/* ==========================================
   Abfallfreie Zone - Zero Waste Blog
   Modern, Clean, Responsive Design
   ========================================== */

:root {
    --primary-green: #10B981;
    --dark-green: #059669;
    --light-green: #D1FAE5;
    --gray-50: #F9FAFB;
    --gray-100: #F3F4F6;
    --gray-200: #E5E7EB;
    --gray-300: #D1D5DB;
    --gray-600: #4B5563;
    --gray-700: #374151;
    --gray-900: #111827;
    --white: #FFFFFF;
    
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Poppins', sans-serif;
    
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
    
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-full: 9999px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    color: var(--gray-900);
    line-height: 1.7;
    background: var(--white);
}

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

/* ==========================================
   KI-Banner
   ========================================== */

.ki-banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 12px 20px;
    text-align: center;
    font-size: 14px;
    position: sticky;
    top: 0;
    z-index: 9999;
    box-shadow: var(--shadow-md);
}

.ki-banner a {
    color: white;
    text-decoration: underline;
    margin-left: 10px;
    font-weight: 600;
}

.ki-banner a:hover {
    opacity: 0.8;
}

/* ==========================================
   Header
   ========================================== */

.header {
    background: white;
    border-bottom: 1px solid var(--gray-200);
    position: sticky;
    top: 44px;
    z-index: 1000;
    box-shadow: var(--shadow-sm);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--gray-900);
    font-weight: 700;
    font-size: 20px;
    font-family: var(--font-heading);
}

.logo-icon {
    font-size: 28px;
}

.logo:hover {
    color: var(--primary-green);
}

.nav {
    display: flex;
    gap: 32px;
}

.nav-link {
    color: var(--gray-700);
    text-decoration: none;
    font-weight: 500;
    font-size: 15px;
    transition: color 0.2s;
    position: relative;
}

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

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -20px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-green);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--gray-900);
    transition: all 0.3s;
}

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

.hero {
    background: linear-gradient(135deg, var(--light-green) 0%, var(--gray-50) 100%);
    padding: 80px 0;
}

.hero-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 56px;
    font-weight: 800;
    line-height: 1.1;
    margin-bottom: 24px;
    color: var(--gray-900);
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary-green), var(--dark-green));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 20px;
    color: var(--gray-600);
    margin-bottom: 40px;
    line-height: 1.6;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 60px;
}

.hero-stats {
    display: flex;
    gap: 48px;
    justify-content: center;
}

.stat {
    text-align: center;
}

.stat-number {
    font-size: 48px;
    font-weight: 800;
    color: var(--primary-green);
    font-family: var(--font-heading);
}

.stat-label {
    font-size: 14px;
    color: var(--gray-600);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-top: 8px;
}

/* ==========================================
   Buttons
   ========================================== */

.btn {
    display: inline-block;
    padding: 14px 28px;
    border-radius: var(--radius-full);
    font-weight: 600;
    font-size: 15px;
    text-decoration: none;
    transition: all 0.3s;
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--primary-green);
    color: white;
}

.btn-primary:hover {
    background: var(--dark-green);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.btn-secondary {
    background: white;
    color: var(--gray-700);
    border: 2px solid var(--gray-300);
}

.btn-secondary:hover {
    border-color: var(--primary-green);
    color: var(--primary-green);
}

.btn-large {
    padding: 18px 36px;
    font-size: 16px;
}

/* ==========================================
   Sections
   ========================================== */

.section {
    padding: 80px 0;
}

.section-gray {
    background: var(--gray-50);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 48px;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 36px;
    font-weight: 700;
    color: var(--gray-900);
}

.text-center {
    text-align: center;
    margin-bottom: 48px;
}

.section-link {
    color: var(--primary-green);
    text-decoration: none;
    font-weight: 600;
    transition: transform 0.2s;
    display: inline-block;
}

.section-link:hover {
    transform: translateX(4px);
}

/* ==========================================
   Articles Grid
   ========================================== */

.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 32px;
}

.article-card {
    background: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    transition: all 0.3s;
    text-decoration: none;
    color: inherit;
    display: block;
}

.article-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.article-image {
    width: 100%;
    height: 220px;
    object-fit: cover;
    background: linear-gradient(135deg, var(--light-green), var(--gray-100));
}

.article-content {
    padding: 24px;
}

.article-category {
    display: inline-block;
    background: var(--light-green);
    color: var(--dark-green);
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.article-title {
    font-family: var(--font-heading);
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--gray-900);
    line-height: 1.3;
}

.article-excerpt {
    color: var(--gray-600);
    font-size: 15px;
    line-height: 1.6;
    margin-bottom: 16px;
}

.article-meta {
    display: flex;
    gap: 16px;
    font-size: 13px;
    color: var(--gray-500);
}

.article-card-skeleton {
    background: var(--gray-100);
    border-radius: var(--radius-lg);
    height: 400px;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* ==========================================
   Categories Grid
   ========================================== */

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 24px;
}

.category-card {
    background: white;
    padding: 32px;
    border-radius: var(--radius-lg);
    text-align: center;
    text-decoration: none;
    color: inherit;
    transition: all 0.3s;
    border: 2px solid var(--gray-200);
}

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

.category-icon {
    font-size: 48px;
    display: block;
    margin-bottom: 16px;
}

.category-card h3 {
    font-family: var(--font-heading);
    font-size: 20px;
    margin-bottom: 8px;
    color: var(--gray-900);
}

.category-card p {
    color: var(--gray-600);
    font-size: 14px;
}

/* ==========================================
   Features Grid
   ========================================== */

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 32px;
    margin-top: 48px;
}

.feature-card {
    text-align: center;
    padding: 32px 24px;
}

.feature-icon {
    font-size: 64px;
    margin-bottom: 16px;
}

.feature-card h3 {
    font-family: var(--font-heading);
    font-size: 22px;
    margin-bottom: 12px;
    color: var(--gray-900);
}

.feature-card p {
    color: var(--gray-600);
    line-height: 1.6;
}

/* ==========================================
   CTA Section
   ========================================== */

.section-cta {
    background: linear-gradient(135deg, var(--primary-green), var(--dark-green));
    color: white;
}

.cta-box {
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.cta-box h2 {
    font-family: var(--font-heading);
    font-size: 40px;
    margin-bottom: 16px;
}

.cta-box p {
    font-size: 18px;
    margin-bottom: 32px;
    opacity: 0.9;
}

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

.footer {
    background: var(--gray-900);
    color: var(--gray-300);
    padding: 60px 0 32px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 48px;
    margin-bottom: 48px;
}

.footer-section h3 {
    color: white;
    margin-bottom: 16px;
    font-family: var(--font-heading);
}

.footer-section h4 {
    color: white;
    margin-bottom: 16px;
    font-size: 16px;
    font-weight: 600;
}

.footer-section p {
    line-height: 1.7;
    margin-bottom: 12px;
}

.footer-tech {
    font-size: 13px;
    color: var(--gray-500);
}

.footer-section ul {
    list-style: none;
}

.footer-section li {
    margin-bottom: 10px;
}

.footer-section a {
    color: var(--gray-300);
    text-decoration: none;
    transition: color 0.2s;
}

.footer-section a:hover {
    color: var(--primary-green);
}

.footer-bottom {
    border-top: 1px solid var(--gray-700);
    padding-top: 24px;
    text-align: center;
    font-size: 14px;
    color: var(--gray-500);
}

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

@media (max-width: 968px) {
    .nav {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: 40px;
    }
    
    .hero-subtitle {
        font-size: 18px;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .hero-stats {
        flex-wrap: wrap;
        gap: 32px;
    }
    
    .articles-grid {
        grid-template-columns: 1fr;
    }
    
    .categories-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
    }
}

@media (max-width: 640px) {
    .hero {
        padding: 48px 0;
    }
    
    .hero-title {
        font-size: 32px;
    }
    
    .section {
        padding: 48px 0;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
    }
    
    .ki-banner {
        font-size: 12px;
        padding: 10px 15px;
    }
}