/* style.css */
:root {
    --bg-color: #050505;
    --neon-cyan: #00f3ff;
    --neon-purple: #bc13fe;
    --text-color: #ffffff;
    --cell-bg: rgba(20, 20, 25, 0.6);
    --border-color: rgba(0, 243, 255, 0.3);
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Orbitron', sans-serif;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    position: relative;
}

/* Background Effects */
.background-triangles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
    background: 
        linear-gradient(45deg, transparent 48%, #111 49%, #111 51%, transparent 52%), 
        linear-gradient(-45deg, transparent 48%, #111 49%, #111 51%, transparent 52%);
    background-size: 60px 60px;
    opacity: 0.3;
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, transparent 0%, var(--bg-color) 90%);
    z-index: -1;
    pointer-events: none;
}

.container {
    text-align: center;
    z-index: 10;
    padding: 20px;
}

.neon-text {
    font-size: 4rem;
    margin-bottom: 2rem;
    color: #fff;
    text-shadow: 
        0 0 5px #fff,
        0 0 10px #fff,
        0 0 20px var(--neon-cyan),
        0 0 40px var(--neon-cyan);
    letter-spacing: 5px;
}

/* Bingo Card Structure */
.bingo-card {
    display: flex;
    flex-direction: column;
    gap: 10px;
    background: rgba(255, 255, 255, 0.05);
    padding: 20px;
    border: 1px solid var(--border-color);
    box-shadow: 0 0 20px rgba(0, 243, 255, 0.1);
    backdrop-filter: blur(5px);
    margin-bottom: 30px;
    position: relative;
}

/* Setup Triangles on Card Corners via CSS clip-path or pseudo-elements */
.bingo-card::before {
    content: '';
    position: absolute;
    top: -2px; left: -2px;
    width: 20px; height: 20px;
    border-top: 2px solid var(--neon-cyan);
    border-left: 2px solid var(--neon-cyan);
}
.bingo-card::after {
    content: '';
    position: absolute;
    bottom: -2px; right: -2px;
    width: 20px; height: 20px;
    border-bottom: 2px solid var(--neon-cyan);
    border-right: 2px solid var(--neon-cyan);
}

.bingo-row {
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    gap: 8px;
}

.bingo-cell {
    width: 60px;
    height: 80px;
    display: flex;
    justify-content: center;
    align-items: center;
    background: var(--cell-bg);
    border: 1px solid #333;
    font-size: 1.5rem;
    font-weight: bold;
    position: relative;
    cursor: pointer;
    transition: all 0.3s ease;
    clip-path: polygon(10% 0, 100% 0, 100% 90%, 90% 100%, 0 100%, 0 10%);
}

.bingo-cell.empty {
    background: transparent;
    border-color: transparent;
    cursor: default;
    pointer-events: none; /* Disable clicking empty cells */
}

.bingo-cell.filled {
    color: var(--neon-cyan);
}

.bingo-cell.filled:hover {
    background: rgba(0, 243, 255, 0.1);
    border-color: var(--neon-cyan);
    box-shadow: 0 0 10px var(--neon-cyan);
}

.bingo-cell.marked {
    background: var(--neon-purple); /* Fill when marked */
    color: #fff;
    border-color: var(--neon-purple);
    box-shadow: 0 0 15px var(--neon-purple);
    text-shadow: 0 0 5px #fff;
}

/* Controls */
.controls {
    margin-top: 20px;
}

.neon-btn {
    background: transparent;
    color: var(--neon-cyan);
    font-family: 'Orbitron', sans-serif;
    font-size: 1.2rem;
    padding: 15px 30px;
    border: 2px solid var(--neon-cyan);
    cursor: pointer;
    text-transform: uppercase;
    transition: 0.3s;
    position: relative;
    overflow: hidden;
}

.neon-btn:hover {
    background: var(--neon-cyan);
    color: #000;
    box-shadow: 0 0 20px var(--neon-cyan);
}

.footer-text {
    margin-top: 2rem;
    font-size: 0.8rem;
    color: #666;
}

@media (max-width: 700px) {
    .bingo-row {
        gap: 2px;
    }
    .bingo-cell {
        width: 35px;
        height: 50px;
        font-size: 0.9rem;
    }
}