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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: #f8f9fa;
    min-height: 100vh;
    padding: 0;
    border-top: 8px solid #2563eb;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    text-align: center;
    color: #2563eb;
    margin-bottom: 50px;
    padding: 40px 20px;
}

header h1 {
    font-size: 4rem;
    margin-bottom: 10px;
    text-shadow: none;
    font-family: 'Trebuchet MS', sans-serif;
}

header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* 검색 및 필터 섹션 */
.search-section {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-bottom: 40px;
    padding: 25px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.search-box {
    width: 100%;
    padding: 12px 20px;
    font-size: 1rem;
    border: 2px solid #2563eb;
    border-radius: 10px;
    outline: none;
    transition: all 0.3s;
}

.search-box:focus {
    box-shadow: 0 0 10px rgba(37, 99, 235, 0.3);
    border-color: #1d4ed8;
}

.search-box::placeholder {
    color: #999;
}

.filter-buttons {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    justify-content: center;
}

.filter-btn {
    padding: 10px 20px;
    font-size: 0.95rem;
    border: 2px solid #2563eb;
    background: transparent;
    color: #2563eb;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 500;
}

.filter-btn:hover {
    background: #e0e7ff;
    transform: translateY(-2px);
}

.filter-btn.active {
    background: #2563eb;
    color: white;
}

.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-bottom: 50px;
}

/* 카드 링크 스타일 */
.card-link {
    text-decoration: none;
    transition: transform 0.3s;
}

.card-link:hover {
    transform: translateY(-10px);
}

.card {
    width: 100%;
    height: 470px;
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    overflow: hidden;
    cursor: pointer;
    transition: all 0.3s;
}

.card:hover {
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
}

.card-front {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #2563eb 0%, #3b82f6 100%);
    color: white;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.card-image {
    width: 120px;
    height: 120px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    margin-bottom: 20px;
    object-fit: cover;
}

.card-front h3 {
    font-size: 1.5rem;
    text-align: center;
}

/* 반응형 디자인 */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    header p {
        font-size: 1rem;
    }

    .search-section {
        padding: 20px;
    }

    .filter-buttons {
        justify-content: flex-start;
        gap: 10px;
    }

    .filter-btn {
        padding: 8px 16px;
        font-size: 0.9rem;
    }

    .cards-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .card {
        height: 300px;
    }
}