body {
    font-family: 'Roboto', Arial, sans-serif;
    background-color: #f0f2f5;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    flex-direction: column;
}

h1 {
    font-size: 2rem;
    color: #333;
    margin-bottom: 20px;
}

ul {
    list-style: none;
    padding: 0;
}

li {
    margin: 10px 0;
}

a {
    display: inline-block;
    padding: 10px 20px;
    font-size: 1rem;
    color: #fff;
    background-color: #007bff;
    border-radius: 5px;
    text-decoration: none;
    transition: background-color 0.3s, transform 0.2s;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

a:hover {
    background-color: #0056b3;
    transform: translateY(-2px);
    box-shadow: 0 6px 8px rgba(0, 0, 0, 0.15);
}

a:active {
    transform: translateY(0);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.back-to-top-footer {
    text-align: center;
    margin: 48px 0 16px 0;
}

.back-to-top-link {
    display: inline-block;
    padding: 7px 20px;
    background: linear-gradient(90deg, #ffb347 0%, #ffcc33 100%);
    color: #333;
    border-radius: 18px;
    text-decoration: none;
    font-weight: bold;
    font-size: 1em;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    transition: background 0.2s, color 0.2s, box-shadow 0.2s;
}

.back-to-top-link:hover {
    background: linear-gradient(90deg, #ffe082 0%, #ffd54f 100%);
    color: #222;
    box-shadow: 0 4px 16px rgba(0,0,0,0.13);
}

#canvas {
    display: flex;
    justify-content: center;
    align-items: flex-start;
    flex-direction: column;
    /* 余計な座標指定や高さ指定はしない */
    position: relative;
    z-index: 1;
}

#canvas-container {
    margin-bottom: 20px;
    /* 余計な座標指定や高さ指定はしない */
    position: relative;
    z-index: 10;
}

canvas {
    display: inline-block;
}

.quiz-container {
    text-align: center;
    background: #ffffff;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.1);
    width: 350px;
    /* ホバー時の変化を無効化 */
    transition: none;
    position: relative;
    z-index: 10;
}

/* ホバー時の変化を無効化 */
.quiz-container:hover {
    transform: none;
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.1);
}

.quiz-input, .quiz-button {
    all: unset;
    /* 既存の個別スタイルはこの下に再定義 */
}

.quiz-input {
    width: 100%;
    padding: 15px;
    margin-bottom: 15px;
    font-size: 16px;
    border: 1px solid #ddd;
    border-radius: 10px;
    box-sizing: border-box;
    transition: border-color 0.3s;
}

.quiz-input:focus {
    border-color: #007bff;
    outline: none;
}

.quiz-button {
    padding: 12px 25px;
    font-size: 16px;
    color: #fff;
    background-color: #007bff;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
}

.quiz-button:hover {
    background-color: #0056b3;
    transform: scale(1.05);
}

button {
    padding: 12px 25px;
    font-size: 16px;
    color: #fff;
    background-color: #007bff;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
}

button:hover {
    background-color: #0056b3;
    transform: scale(1.05);
}

@media (max-width: 600px) {
    body {
        padding: 20px;
    }

    #canvas-container {
        padding: 10px;
    }

    .quiz-container {
        width: 100%;
        padding: 20px;
    }

    .quiz-input, .quiz-button {
        font-size: 14px;
    }
}