body {
    margin: 0;
    padding: 0;
    background: #f4f6f9;
    font-family:
        "Yu Gothic",
        "Meiryo",
        sans-serif;
}

.error-container {
    max-width: 600px;
    margin: 50px auto;
    padding: 24px;
    background: #ffffff;
    border-radius: 8px;
    box-shadow:
        0 2px 8px rgba(0,0,0,0.1);
    text-align: center;
}

.error-code {
    font-size: 48px;
    font-weight: bold;
    color: #dc3545;
    margin-bottom: 16px;
}

.error-title {
    font-size: 24px;
    margin-bottom: 16px;
}

.error-message {
    font-size: 16px;
    line-height: 1.8;
    word-break: break-word;
}

@media (max-width: 768px) {

    .error-container {
        margin: 20px;
        padding: 20px;
    }

    .error-code {
        font-size: 36px;
    }

    .error-title {
        font-size: 20px;
    }

    .error-message {
        font-size: 15px;
    }
}