:root {
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --text-color: #2c3e50;
    --background-color: #f4f6f7;
    --card-background: #ffffff;
    --hover-color: #2980b9;
}

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

body {
    font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, system-ui, Roboto, 'Helvetica Neue', 'Segoe UI', 'Apple SD Gothic Neo', 'Noto Sans KR', 'Malgun Gothic', sans-serif;
    background-color: var(--background-color);
    line-height: 1.6;
    color: var(--text-color);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    width: 95%;
    margin: 0 auto;
    padding: 2rem;
    flex-grow: 1;
}

/* Header Styles */
header {
    text-align: center;
    margin-bottom: 2rem;
    background-color: var(--card-background);
    border-radius: 15px;
    padding: 2rem;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.05);
}

.header-content h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.header-content .subtitle {
    color: #6c757d;
    margin-bottom: 1.5rem;
}

/* Search Container */
.search-container {
    display: flex;
    max-width: 500px;
    margin: 1.5rem auto;
    position: relative;
}

#searchInput {
    flex-grow: 1;
    padding: 0.75rem 1rem;
    border: 2px solid var(--primary-color);
    border-radius: 30px 0 0 30px;
    font-size: 1rem;
    transition: all 0.3s ease;
}

#searchInput:focus {
    outline: none;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

#searchButton {
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0 30px 30px 0;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

#searchButton:hover {
    background-color: var(--hover-color);
}

/* Category Filter */
.category-filter {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.filter-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background-color: #f1f3f5;
    border: none;
    border-radius: 30px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 0.9rem;
    color: #495057;
}

.filter-btn i {
    font-size: 1rem;
}

.filter-btn.active,
.filter-btn:hover {
    background-color: var(--primary-color);
    color: white;
    transform: scale(1.05);
}

/* Links Container */
.links-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1.5rem;
    padding: 1rem 0;
}

.link-item {
    background-color: var(--card-background);
    border-radius: 15px;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.link-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.1);
}

.link-item .category-tag {
    position: absolute;
    top: 0;
    left: 0;
    padding: 0.25rem 0.75rem;
    font-size: 0.7rem;
    font-weight: bold;
    text-transform: uppercase;
    border-bottom-right-radius: 10px;
}

.link-item .category-tag.portal { background-color: #a5d8ff; color: #1864ab; }
.link-item .category-tag.video { background-color: #b2f2bb; color: #2b8a3e; }
.link-item .category-tag.sns { background-color: #ffd8a8; color: #d9480f; }
.link-item .category-tag.ott { background-color: #c5f6fa; color: #0b7285; }

.link-item a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 600;
    margin-top: 1rem;
    font-size: 1.1rem;
    transition: color 0.3s ease;
}

.link-item a:hover {
    color: var(--primary-color);
}

.link-item .link-description {
    color: #6c757d;
    font-size: 0.9rem;
    margin-top: 0.5rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* No Results Message */
.no-results-message {
    text-align: center;
    padding: 2rem;
    background-color: var(--card-background);
    border-radius: 15px;
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.05);
}

.no-results-message i {
    font-size: 4rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

/* Footer */
footer {
    text-align: center;
    padding: 1.5rem;
    background-color: var(--card-background);
    margin-top: 2rem;
    color: #6c757d;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 1rem;
    }

    .header-content h1 {
        font-size: 2rem;
    }

    .category-filter {
        flex-direction: column;
        align-items: stretch;
    }

    .filter-btn {
        justify-content: center;
    }

    .links-container {
        grid-template-columns: 1fr;
    }

    .search-container {
        flex-direction: column;
    }

    #searchInput, 
    #searchButton {
        width: 100%;
        border-radius: 30px;
    }

    #searchButton {
        margin-top: 0.5rem;
    }
}

/* Accessibility and Print Styles */
@media print {
    body {
        background-color: white;
    }

    .container {
        max-width: none;
        width: 100%;
        padding: 0;
    }

    .category-filter,
    .search-container,
    footer {
        display: none;
    }
}