:root {
    --bg-dark: #0f172a;
    --panel-bg: rgba(30, 41, 59, 0.7);
    --primary: #3b82f6;
    --glass-border: rgba(255, 255, 255, 0.1);
    
    --card-red: #ef4444;
    --card-blue: #3b82f6;
    --card-green: #22c55e;
    --card-yellow: #eab308;
    --card-black: #1e293b;
    --card-width: 70px;
    --card-height: 105px;
}

body {
    background-color: var(--bg-dark);
    color: white;
    font-family: 'Outfit', sans-serif;
    margin: 0;
    overflow-x: hidden;
}

.game-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem 1rem;
    position: relative;
    z-index: 10;
}

.game-header { text-align: center; }
.game-header h1 { font-size: 2.5rem; margin: 1rem 0 0 0; }

.panel {
    background: var(--panel-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 2rem;
    max-width: 400px;
    margin: 2rem auto;
    text-align: center;
}

.btn-group { display: flex; flex-direction: column; gap: 0.75rem; margin-top: 1.5rem; }

/** Game Area */
.player-area {
    margin: 1rem 0;
    text-align: center;
}
.player-area h3 {
    margin: 0 0 0.5rem 0;
    font-size: 1rem;
    color: #94a3b8;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.hand {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: -30px; /* overlapping cards slightly */
    min-height: var(--card-height);
    padding: 10px;
}

.hand .card {
    margin-left: -20px;
    transition: transform 0.2s, margin 0.2s;
}
.hand .card:first-child {
    margin-left: 0;
}

.active-hand .card:hover {
    transform: translateY(-20px);
    z-index: 20;
    margin-right: 15px; /* push siblings so it's readable */
}

.center-table {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 2rem 0;
    background: rgba(0,0,0,0.2);
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid var(--glass-border);
}

.deck-area {
    display: flex;
    gap: 2rem;
    perspective: 1000px;
}

.call-uno-btn {
    margin-top: 1rem;
    background: #ef4444;
    color: white;
    font-weight: bold;
    padding: 0.5rem 1.5rem;
    border-radius: 30px;
    cursor: pointer;
    text-transform: uppercase;
    animation: pulse 1s infinite alternate;
    box-shadow: 0 0 15px rgba(239, 68, 68, 0.5);
    border: 2px solid white;
}
.call-uno-btn:active { transform: scale(0.9); }

@keyframes pulse {
    0% { transform: scale(1); }
    100% { transform: scale(1.1); }
}

/** Card CSS */
.card {
    width: var(--card-width);
    height: var(--card-height);
    perspective: 1000px;
    cursor: pointer;
    user-select: none;
    position: relative;
    border-radius: 8px;
    box-shadow: 2px 2px 8px rgba(0,0,0,0.3);
}

.card-inner {
    width: 100%;
    height: 100%;
    border-radius: 8px;
    border: 4px solid white;
    background: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Outfit', sans-serif;
    font-weight: 900;
    font-size: 2rem;
    box-sizing: border-box;
    position: relative;
    overflow: hidden;
}

.card-inner::after {
    /* internal oval */
    content: '';
    position: absolute;
    width: 80%;
    height: 80%;
    background: white;
    border-radius: 50% / 60%;
    transform: rotate(-25deg);
    z-index: 1;
}

.card-val {
    position: relative;
    z-index: 2;
    text-shadow: 1px 1px 0px rgba(0,0,0,0.2);
}

/* Colors */
.card[data-color="red"] .card-inner { background: var(--card-red); border-color: white; }
.card[data-color="red"] .card-val { color: var(--card-red); }

.card[data-color="blue"] .card-inner { background: var(--card-blue); }
.card[data-color="blue"] .card-val { color: var(--card-blue); }

.card[data-color="green"] .card-inner { background: var(--card-green); }
.card[data-color="green"] .card-val { color: var(--card-green); }

.card[data-color="yellow"] .card-inner { background: var(--card-yellow); }
.card[data-color="yellow"] .card-val { color: var(--card-yellow); }

.card[data-color="black"] .card-inner { background: var(--card-black); }
.card[data-color="black"] .card-val { color: var(--card-black); font-size: 1.5rem;}
.card[data-color="black"] .card-inner::after { background: linear-gradient(45deg, var(--card-red), var(--card-yellow), var(--card-green), var(--card-blue)); }

.card-mini-val {
    position: absolute;
    top: 2px;
    left: 4px;
    font-size: 0.8rem;
    z-index: 3;
    color: white;
}
.card-mini-val.br {
    top: auto; bottom: 2px;
    left: auto; right: 4px;
    transform: rotate(180deg);
}

.deck-back {
    background: #1e293b !important;
    color: white;
    font-size: 1rem;
    border-color: white !important;
}
.deck-back::after { display: none; }

.card.invalid {
    opacity: 0.5;
    filter: grayscale(0.8);
    cursor: not-allowed;
}

.color-options {
    display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap;
}
.color-btn {
    width: 60px; height: 60px; border-radius: 50%; border: 4px solid white; cursor: pointer; transition: transform 0.2s;
}
.color-btn:hover { transform: scale(1.1); }
.red-btn { background: var(--card-red); }
.blue-btn { background: var(--card-blue); }
.green-btn { background: var(--card-green); }
.yellow-btn { background: var(--card-yellow); }

.hidden { display: none !important; }

@media (max-width: 600px) {
    :root {
        --card-width: 50px;
        --card-height: 75px;
    }
    .card-inner { font-size: 1.5rem; border-width: 2px; }
    .card-mini-val { font-size: 0.6rem; }
    .hand .card { margin-left: -25px; }
}