/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --color-white: #ffffff;
    --color-black: #212529;
    --color-gray-50: #f8f9fa;
    --color-gray-100: #f1f3f5;
    --color-gray-200: #e9ecef;
    --color-gray-300: #dee2e6;
    --color-gray-400: #ced4da;
    --color-gray-500: #adb5bd;
    --color-gray-600: #868e96;
    --color-gray-700: #495057;
    --color-gray-800: #343a40;
    --color-gray-900: #212529;
    
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;
    
    --border-radius-sm: 0.5rem;
    --border-radius-md: 0.75rem;
    --border-radius-lg: 1rem;
    --border-radius-full: 9999px;
    
    --transition-fast: 200ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background-color: var(--color-white);
    color: var(--color-gray-900);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-gray-200);
    z-index: 1000;
    transition: box-shadow var(--transition-base);
}

.header.scrolled {
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.5rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
    transition: transform var(--transition-fast);
}

.logo:hover {
    transform: scale(1.02);
}

.logo-icon {
    width: 2.5rem;
    height: 2.5rem;
    background-color: var(--color-gray-900);
    color: var(--color-white);
    border-radius: var(--border-radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.125rem;
}

.logo-text {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-gray-900);
    letter-spacing: -0.02em;
}

.nav-desktop {
    display: none;
    gap: 2rem;
}

.nav-link {
    color: var(--color-gray-700);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-fast);
}

.nav-link:hover {
    color: var(--color-gray-900);
}

.search-bar {
    display: none;
    position: relative;
}

.search-input {
    width: 16rem;
    padding: 0.625rem 1rem 0.625rem 2.5rem;
    background-color: var(--color-gray-50);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--border-radius-full);
    font-size: 0.875rem;
    transition: border-color var(--transition-fast);
}

.search-input:focus {
    outline: none;
    border-color: var(--color-gray-400);
}

.search-icon {
    position: absolute;
    left: 0.75rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-gray-400);
}

.mobile-menu-btn {
    display: block;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.menu-icon {
    display: block;
    width: 1.5rem;
    height: 2px;
    background-color: var(--color-gray-700);
    position: relative;
}

.menu-icon::before,
.menu-icon::after {
    content: '';
    display: block;
    width: 1.5rem;
    height: 2px;
    background-color: var(--color-gray-700);
    position: absolute;
    transition: transform var(--transition-fast);
}

.menu-icon::before {
    top: -0.5rem;
}

.menu-icon::after {
    bottom: -0.5rem;
}

.mobile-menu-btn.active .menu-icon {
    background-color: transparent;
}

.mobile-menu-btn.active .menu-icon::before {
    transform: rotate(45deg);
    top: 0;
}

.mobile-menu-btn.active .menu-icon::after {
    transform: rotate(-45deg);
    bottom: 0;
}

.mobile-menu {
    display: none;
    flex-direction: column;
    gap: 1rem;
    padding-bottom: 1.5rem;
}

.mobile-menu.active {
    display: flex;
    animation: slideDown 0.3s ease;
}

.mobile-nav-link {
    color: var(--color-gray-700);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 0;
    transition: color var(--transition-fast);
}

.mobile-nav-link:hover {
    color: var(--color-gray-900);
}

.mobile-search {
    position: relative;
    margin-top: 0.5rem;
}

/* Hero Section */
.hero {
    padding: 10rem 0 6rem;
    background: linear-gradient(to bottom, var(--color-gray-50), var(--color-white));
    margin-top: 5rem;
}

.hero-content {
    max-width: 48rem;
    margin: 0 auto;
    text-align: center;
    animation: fadeIn 0.6s ease;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-gray-900);
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin-bottom: 1.5rem;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-gray-600);
    line-height: 1.6;
}

/* Categories Filter */
.categories-filter {
    position: sticky;
    top: 5rem;
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-gray-200);
    padding: 1.5rem 0;
    z-index: 100;
}

.category-buttons {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    justify-content: center;
}

.category-btn {
    padding: 0.5rem 1.5rem;
    border-radius: var(--border-radius-full);
    border: none;
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    background-color: var(--color-gray-100);
    color: var(--color-gray-700);
}

.category-btn:hover {
    background-color: var(--color-gray-200);
}

.category-btn.active {
    background-color: var(--color-gray-900);
    color: var(--color-white);
}

/* Search Results */
.search-results {
    margin-top: 3rem;
}

.search-results.hidden {
    display: none;
}

.search-results-box {
    background-color: var(--color-gray-50);
    border-radius: var(--border-radius-md);
    padding: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
}

.clear-search-btn {
    background: none;
    border: none;
    color: var(--color-gray-600);
    text-decoration: underline;
    cursor: pointer;
    font-size: 0.875rem;
}

.clear-search-btn:hover {
    color: var(--color-gray-900);
}

/* Articles Section */
.articles-section {
    padding: 4rem 0 6rem;
}

.articles-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 3rem;
    margin-bottom: 4rem;
}

.article-card {
    animation: slideUp 0.6s ease;
}

.article-link {
    text-decoration: none;
    color: inherit;
    display: block;
}

.article-image {
    position: relative;
    overflow: hidden;
    border-radius: var(--border-radius-md);
    aspect-ratio: 16 / 9;
    background-color: var(--color-gray-100);
    margin-bottom: 1.5rem;
}

.article-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.article-card:hover .article-image img {
    transform: scale(1.05);
}

.article-content {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.article-category {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--color-gray-700);
    background-color: var(--color-gray-100);
    border-radius: var(--border-radius-full);
    width: fit-content;
}

.article-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-gray-900);
    line-height: 1.3;
    transition: color var(--transition-fast);
}

.article-card:hover .article-title {
    color: var(--color-gray-700);
}

.article-excerpt {
    color: var(--color-gray-600);
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-meta {
    display: flex;
    gap: 1rem;
    font-size: 0.875rem;
    color: var(--color-gray-500);
    padding-top: 0.5rem;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.375rem;
}

.meta-item svg {
    flex-shrink: 0;
}

/* Pagination */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0.5rem;
}

.pagination-btn {
    padding: 0.5rem;
    border: 1px solid var(--color-gray-200);
    background-color: var(--color-white);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.pagination-btn:hover:not(:disabled) {
    background-color: var(--color-gray-50);
}

.pagination-btn:disabled {
    opacity: 0.3;
    cursor: not-allowed;
}

.page-number {
    min-width: 2.5rem;
    height: 2.5rem;
    border: 1px solid var(--color-gray-200);
    background-color: var(--color-white);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    font-weight: 500;
    transition: all var(--transition-fast);
}

.page-number:hover {
    background-color: var(--color-gray-50);
}

.page-number.active {
    background-color: var(--color-gray-900);
    color: var(--color-white);
    border-color: var(--color-gray-900);
}

/* Footer */
.footer {
    background-color: var(--color-gray-50);
    border-top: 1px solid var(--color-gray-200);
    margin-top: 8rem;
    padding: 4rem 0 2rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-brand .logo {
    margin-bottom: 1rem;
}

.footer-description {
    color: var(--color-gray-600);
    line-height: 1.6;
    max-width: 32rem;
}

.footer-links h3,
.footer-categories h3 {
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-gray-900);
    margin-bottom: 1rem;
}

.footer-links ul,
.footer-categories ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.footer-links a {
    color: var(--color-gray-600);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-gray-900);
}

.footer-categories li {
    color: var(--color-gray-600);
    font-size: 0.875rem;
}

.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid var(--color-gray-200);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
}

.copyright {
    color: var(--color-gray-600);
    font-size: 0.875rem;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-link {
    width: 2.5rem;
    height: 2.5rem;
    border: 1px solid var(--color-gray-200);
    background-color: var(--color-white);
    border-radius: var(--border-radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--color-gray-600);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.social-link:hover {
    color: var(--color-gray-900);
    border-color: var(--color-gray-400);
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes slideUp {
    from {
        transform: translateY(20px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes slideDown {
    from {
        transform: translateY(-10px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* Responsive Design */
@media (min-width: 768px) {
    .hero-title {
        font-size: 3.75rem;
    }
    
    .articles-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: 2fr 1fr 1fr;
    }
    
    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
}

@media (min-width: 1024px) {
    .nav-desktop {
        display: flex;
    }
    
    .search-bar {
        display: block;
    }
    
    .mobile-menu-btn {
        display: none;
    }
    
    .articles-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* Utility Classes */
.hidden {
    display: none !important;
}