* {
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    margin: 0;
    padding: 0;
    font-family: Arial, sans-serif;
    background: #f8f9fa;
    overflow-x: hidden;
    touch-action: manipulation;
}

canvas {
    border: 2px solid #333;
    display: block;
    margin: 10px auto;
    max-width: 100%;
    max-height: calc(100vh - 180px);
    width: auto;
    height: auto;
    touch-action: none;
}

.ui {
    text-align: center;
    padding: 15px 10px;
    font-size: clamp(16px, 4vw, 20px);
}

.ui > div {
    margin: 8px 0;
}

button {
    font-size: clamp(14px, 3.5vw, 18px);
    padding: 8px 16px;
    margin: 5px;
    min-height: 44px;
    cursor: pointer;
    border: 2px solid #333;
    background: white;
    border-radius: 4px;
}

button:active {
    background: #e0e0e0;
}

input[type="number"] {
    font-size: clamp(14px, 3.5vw, 18px);
    padding: 8px;
    width: 80px;
    border: 2px solid #333;
    border-radius: 4px;
    text-align: center;
}

label {
    margin-right: 5px;
}

.rules {
    max-width: 600px;
    margin: 20px auto;
    padding: 0 20px;
    text-align: left;
}

.rules summary {
    font-size: clamp(16px, 4vw, 18px);
    font-weight: bold;
    cursor: pointer;
    padding: 12px 16px;
    background: white;
    border: 2px solid #333;
    border-radius: 4px;
    list-style: none;
    user-select: none;
    text-align: center;
}

.rules summary::-webkit-details-marker {
    display: none;
}

.rules summary:hover {
    background: #f0f0f0;
}

.rules-content {
    padding: 16px;
    background: white;
    border: 2px solid #333;
    border-top: none;
    border-radius: 0 0 4px 4px;
    margin-top: -2px;
}

.rules-content h3 {
    margin: 16px 0 8px 0;
    font-size: clamp(15px, 3.5vw, 17px);
    color: #333;
}

.rules-content h3:first-child {
    margin-top: 0;
}

.rules-content p {
    margin: 8px 0;
    font-size: clamp(14px, 3vw, 16px);
    line-height: 1.5;
}

.rules-content ul {
    margin: 8px 0;
    padding-left: 24px;
}

.rules-content li {
    margin: 6px 0;
    font-size: clamp(14px, 3vw, 16px);
    line-height: 1.5;
}

@media (max-width: 600px) {
    .ui {
        padding: 10px 5px;
    }

    canvas {
        margin: 5px auto;
        max-height: calc(100vh - 160px);
    }

    button {
        padding: 10px 12px;
        margin: 3px;
    }

    .rules {
        padding: 0 10px;
        margin: 15px auto;
    }

    .rules summary {
        padding: 10px 12px;
    }

    .rules-content {
        padding: 12px;
    }
}