 0.8);
  outline-offset: 4px;
}

body.day-mode .theme-toggle__btn:focus-visible {
  outline-color: rgba(0, 0, 0, 0.55);
}

.theme-toggle__btn::before {
  content: '';
  position: absolute;
  top: 2px;
  left: 2px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background-color: #fff;
  border: 5px solid #e3e3c7;
  transition: all 250ms ease-in;
}

.theme-toggle__btn::after {
  content: '';
  position: absolute;
  top: 62%;
  left: 39px;
  z-index: 10;
  width: 9.2px;
  height: 9.2px;
  opacity: 0;
  background-color: #fff;
  border-radius: 50%;
  box-shadow:
    #fff 0 0,
    #fff 2.5px 0,
    #fff 5px 0,
    #fff 7.5px 0,
    #fff 9px 0,
    #fff 11.5px 0,
    #fff 13px 0,
    #fff 17px -1px 0 1px,
    #fff 13px -6px 0 -2px,
    #fff 6px -6px 0 1px,
    #d3d3d3 0 0 0 3.5px,
    #d3d3d3 5px 0 0 3.5px,
    #d3d3d3 9px 0 0 3.5px,
    #d3d3d3 13px 0 0 3.5px,
    #d3d3d3 17px -1px 0 4.5px,
    #d3d3d3 13px -6px 0 1px,
    #d3d3d3 6px -6px 0 4.5px;
  transition: opacity 100ms ease-in;
}

.theme-toggle__feature {
  display: block;
  position: absolute;
  top: 9px;
  left: 52.5%;
  z-index: 20;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background-color: #fff;
  box-shadow:
    rgba(255,255,255,0.1) 30px -3px 0 0,
    rgba(255,255,255,0.1) 12px 10px 0 -1px,
    #fff 38px 18px 0 1px,
    rgba(255,255,255,0.1) 32px 34px 0 0,
    #fff 20px 24px 0 -1.5px,
    rgba(255,255,255,0.1) 5px 38px 0 1px;
  animation: starry_star 5s ease-in-out infinite;
}

.theme-toggle__feature::before {
  content: '';
  position: absolute;
  top: -2px;
  left: -25px;
  width: 15px;
  height: 15px;
  background-color: #fff;
  border-radius: 50%;
  border: 4px solid #e3e3c7;
  box-shadow:
    #e3e3c7 -28px 0 0 -3px,
    #e3e3c7 -8px 24px 0 -2px;
  transform-origin: -6px 130%;
  transition: all 250ms ease-in;
}

@keyframes starry_star {
  50% {
    background-color: rgba(255,255,255,0.1);
    box-shadow:
      #fff 30px -3px 0 0,
      #fff 12px 10px 0 -1px,
      rgba(255,255,255,0.1) 38px 18px 0 1px,
      #fff 32px 34px 0 0,
      rgba(255,255,255,0.1) 20px 24px 0 -1.5px,
      #fff 5px 38px 0 1px;
  }
}

@keyframes bounceIn {
  0% {
    opacity: 0;
    transform: scale(.3);
  }
  50% {
    opacity: 1;
    transform: scale(1.1);
  }
  55% {
    transform: scale(1.1);
  }
  75% {
    transform: scale(.9);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}

.theme-toggle__btn.is-day {
  background-color: #9ee3fb;
  border: 5px solid #86c3d7;
}

.theme-toggle__btn.is-day::before {
  left: 57px;
  background-color: #ffdf6d;
  border: 5px solid #e1c348;
}

.theme-toggle__btn.is-day::after {
  opacity: 1;
  animation-name: bounceIn;
  animation-duration: 0.60s;
  animation-delay: 0.10s;
  animation-fill-mode: backwards;
  animation-timing-function: ease-in-out;
}

.theme-toggle__btn.is-day .theme-toggle__feature {
  opacity: 0;
  box-shadow:
    rgba(255,255,255,0.1) 30px -3px 0 -4px,
    rgba(255,255,255,0.1) 12px 10px 0 -5px,
    #fff 38px 18px 0 -3px,
    rgba(255,255,255,0.1) 32px 34px 0 -4px,
    #fff 20px 24px 0 -5.5px,
    rgba(255,255,255,0.1) 5px 38px 0 -3px;
  animation: none;
}

.theme-toggle__btn.is-day .theme-toggle__feature::before {
  left: 25px;
  transform: rotate(70deg);
}

@media (min-width: 769px) and (max-width: 1024px) {
  .theme-toggle {
    --theme-toggle-scale: 0.47;
  }
}

@media (max-width: 768px) {
  .theme-toggle {
    --theme-toggle-scale: 0.42;
    position: absolute;
    top: calc(env(safe-area-inset-top, 0px) + 10px);
    right: 10px;
    z-index: 2;
  }
}

.navbar .theme-toggle-container {
  width: 60px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.navbar .theme-toggle {
  position: relative;
  top: auto;
  right: auto;
  bottom: auto;
  left: auto;
  z-index: 1000;
  user-select: none;
  transform: scale(0.45);
  transform-origin: center;
}

@media (max-width: 1180px) {
    .game-shell {
        grid-template-columns: minmax(240px, 0.9fr) minmax(420px, 1.6fr);
    }

    .control-panel {
        grid-column: 1 / -1;
        border-top: 1px solid var(--glass-border);
        border-right: none;
    }
}

@media (max-width: 820px) {
    .nav-content {
        flex-direction: column;
        gap: 0.75rem;
        align-items: center;
        padding: 0.75rem 1rem;
    }

    .logo-wrapper,
    .nav-actions {
        justify-content: center;
        width: 100%;
    }

    .game-shell {
        grid-template-columns: 1fr;
    }

    .section {
        border-right: none;
        border-bottom: 1px solid var(--glass-border);
    }

    .section:last-child {
        border-bottom: none;
    }

    .panel-head,
    .board-head {
        flex-direction: column;
        align-items: stretch;
    }

    .header h1 {
        font-size: 2.6em;
    }
}

body.day-mode,
html.day-init body {
    --bg-dark: #f0f4f8;
    --bg-panel: #f0f4f8;
    --text-primary: #2d3748;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --text-placeholder: #a0aec0;
    --glass-bg: rgba(255, 255, 255, 0.6);
    --glass-border: rgba(0, 0, 0, 0.1);
    --glass-shadow: 5px 3px 30px rgba(0, 0, 0, 0.1);
    --input-bg: rgba(255, 255, 255, 0.7);
    --input-focus-bg: #fff;
    --input-border: rgba(0, 0, 0, 0.15);
    color: #2d3748;
    background-color: #f0f4f8;
    background-image: url(../../../../assets/image/day-background.png);
    background-size: auto;
    background-repeat: repeat;
}

body.day-mode .container,
html.day-init .container {
    background: hsla(0, 0%, 100%, 0.6);
    border-color: rgba(200, 200, 200, 0.4);
}

body.day-mode .btn,
html.day-init .btn {
    background: #ffffff;
    color: #1a202c;
    border: 1px solid #cbd5e0;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

body.day-mode .btn::before,
body.day-mode .btn::after,
html.day-init .btn::before,
html.day-init .btn::after {
    display: none;
}

body.day-mode .btn:hover:not(:disabled),
html.day-init .btn:hover:not(:disabled) {
    background: #f7fafc;
    border-color: #a0aec0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.footer {
    position: relative;
    z-index: 1;
    width: 100%;
    padding: 2rem 1rem;
    text-align: center;
    margin-top: 3rem;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.footer p {
    margin: 0;
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.4);
    transition: color 300ms ease-out;
    line-height: 1.8;
}

body.day-mode .footer,
html.day-init .footer {
    border-top-color: rgba(0, 0, 0, 0.1);
}

body.day-mode .footer p,
html.day-init .footer p {
    color: rgba(0, 0, 0, 0.5);
}

.game-shell {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0;
    align-items: stretch;
}

.section {
    border-right: none;
    border-bottom: 1px solid var(--glass-border);
}

.section:last-child {
    border-bottom: none;
}

.game-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 0.85rem;
}

.board-toolbar {
    align-items: center;
}

@media (min-width: 821px) {
    .board-head {
        align-items: flex-start;
    }
}

.board-head #gameTitle {
    margin-top: 0;
}

.size-control {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.size-control label {
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 600;
}

.size-control input {
    width: 5.5rem;
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-md);
    background: var(--input-bg);
    color: var(--text-primary);
    padding: 0.7rem 0.8rem;
    font: inherit;
}

.board-wrap {
    min-height: clamp(28rem, 62vw, 46rem);
}

.board.gomoku {
    --cell-size: clamp(18px, 3.6vw, 34px);
}

.board.reversi {
    --cell-size: clamp(26px, 5vw, 54px);
}

.board.tictactoe {
    --cell-size: clamp(44px, 10vw, 110px);
}

@media (max-width: 640px) {
    .board-head,
    .board-toolbar,
    .size-control {
        align-items: stretch;
    }

    .size-control input,
    .size-control .btn {
        flex: 1 1 auto;
    }
}

.game-card {
    border-radius: 14px;
    padding: 0.85rem 0.95rem;
    gap: 0.35rem;
    background: rgba(255, 255, 255, 0.035);
}

.game-card:hover,
.game-card.is-active {
    transform: none;
    background: color-mix(in srgb, var(--game-color), transparent 86%);
}

.game-card h3 {
    font-size: 1rem;
}

.game-card p {
    line-height: 1.45;
    font-size: 0.86rem;
}

.meta-item {
    display: grid;
    gap: 0.5rem;
    padding: 1rem;
    border: 1px solid var(--glass-border);
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.04);
}

.meta-item:last-child {
    padding-bottom: 1rem;
}

.meta-item span {
    color: var(--text-muted);
    font-size: 0.78rem;
    line-height: 1.35;
    font-weight: 700;
    letter-spacing: 0.04em;
}

.meta-item strong {
    text-align: left;
    line-height: 1.55;
    font-weight: 600;
    color: var(--text-primary);
}

.meta-value {
    margin: 0;
    color: var(--text-primary);
    font-size: 0.95rem;
    font-weight: 400;
    line-height: 1.65;
    text-align: right;
}

.meta-item-wide {
    grid-column: 1 / -1;
}

body.day-mode .meta-item,
html.day-init .meta-item {
    background: rgba(255, 255, 255, 0.62);
}

.move-log {
    height: clamp(12rem, 24vw, 18rem);
    overflow-y: auto;
    overflow-x: hidden;
    align-content: start;
    padding: 0.75rem 0.9rem 0.75rem 2rem;
    border: 1px solid var(--glass-border);
    border-radius: 14px;
    background: rgba(255, 255, 255, 0.035);
    scrollbar-width: thin;
    scrollbar-color: rgba(255, 255, 255, 0.28) transparent;
}

.move-log::-webkit-scrollbar {
    width: 8px;
}

.move-log::-webkit-scrollbar-track {
    background: transparent;
}

.move-log::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.22);
    border-radius: 999px;
}

body.day-mode .move-log,
html.day-init .move-log {
    background: rgba(255, 255, 255, 0.5);
    scrollbar-color: rgba(0, 0, 0, 0.22) transparent;
}

body.day-mode .move-log::-webkit-scrollbar-thumb,
html.day-init .move-log::-webkit-scrollbar-thumb {
    background: rgba(0, 0, 0, 0.18);
}

.meta-list {
    grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
    gap: 0.85rem;
}