:root {
    --green-default: #00a74a;
    --green-flash: #13ff7c;
    --red-default: #9f0f17;
    --red-flash: #ff4139;
    --yellow-default: #ccb900;
    --yellow-flash: #ffff40;
    --blue-default: #094a8f;
    --blue-flash: #1c8cff;
    --center-bg: #303030;
    --body-bg: #0d1117;
}

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

body {
    font-family: Arial, sans-serif;
    background-color: var(--body-bg);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
}

#game-container {
    text-align: center;
}

h1 {
    font-size: 2.5rem;
    margin-bottom: 20px;
    color: #c9d1d9;
}

#simon-game {
    position: relative;
    width: 400px;
    height: 400px;
    margin: 0 auto;
    border-radius: 50%;
    background: var(--center-bg);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.4);
    border: 15px solid #202020;
}

/* Quadrants Layout */
#quadrants {
    width: 100%;
    height: 100%;
    border-radius: 50%;
    overflow: hidden;
    display: grid;
    grid-template-columns: 1fr 1fr;
    grid-template-rows: 1fr 1fr;
}

.quadrant {
    cursor: pointer;
    border: none;
    transition: background-color 0.1s;
}

/* Quadrant Specific Colors */
#green { background-color: var(--green-default); border-radius: 100% 0 0 0; }
#red { background-color: var(--red-default); border-radius: 0 100% 0 0; }
#yellow { background-color: var(--yellow-default); border-radius: 0 0 0 100%; }
#blue { background-color: var(--blue-default); border-radius: 0 0 100% 0; }

/* Center Display */
#center-display {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 45%;
    height: 45%;
    background-color: var(--center-bg);
    border-radius: 50%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.5) inset;
    padding: 10px;
    color: #fff;
}

#score-display {
    font-size: 1rem;
    font-weight: bold;
    color: var(--light-color);
    margin-bottom: 10px;
}
#score-value {
    color: var(--light-color);
}

#message {
    font-size: 0.8rem;
    margin-top: 5px;
    color: #8b949e;
}

/* Button */
#start-button {
    background-color: var(--green-default);
    color: white;
    padding: 8px 15px;
    border: 2px solid #fff;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    transition: background-color 0.2s;
    font-size: 1rem;
}

#start-button:hover:not(:disabled) {
    background-color: var(--green-flash);
}
#start-button:disabled {
    cursor: not-allowed;
    opacity: 0.5;
}

/* Flash Animation Classes */
.quadrant.flash-green { background-color: var(--green-flash); }
.quadrant.flash-red { background-color: var(--red-flash); }
.quadrant.flash-yellow { background-color: var(--yellow-flash); }
.quadrant.flash-blue { background-color: var(--blue-flash); }