/* 404.css */

.error-content {
    text-align: center;
    padding: 60px 20px;
}

.illustration-box {
    width: 200px;
    height: 200px;
    margin: 0 auto 20px;
}

.error-code {
    font-family: 'Google Sans', sans-serif;
    font-size: 6rem;
    color: #000000; /* 主張しすぎない薄いグレー */
    margin: 0;
    font-weight: 700;
    letter-spacing: -2px;
}

.error-message {
    font-size: 2rem;
    color: #000000;
    margin-bottom: 15px;
}

.error-description {
    color: #000000;
    font-size: 1rem;
    line-height: 1.6;
    margin-bottom: 40px;
}

/* 戻るボタンをGoogle Blueに */
.back-btn {
    display: inline-block;
    background-color: #1A73E8;
    color: #ffffff;
    text-decoration: none;
    padding: 16px 40px;
    border-radius: 30px;
    font-weight: bold;
    font-size: 1.1rem;
    box-shadow: 0 4px 12px rgba(26, 115, 232, 0.2);
    transition: all 0.2s ease;
}

.back-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(26, 115, 232, 0.3);
    background-color: #1765cc;
}

/* スマホ版 */
@media (max-width: 600px) {
    .error-code { font-size: 4.5rem; }
    .error-message { font-size: 1.5rem; }
}