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

header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 16px;
    background: #1a472a;
    color: #fff;
    touch-action: pan-y;
    /* ← 縦スクロールを許可 */

}

header h1 {
    font-size: 1.4rem;
}

header a {
    color: #fff;
    text-decoration: none;
    font-size: 1.1rem;
}

body {
    background: #0a0a0a;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

#ad_container {
    margin: 12px 0;
    text-align: center;
}

#game-wrap {
    line-height: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    flex: 1;
}

#description {
    max-width: 800px;
    margin: 20px auto;
    padding: 0 16px;
    color: #ccc;
}

#description ul {
    padding-left: 1.8em;
}

#description h2 {
    margin: 24px 0 8px;
}

#description h3 {
    margin: 20px 0 6px;
}


footer {
    text-align: center;
    padding: 8px 16px;
    background: #1a472a;
    color: #fff;
}

footer a {
    color: #fff;
}

canvas {
    display: block;
    cursor: crosshair;
    /* 縦長スマホ: 92vw、横長スマホ: 90vh基準、PC: 480px上限 */
    width: min(480px, 92vw, calc(90vh * 0.75));
    aspect-ratio: 480 / 640;
    touch-action: none;
}