/* ═══════════════════════════════════════════
   經典接龍 Klondike — Styles
   ═══════════════════════════════════════════ */
* { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    --card-w: 80px;
    --card-h: 112px;
    --card-radius: 8px;
    --pile-gap: 12px;
    --tableau-offset-hidden: 6px;
    --tableau-offset-visible: 26px;
    --bg: #1b6e2d;
    --bg-dark: #145523;
    --card-back: #2c5aa0;
    --card-front: #fff;
    --card-red: #d32f2f;
    --card-black: #212121;
    --shadow: rgba(0,0,0,.35);
}

body {
    font-family: 'Segoe UI', 'Noto Sans TC', Arial, sans-serif;
    background: var(--bg);
    color: #fff;
    min-height: 100vh;
    user-select: none;
    -webkit-user-select: none;
    overflow-x: hidden;
}

/* ═══ 工具列 ═══ */
.toolbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 16px;
    background: var(--bg-dark);
    box-shadow: 0 2px 8px rgba(0,0,0,.3);
    position: sticky;
    top: 0;
    z-index: 100;
}

.game-title {
    font-size: 1.2rem;
    font-weight: 700;
    letter-spacing: 1px;
}

.toolbar-right {
    display: flex;
    align-items: center;
    gap: 14px;
}

.stat {
    font-size: .85rem;
    color: #c8e6c9;
}

.btn {
    padding: 6px 16px;
    border: none;
    border-radius: 6px;
    font-size: .85rem;
    font-weight: 600;
    cursor: pointer;
    transition: all .15s;
}

.btn-new {
    background: #ffca28;
    color: #333;
}
.btn-new:hover { background: #ffd54f; }

.btn-undo {
    background: rgba(255,255,255,.15);
    color: #fff;
    font-size: 1.1rem;
    padding: 4px 10px;
}
.btn-undo:hover { background: rgba(255,255,255,.25); }

/* ═══ 遊戲區域 ═══ */
#game-area {
    padding: 16px;
    max-width: 700px;
    margin: 0 auto;
}

.top-row {
    display: flex;
    justify-content: space-between;
    margin-bottom: 20px;
}

.stock-waste {
    display: flex;
    gap: var(--pile-gap);
}

.foundations {
    display: flex;
    gap: var(--pile-gap);
}

.tableau-row {
    display: flex;
    gap: var(--pile-gap);
    justify-content: center;
}

/* ═══ 牌堆 (空位) ═══ */
.pile {
    width: var(--card-w);
    min-height: var(--card-h);
    border-radius: var(--card-radius);
    position: relative;
    flex-shrink: 0;
}

.pile.stock,
.pile.waste,
.pile.foundation {
    height: var(--card-h);
}

/* 空位指示 */
.pile.foundation::before,
.pile.stock::before {
    content: '';
    position: absolute;
    inset: 0;
    border: 2px dashed rgba(255,255,255,.25);
    border-radius: var(--card-radius);
    pointer-events: none;
}

.pile.foundation::after {
    content: attr(data-label);
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    font-size: 1.8rem;
    opacity: .2;
    pointer-events: none;
}

.pile.stock::after {
    content: '🔄';
    position: absolute;
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    font-size: 1.5rem;
    opacity: .3;
    pointer-events: none;
}

.pile.tableau {
    min-height: calc(var(--card-h) + 200px);
}

/* ═══ 撲克牌 ═══ */
.card {
    width: var(--card-w);
    height: var(--card-h);
    border-radius: var(--card-radius);
    position: absolute;
    left: 0;
    cursor: pointer;
    transition: box-shadow .15s, transform .15s;
    font-family: 'Segoe UI', Arial, sans-serif;
    box-shadow: 0 1px 3px var(--shadow);
}

.card:hover {
    box-shadow: 0 4px 12px var(--shadow);
}

/* 背面 */
.card.face-down {
    background: var(--card-back);
    background-image:
        repeating-linear-gradient(45deg, transparent, transparent 4px, rgba(255,255,255,.06) 4px, rgba(255,255,255,.06) 8px);
    border: 2px solid #1e3f6f;
    cursor: default;
}

/* 正面 */
.card.face-up {
    background: var(--card-front);
    border: 1px solid #ccc;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    padding: 4px 6px;
}

.card.face-up.red { color: var(--card-red); }
.card.face-up.black { color: var(--card-black); }

.card-corner {
    display: flex;
    flex-direction: column;
    align-items: center;
    line-height: 1;
}

.card-corner .rank {
    font-size: .85rem;
    font-weight: 700;
}

.card-corner .suit {
    font-size: .7rem;
}

.card-corner-br {
    align-self: flex-end;
    transform: rotate(180deg);
}

.card-center {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 1.8rem;
}

/* 拖曳中 */
.card.dragging {
    z-index: 9999 !important;
    box-shadow: 0 8px 24px rgba(0,0,0,.5);
    transform: rotate(2deg);
    opacity: .92;
    pointer-events: none;
}

/* 選中 */
.card.selected {
    box-shadow: 0 0 0 3px #ffca28, 0 4px 12px var(--shadow);
}

/* ═══ 勝利彈窗 ═══ */
#win-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,.6);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2000;
    backdrop-filter: blur(4px);
}

.win-box {
    background: #1a3a20;
    border: 2px solid #4caf50;
    border-radius: 16px;
    padding: 40px;
    text-align: center;
    max-width: 360px;
    width: 90%;
    animation: popIn .3s ease;
}

@keyframes popIn {
    from { transform: scale(.8); opacity: 0; }
    to { transform: scale(1); opacity: 1; }
}

.win-icon { font-size: 3.5rem; margin-bottom: 12px; }
.win-title { font-size: 1.5rem; font-weight: 700; margin-bottom: 8px; }
.win-stats { color: #a5d6a7; font-size: .9rem; margin-bottom: 24px; }

/* ═══ RWD ═══ */
@media (max-width: 620px) {
    :root {
        --card-w: 48px;
        --card-h: 68px;
        --pile-gap: 6px;
        --tableau-offset-hidden: 4px;
        --tableau-offset-visible: 18px;
    }
    #game-area { padding: 8px; }
    .card-corner .rank { font-size: .65rem; }
    .card-corner .suit { font-size: .55rem; }
    .card-center { font-size: 1.2rem; }
    .game-title { font-size: 1rem; }
    .stat { font-size: .75rem; }
}

@media (max-width: 400px) {
    :root {
        --card-w: 40px;
        --card-h: 58px;
        --pile-gap: 4px;
        --tableau-offset-hidden: 3px;
        --tableau-offset-visible: 14px;
    }
}