/* 404エラーページ専用スタイル */
.error-404 {
    min-height: 60vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 40px 20px;
}

.error-404 h1 {
    font-size: 120px;
    color: #28a745;
    margin: 0;
    font-weight: bold;
    line-height: 1;
}

.error-404 h2 {
    font-size: 32px;
    color: #333;
    margin: 20px 0;
}

.error-404 p {
    font-size: 18px;
    color: #666;
    margin: 20px 0 40px;
    max-width: 600px;
}

.back-to-home {
    display: inline-block;
    background: linear-gradient(135deg, #28a745, #218838);
    color: white;
    padding: 15px 40px;
    border-radius: 50px;
    text-decoration: none;
    font-size: 18px;
    font-weight: bold;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(40, 167, 69, 0.3);
}

.back-to-home:hover {
    background: linear-gradient(135deg, #218838, #1e7e34);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(40, 167, 69, 0.4);
}

.back-to-home i {
    margin-right: 8px;
}

.helpful-links {
    margin-top: 60px;
    padding-top: 40px;
    border-top: 1px solid #e9ecef;
    width: 100%;
    max-width: 800px;
}

.helpful-links h3 {
    font-size: 24px;
    color: #333;
    margin-bottom: 20px;
}

.links-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-top: 20px;
}

.link-item {
    text-align: left;
}

.link-item a {
    color: #28a745;
    text-decoration: none;
    font-size: 16px;
    display: inline-flex;
    align-items: center;
    transition: color 0.3s ease;
}

.link-item a:hover {
    color: #218838;
    text-decoration: underline;
}

.link-item a::before {
    content: "→";
    margin-right: 8px;
}