* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #43cea2 0%, #185a9d 100%);
    min-height: 100vh;
    color: #222;
    padding: 20px;
}
.game-container {
    max-width: 400px;
    margin: 0 auto;
    background: rgba(255,255,255,0.97);
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.13);
    padding: 30px;
    border: 2px solid rgba(67,206,162,0.12);
}
.game-header {
    text-align: center;
    margin-bottom: 24px;
    border-bottom: 3px solid #43cea2;
    padding-bottom: 16px;
}
.game-header h1 {
    font-size: 2rem;
    color: #43cea2;
    margin-bottom: 8px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.07);
    font-weight: bold;
}
.game-status {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 18px;
    font-size: 1.1rem;
    margin-bottom: 8px;
}
.score-label {
    color: #43cea2;
    font-weight: bold;
}
.score-value {
    padding: 4px 10px;
    border-radius: 8px;
    background: #e0f7fa;
    color: #43cea2;
    font-weight: bold;
    font-size: 1.1rem;
    border: 1px solid #43cea2;
}
.game-btn {
    padding: 8px 18px;
    font-size: 1rem;
    border: none;
    border-radius: 8px;
    background: linear-gradient(45deg, #43cea2, #185a9d);
    color: white;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.08);
}
.game-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(67,206,162,0.12);
    background: linear-gradient(45deg, #185a9d, #43cea2);
}
.game-btn:active {
    transform: translateY(0);
}
.game-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}
.game-board-container {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 24px;
}
.board {
    display: grid;
    grid-template-columns: repeat(2, 100px);
    grid-template-rows: repeat(2, 100px);
    gap: 16px;
    background: #e0f7fa;
    border-radius: 12px;
    padding: 16px;
}
.color-btn {
    width: 100px;
    height: 100px;
    border-radius: 16px;
    cursor: pointer;
    box-shadow: 0 2px 6px rgba(67,206,162,0.08);
    transition: filter 0.2s, opacity 0.2s;
    opacity: 0.85;
}
#green { background: #43cea2; }
#red { background: #e94e77; }
#yellow { background: #ffe156; }
#blue { background: #185a9d; }
.color-btn.active {
    filter: brightness(1.5);
    opacity: 1;
}
.instructions {
    background: rgba(67,206,162,0.08);
    border-radius: 15px;
    padding: 16px;
    border: 2px solid rgba(67,206,162,0.12);
    margin-top: 10px;
}
.instructions h3 {
    color: #43cea2;
    margin-bottom: 8px;
    text-align: center;
    font-size: 1.1rem;
}
.instructions ul {
    margin-left: 20px;
    color: #222;
    font-size: 1rem;
}