/* ================================
   Design System - Editorial Tech Magazine
   ================================ */

:root {
    /* Colors - Bold & Confident */
    --primary: #0066FF;
    --primary-dark: #0052CC;
    --accent: #FF3B5C;
    --success: #00D9A3;
    --warning: #FFB020;
    
    /* Neutrals - High Contrast */
    --gray-50: #FAFBFC;
    --gray-100: #F4F5F7;
    --gray-200: #E4E7EB;
    --gray-300: #CBD2D9;
    --gray-400: #9AA5B1;
    --gray-500: #7B8794;
    --gray-600: #616E7C;
    --gray-700: #52606D;
    --gray-800: #3E4C59;
    --gray-900: #1F2933;
    
    /* Typography */
    --font-display: 'Manrope', -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', 'Courier New', monospace;
    
    /* Spacing System */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-5: 1.5rem;
    --space-6: 2rem;
    --space-8: 3rem;
    --space-10: 4rem;
    --space-12: 6rem;
    
    /* Shadows & Effects */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    
    /* Animation */
    --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ================================
   Reset & Base
   ================================ */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-display);
    font-size: 16px;
    line-height: 1.6;
    color: var(--gray-900);
    background: var(--gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-6);
}

/* ================================
   Typography
   ================================ */

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    letter-spacing: -0.02em;
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
h2 { font-size: clamp(2rem, 4vw, 3rem); }
h3 { font-size: clamp(1.5rem, 3vw, 2rem); }

.gradient-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ================================
   Navigation
   ================================ */

.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--gray-200);
    animation: slideDown 0.3s ease-out;
}

@keyframes slideDown {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    text-decoration: none;
    font-weight: 800;
    font-size: 1.5rem;
    color: var(--gray-900);
    transition: var(--transition);
}

.logo:hover {
    transform: translateY(-2px);
}

.logo-icon {
    font-size: 1.8rem;
    color: var(--primary);
}

.logo-accent {
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: var(--space-6);
}

.nav-link {
    position: relative;
    text-decoration: none;
    color: var(--gray-700);
    font-weight: 600;
    font-size: 0.95rem;
    transition: var(--transition);
    padding: var(--space-2) 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: var(--transition);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-2);
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--gray-900);
    transition: var(--transition);
}

.mobile-menu {
    display: none;
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: white;
    border-bottom: 1px solid var(--gray-200);
    padding: var(--space-4);
    z-index: 999;
}

.mobile-menu.active {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    animation: slideDown 0.3s ease-out;
}

.mobile-link {
    padding: var(--space-3);
    text-decoration: none;
    color: var(--gray-700);
    font-weight: 600;
    border-radius: 8px;
    transition: var(--transition);
}

.mobile-link:hover {
    background: var(--gray-100);
    color: var(--primary);
}

/* ================================
   Hero Section
   ================================ */

.hero {
    position: relative;
    padding: var(--space-12) 0 var(--space-10);
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: 
        radial-gradient(circle at 20% 50%, rgba(0, 102, 255, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 30%, rgba(255, 59, 92, 0.06) 0%, transparent 50%);
    z-index: -1;
}

.hero-content {
    max-width: 900px;
    text-align: center;
    margin: 0 auto;
}

.hero-title {
    margin-bottom: var(--space-5);
    animation: fadeInUp 0.6s ease-out;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--gray-600);
    margin-bottom: var(--space-8);
    line-height: 1.7;
    animation: fadeInUp 0.6s ease-out 0.1s both;
}

.hero-cta {
    display: flex;
    gap: var(--space-4);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--space-8);
    animation: fadeInUp 0.6s ease-out 0.2s both;
}

.btn {
    display: inline-flex;
    align-items: center;
    padding: var(--space-4) var(--space-6);
    font-weight: 600;
    font-size: 1rem;
    text-decoration: none;
    border-radius: 12px;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--primary);
    color: white;
    box-shadow: 0 4px 14px rgba(0, 102, 255, 0.3);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 102, 255, 0.4);
}

.btn-secondary {
    background: white;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-secondary:hover {
    background: var(--primary);
    color: white;
    transform: translateY(-2px);
}

.hero-stats {
    display: flex;
    gap: var(--space-8);
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 0.6s ease-out 0.3s both;
}

.stat {
    text-align: center;
}

.stat-value {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
    margin-bottom: var(--space-2);
}

.stat-label {
    font-size: 0.9rem;
    color: var(--gray-600);
    font-weight: 500;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ================================
   Filter Bar
   ================================ */

.filter-bar {
    position: sticky;
    top: 70px;
    z-index: 100;
    background: white;
    border-bottom: 1px solid var(--gray-200);
    padding: var(--space-4) 0;
    box-shadow: var(--shadow-sm);
}

.filter-content {
    display: flex;
    gap: var(--space-4);
    align-items: center;
    flex-wrap: wrap;
}

.filter-search {
    flex: 1;
    min-width: 250px;
}

.search-input {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    border: 2px solid var(--gray-200);
    border-radius: 10px;
    font-family: var(--font-display);
    font-size: 0.95rem;
    transition: var(--transition);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(0, 102, 255, 0.1);
}

.filter-chips {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    position: relative;
}

.chip {
    padding: var(--space-2) var(--space-4);
    background: var(--gray-100);
    border: 2px solid transparent;
    border-radius: 20px;
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--gray-700);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
}

.chip:hover {
    background: var(--gray-200);
    transform: translateY(-1px);
}

.chip.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

.filter-dropdown {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    margin-top: var(--space-2);
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 12px;
    padding: var(--space-2);
    box-shadow: var(--shadow-lg);
    flex-direction: column;
    gap: var(--space-2);
    min-width: 200px;
    z-index: 10;
}

.filter-dropdown.active {
    display: flex;
}

/* ================================
   Main Content Sections
   ================================ */

.main-content {
    padding: var(--space-10) 0;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-6);
}

.section-title {
    font-size: 2rem;
    color: var(--gray-900);
}

.section-link {
    color: var(--primary);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
}

.section-link:hover {
    transform: translateX(5px);
}

/* Featured Section */
.featured-section {
    margin-bottom: var(--space-10);
}

.featured-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--space-6);
}

.featured-card {
    position: relative;
    padding: var(--space-6);
    background: white;
    border: 2px solid var(--gray-200);
    border-radius: 16px;
    text-decoration: none;
    color: var(--gray-900);
    transition: var(--transition);
    overflow: hidden;
}

.featured-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    transform: scaleX(0);
    transform-origin: left;
    transition: var(--transition);
}

.featured-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.featured-card:hover::before {
    transform: scaleX(1);
}

.featured-icon {
    font-size: 3rem;
    margin-bottom: var(--space-4);
}

.featured-card h3 {
    font-size: 1.5rem;
    margin-bottom: var(--space-3);
}

.featured-card p {
    color: var(--gray-600);
    margin-bottom: var(--space-4);
}

.featured-badge {
    display: inline-block;
    padding: var(--space-1) var(--space-3);
    background: var(--gray-100);
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--gray-700);
}

/* Resources Section */
.resources-section {
    margin-bottom: var(--space-10);
}

.view-toggle {
    display: flex;
    gap: var(--space-2);
    background: var(--gray-100);
    padding: var(--space-1);
    border-radius: 10px;
}

.view-btn {
    padding: var(--space-2);
    background: transparent;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    color: var(--gray-600);
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.view-btn.active {
    background: white;
    color: var(--primary);
    box-shadow: var(--shadow-sm);
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--space-5);
}

.resource-card {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 12px;
    padding: var(--space-5);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

.resource-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.resource-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--space-3);
    gap: var(--space-3);
}

.resource-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--gray-900);
    flex: 1;
}

.category-badge {
    padding: var(--space-1) var(--space-2);
    background: var(--primary);
    color: white;
    border-radius: 6px;
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    white-space: nowrap;
}

.resource-description {
    color: var(--gray-600);
    margin-bottom: var(--space-4);
    line-height: 1.6;
    flex: 1;
}

.resource-meta {
    display: flex;
    gap: var(--space-2);
    flex-wrap: wrap;
    margin-bottom: var(--space-4);
}

.meta-tag {
    padding: var(--space-1) var(--space-2);
    background: var(--gray-100);
    border-radius: 6px;
    font-size: 0.8rem;
    color: var(--gray-700);
    font-weight: 500;
}

.resource-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-3) var(--space-4);
    background: var(--gray-900);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.9rem;
    transition: var(--transition);
}

.resource-link:hover {
    background: var(--primary);
    transform: translateY(-1px);
}

/* Loading & Empty States */
.loading-spinner {
    text-align: center;
    padding: var(--space-10);
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--gray-200);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin: 0 auto var(--space-4);
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.no-results {
    text-align: center;
    padding: var(--space-10);
}

.no-results-icon {
    font-size: 4rem;
    margin-bottom: var(--space-4);
    opacity: 0.5;
}

/* Category Overview */
.category-overview {
    margin-bottom: var(--space-10);
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--space-5);
}

.category-card {
    padding: var(--space-5);
    background: white;
    border: 2px solid var(--gray-200);
    border-radius: 12px;
    cursor: pointer;
    transition: var(--transition);
}

.category-card:hover {
    border-color: var(--primary);
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
}

.category-header {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    margin-bottom: var(--space-3);
}

.category-icon {
    font-size: 2rem;
}

.category-card h3 {
    font-size: 1.3rem;
    color: var(--gray-900);
}

.category-card p {
    color: var(--gray-600);
    margin-bottom: var(--space-4);
    line-height: 1.6;
}

.category-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.resource-count {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--primary);
}

/* ================================
   Footer
   ================================ */

.footer {
    background: var(--gray-900);
    color: white;
    padding: var(--space-10) 0 var(--space-6);
    margin-top: var(--space-12);
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr repeat(3, 1fr);
    gap: var(--space-8);
    margin-bottom: var(--space-8);
}

.footer-col h4 {
    margin-bottom: var(--space-4);
    font-size: 1rem;
}

.footer-col a {
    display: block;
    color: var(--gray-400);
    text-decoration: none;
    margin-bottom: var(--space-2);
    transition: var(--transition);
}

.footer-col a:hover {
    color: white;
    transform: translateX(3px);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-weight: 800;
    font-size: 1.5rem;
    margin-bottom: var(--space-4);
}

.footer-desc {
    color: var(--gray-400);
    line-height: 1.7;
}

.footer-bottom {
    text-align: center;
    padding-top: var(--space-6);
    border-top: 1px solid var(--gray-700);
    color: var(--gray-500);
}

/* ================================
   Responsive Design
   ================================ */

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero {
        padding: var(--space-8) 0 var(--space-6);
    }
    
    .hero-cta {
        flex-direction: column;
    }
    
    .hero-stats {
        gap: var(--space-6);
    }
    
    .filter-content {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-search {
        width: 100%;
    }
    
    .resources-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--space-6);
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-3);
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 var(--space-4);
    }
    
    h1 { font-size: 2rem; }
    h2 { font-size: 1.5rem; }
    
    .featured-grid {
        grid-template-columns: 1fr;
    }
}