/* ============================================
   Euclides - Dicionário de Matemática para Física
   Estilos Principais
   ============================================ */

/* ===== RESET & BASE ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Cores Principais */
    --primary: #3B82F6;
    --primary-dark: #2563EB;
    --primary-light: #60A5FA;
    --secondary: #10B981;
    --accent: #F59E0B;
    --purple: #8B5CF6;
    
    /* Cores de Fundo */
    --bg-dark: #0F172A;
    --bg-darker: #020617;
    --bg-card: rgba(30, 41, 59, 0.6);
    --bg-card-hover: rgba(51, 65, 85, 0.7);
    
    /* Gradientes */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-secondary: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-blue: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --gradient-green: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #f093fb 100%);
    
    /* Texto */
    --text-primary: #F1F5F9;
    --text-secondary: #CBD5E1;
    --text-muted: #94A3B8;
    
    /* Sombras */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.3);
    --shadow-glow: 0 0 20px rgba(59, 130, 246, 0.3);
    
    /* Transições */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s ease;
    
    /* Espaçamentos */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Tipografia */
    --font-heading: 'Poppins', sans-serif;
    --font-body: 'Inter', sans-serif;
}

body {
    font-family: var(--font-body);
    background: var(--bg-darker);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ===== HEADER ===== */
.header {
    padding: var(--spacing-lg) 0;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    text-align: center;
}

.logo {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: 0.5rem;
}

.logo-icon {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: 3rem;
}

.logo-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.tagline {
    color: var(--text-secondary);
    font-size: 1rem;
}

/* Header Minimal (para páginas de conceito) */
.header-minimal {
    padding: var(--spacing-md) 0;
}

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

.back-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
    text-decoration: none;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: var(--transition);
}

.back-link:hover {
    background: var(--bg-card);
    color: var(--primary-light);
}

.logo-small {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.logo-small .logo-icon {
    font-size: 2rem;
}

/* ===== HERO SECTION ===== */
.hero {
    position: relative;
    padding: var(--spacing-xl) 0;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-hero);
    opacity: 0.1;
    z-index: -1;
}

.hero-background::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.1) 0%, transparent 70%);
    animation: pulse 10s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 0.1; }
    50% { transform: scale(1.1); opacity: 0.2; }
}

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

.hero-title {
    font-family: var(--font-heading);
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    line-height: 1.2;
}

.highlight {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
}

/* Quick Links */
.quick-links {
    margin-top: var(--spacing-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.quick-links-label {
    color: var(--text-muted);
    font-size: 0.9rem;
}

.quick-link {
    background: var(--bg-card);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-secondary);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9rem;
    font-family: var(--font-body);
    transition: var(--transition);
}

.quick-link:hover {
    background: var(--bg-card-hover);
    border-color: var(--primary);
    color: var(--primary-light);
    transform: translateY(-2px);
}

/* ===== SECTIONS ===== */
.categories-section,
.featured-section,
.recent-section {
    padding: var(--spacing-xl) 0;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.title-icon {
    font-size: 2.5rem;
}

/* ===== CATEGORIES GRID ===== */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.category-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: var(--spacing-lg);
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
    opacity: 0;
    transition: var(--transition);
}

.category-card:hover {
    transform: translateY(-8px);
    border-color: var(--primary);
    box-shadow: var(--shadow-glow);
}

.category-card:hover::before {
    opacity: 1;
}

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

.category-icon {
    font-size: 2.5rem;
}

.category-name {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 600;
}

.category-description {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
    font-size: 0.95rem;
}

.category-count {
    color: var(--text-muted);
    font-size: 0.85rem;
}

/* ===== CONCEPTS GRID ===== */
.concepts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-md);
}

.concept-card {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: var(--spacing-md);
    text-decoration: none;
    color: var(--text-primary);
    transition: var(--transition);
    display: flex;
    flex-direction: column;
}

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

.concept-card-category {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 500;
    margin-bottom: var(--spacing-sm);
    background: var(--primary);
    color: white;
}

.concept-card-title {
    font-family: var(--font-heading);
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.concept-card-excerpt {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ===== FEATURED CONCEPT ===== */
.featured-concept {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    padding: var(--spacing-xl);
    position: relative;
    overflow: hidden;
}

.featured-concept::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 6px;
    background: var(--gradient-primary);
}

/* ===== FOOTER ===== */
.footer {
    background: rgba(15, 23, 42, 0.8);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding: var(--spacing-xl) 0;
    margin-top: var(--spacing-xl);
    text-align: center;
}

.footer-text {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.footer-subtext {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* ===== CONCEPT PAGE ===== */
.concept-page {
    padding: var(--spacing-xl) 0;
    min-height: 60vh;
}

.concept-loading,
.concept-error {
    text-align: center;
    padding: var(--spacing-xl);
}

.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid rgba(255, 255, 255, 0.1);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

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

.error-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-md);
}

.concept-header {
    margin-bottom: var(--spacing-xl);
}

.concept-category-badge {
    display: inline-block;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: var(--spacing-md);
    background: var(--primary);
    color: white;
}

.concept-title {
    font-family: var(--font-heading);
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.concept-section {
    background: var(--bg-card);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 16px;
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-lg);
}

.concept-section-title {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: var(--spacing-md);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.section-icon {
    font-size: 1.75rem;
}

.concept-text {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.concept-highlight {
    background: linear-gradient(90deg, rgba(59, 130, 246, 0.1) 0%, rgba(139, 92, 246, 0.1) 100%);
    border-left: 4px solid var(--primary);
    padding: var(--spacing-md);
    border-radius: 8px;
}

.concept-analogia {
    background: linear-gradient(90deg, rgba(245, 158, 11, 0.1) 0%, rgba(239, 68, 68, 0.1) 100%);
    border-left: 4px solid var(--accent);
    padding: var(--spacing-md);
    border-radius: 8px;
}

.math-notation {
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    padding: var(--spacing-md);
    font-family: 'Courier New', monospace;
    font-size: 1.2rem;
    color: var(--primary-light);
    white-space: pre-wrap;
    overflow-x: auto;
}

.examples-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.example-item {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: var(--spacing-md);
}

.example-title {
    font-weight: 600;
    color: var(--primary-light);
    margin-bottom: 0.5rem;
}

.example-description {
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.example-formula {
    background: rgba(0, 0, 0, 0.3);
    border-radius: 8px;
    padding: var(--spacing-sm);
    font-family: 'Courier New', monospace;
    color: var(--secondary);
    white-space: pre-wrap;
    overflow-x: auto;
}

.related-concepts {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-sm);
}

.related-concept-link {
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    padding: var(--spacing-sm);
    text-decoration: none;
    color: var(--text-primary);
    display: block;
    transition: var(--transition);
}

.related-concept-link:hover {
    background: rgba(59, 130, 246, 0.1);
    border-color: var(--primary);
    transform: translateX(4px);
}

.related-concept-name {
    font-weight: 500;
    color: var(--primary-light);
}

.related-concept-type {
    font-size: 0.85rem;
    color: var(--text-muted);
    text-transform: capitalize;
}

/* Buttons */
.btn-primary {
    display: inline-block;
    background: var(--gradient-primary);
    color: white;
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .concept-title {
        font-size: 2rem;
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
    }
    
    .concepts-grid {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
}