/* Professional Landing Page Redesign */

/* Hero Section - Clean & Professional */
.hero {
    position: relative;
    min-height: 75vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
    padding: 6rem 2rem 4rem;
    overflow: hidden;
}

[data-theme="dark"] .hero {
    background: linear-gradient(180deg, #0f172a 0%, #1e293b 100%);
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    opacity: 0.03;
    background-image:
        linear-gradient(30deg, #667eea 12%, transparent 12.5%, transparent 87%, #667eea 87.5%, #667eea),
        linear-gradient(150deg, #667eea 12%, transparent 12.5%, transparent 87%, #667eea 87.5%, #667eea),
        linear-gradient(30deg, #667eea 12%, transparent 12.5%, transparent 87%, #667eea 87.5%, #667eea),
        linear-gradient(150deg, #667eea 12%, transparent 12.5%, transparent 87%, #667eea 87.5%, #667eea);
    background-size: 80px 140px;
    background-position: 0 0, 0 0, 40px 70px, 40px 70px;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 900px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1.25rem;
    background: var(--surface-light);
    border: 1px solid var(--border-color);
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 600;
    color: #667eea;
    margin-bottom: 2rem;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.1);
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 800;
    margin-bottom: 1.5rem;
    line-height: 1.15;
    color: var(--text-main);
    letter-spacing: -0.02em;
}

.gradient-text {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: inline-block;
}

.hero-subtitle {
    font-size: clamp(1.1rem, 2vw, 1.35rem);
    max-width: 650px;
    margin: 0 auto 3rem;
    color: var(--text-muted);
    line-height: 1.7;
    font-weight: 400;
}

.hero-cta {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 4rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.75rem;
    border-radius: 10px;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-decoration: none;
    border: 2px solid transparent;
    cursor: pointer;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 14px rgba(102, 126, 234, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: var(--surface-light);
    color: var(--text-main);
    border-color: var(--border-color);
}

.btn-secondary:hover {
    border-color: #667eea;
    background: var(--bg-secondary);
    transform: translateY(-2px);
}

/* Stats Grid - Minimalist */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 2rem;
    max-width: 700px;
    margin: 0 auto;
    padding: 2rem 0;
}

.stat-card {
    text-align: center;
    padding: 1.5rem 1rem;
    background: transparent;
    border-radius: 12px;
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-3px);
}

.stat-number {
    font-size: 2.25rem;
    font-weight: 800;
    margin-bottom: 0.25rem;
    color: #667eea;
    line-height: 1;
}

.stat-label {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

/* Featured Topics - Card Grid */
.featured-topics {
    padding: 5rem 0;
    background: var(--bg-main);
}

.section-title {
    text-align: center;
    font-size: 2.25rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
    color: var(--text-main);
    letter-spacing: -0.02em;
}

.section-subtitle {
    text-align: center;
    font-size: 1.1rem;
    color: var(--text-muted);
    margin-bottom: 3rem;
    font-weight: 400;
}

.topics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 3rem;
}

.topic-card {
    display: flex;
    align-items: center;
    gap: 1.25rem;
    padding: 1.75rem;
    background: var(--surface-light);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.topic-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transform: scaleY(0);
    transition: transform 0.3s ease;
}

.topic-card:hover::before {
    transform: scaleY(1);
}

.topic-card:hover {
    transform: translateX(4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    border-color: #667eea;
}

.topic-icon {
    font-size: 2.5rem;
    flex-shrink: 0;
    filter: grayscale(0.2);
}

.topic-info {
    flex: 1;
}

.topic-name {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 0.25rem;
    display: block;
}

.topic-count {
    font-size: 0.875rem;
    color: var(--text-muted);
    font-weight: 500;
}

/* Articles Section */
#articles {
    padding-top: 5rem;
}

/* Improved Search Container */
.search-filter-container {
    background: var(--surface-light);
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid var(--border-color);
    margin-bottom: 3rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.04);
}

/* Dark Mode Enhancements */
[data-theme="dark"] .hero-badge {
    background: var(--bg-secondary);
    border-color: var(--border-color);
}

[data-theme="dark"] .btn-secondary {
    background: var(--bg-secondary);
}

[data-theme="dark"] .topic-card {
    background: var(--bg-secondary);
}

[data-theme="dark"] .search-filter-container {
    background: var(--bg-secondary);
}

/* Responsive Design */
@media (max-width: 768px) {
    .hero {
        min-height: 65vh;
        padding: 4rem 1.5rem 3rem;
    }

    .hero-title {
        font-size: 2.25rem;
    }

    .hero-subtitle {
        font-size: 1.05rem;
    }

    .hero-cta {
        flex-direction: column;
        align-items: stretch;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .stat-number {
        font-size: 2rem;
    }

    .topics-grid {
        grid-template-columns: 1fr;
    }

    .featured-topics {
        padding: 3rem 0;
    }

    .section-title {
        font-size: 1.875rem;
    }
}

@media (max-width: 480px) {
    .stats-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .topic-card {
        padding: 1.5rem;
    }
}

/* Smooth Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-content>* {
    animation: fadeInUp 0.6s ease-out backwards;
}

.hero-badge {
    animation-delay: 0.1s;
}

.hero-title {
    animation-delay: 0.2s;
}

.hero-subtitle {
    animation-delay: 0.3s;
}

.hero-cta {
    animation-delay: 0.4s;
}

.stats-grid {
    animation-delay: 0.5s;
}