/* ==========================================
   TrigMaster - Learn Trigonometry
   Beautiful, Modern CSS Styles
   ========================================== */

/* CSS Variables - Design System */
:root {
    /* Colors - Educational App Palette */
    --primary: #4F46E5;
    --primary-light: #818CF8;
    --primary-dark: #3730A3;
    --secondary: #06B6D4;
    --secondary-light: #22D3EE;
    --accent: #F97316;
    --accent-light: #FB923C;

    /* Trig function colors */
    --sin-color: #EC4899;
    --cos-color: #3B82F6;
    --tan-color: #10B981;

    /* Neutrals */
    --bg-primary: #F8FAFC;
    --bg-secondary: #EEF2FF;
    --bg-card: #FFFFFF;
    --text-primary: #1E293B;
    --text-secondary: #64748B;
    --text-muted: #94A3B8;
    --border-color: #E2E8F0;

    /* Difficulty colors */
    --beginner: #10B981;
    --intermediate: #F59E0B;
    --advanced: #EF4444;

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;

    /* Border radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;

    /* Fonts */
    --font-sans: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', ui-monospace, monospace;
}

/* Reset & Base Styles */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-primary);
}

h1 { font-size: clamp(2.5rem, 5vw, 4rem); }
h2 { font-size: clamp(1.75rem, 4vw, 2.5rem); }
h3 { font-size: clamp(1.25rem, 3vw, 1.5rem); }
h4 { font-size: 1.125rem; }

p {
    color: var(--text-secondary);
}

a {
    color: var(--primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-dark);
}

/* Layout */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

.section {
    padding: var(--space-3xl) 0;
}

/* ==========================================
   Navigation
   ========================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    transition: all var(--transition-normal);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-md) var(--space-lg);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--primary);
}

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

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.nav-link {
    font-weight: 500;
    color: var(--text-secondary);
    position: relative;
    padding: var(--space-xs) 0;
}

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

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

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

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

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: all var(--transition-fast);
}

@media (max-width: 768px) {
    .nav-links {
        display: none;
    }

    .mobile-menu-btn {
        display: flex;
    }
}

/* ==========================================
   Hero Section
   ========================================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding-top: 80px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

#hero-canvas {
    width: 100%;
    height: 100%;
    opacity: 0.4;
}

.hero-content {
    position: relative;
    z-index: 1;
    text-align: center;
    max-width: 800px;
    padding: var(--space-xl);
}

.hero h1 {
    margin-bottom: var(--space-lg);
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 50%, var(--accent) 100%);
    -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(--space-xl);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-buttons {
    display: flex;
    gap: var(--space-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--space-2xl);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-md) var(--space-xl);
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--radius-lg);
    border: none;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    box-shadow: 0 4px 14px rgba(79, 70, 229, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(79, 70, 229, 0.5);
    color: white;
}

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

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

.hero-stats {
    display: flex;
    gap: var(--space-2xl);
    justify-content: center;
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary);
}

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

/* ==========================================
   Section Header
   ========================================== */
.section-header {
    text-align: center;
    max-width: 600px;
    margin: 0 auto var(--space-2xl);
}

.section-tag {
    display: inline-block;
    padding: var(--space-xs) var(--space-md);
    background: var(--bg-secondary);
    color: var(--primary);
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: var(--space-md);
}

.section-header h2 {
    margin-bottom: var(--space-md);
}

/* ==========================================
   Interactive Unit Circle
   ========================================== */
.interactive-section {
    background: linear-gradient(180deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

.interactive-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-2xl);
    align-items: start;
}

@media (max-width: 900px) {
    .interactive-wrapper {
        grid-template-columns: 1fr;
    }
}

.unit-circle-container {
    background: var(--bg-card);
    border-radius: var(--radius-2xl);
    padding: var(--space-xl);
    box-shadow: var(--shadow-lg);
    display: flex;
    flex-direction: column;
    align-items: center;
}

#unit-circle {
    max-width: 100%;
    height: auto;
    cursor: crosshair;
}

.angle-input-wrapper {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin-top: var(--space-lg);
    flex-wrap: wrap;
    justify-content: center;
}

.angle-input-wrapper label {
    font-weight: 600;
    color: var(--text-primary);
}

#angle-slider {
    width: 150px;
    accent-color: var(--primary);
}

#angle-input {
    width: 70px;
    padding: var(--space-sm) var(--space-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: var(--font-mono);
    text-align: center;
}

#angle-input:focus {
    outline: none;
    border-color: var(--primary);
}

.trig-values {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.value-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--space-lg);
    box-shadow: var(--shadow-md);
    border-left: 4px solid;
    transition: transform var(--transition-normal);
}

.value-card:hover {
    transform: translateX(4px);
}

.sin-card { border-color: var(--sin-color); }
.cos-card { border-color: var(--cos-color); }
.tan-card { border-color: var(--tan-color); }

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

.func-name {
    font-family: var(--font-mono);
    font-weight: 600;
    font-size: 1.125rem;
}

.sin-card .func-name { color: var(--sin-color); }
.cos-card .func-name { color: var(--cos-color); }
.tan-card .func-name { color: var(--tan-color); }

.value-badge {
    font-size: 0.75rem;
    padding: var(--space-xs) var(--space-sm);
    background: var(--bg-secondary);
    border-radius: var(--radius-full);
    color: var(--text-muted);
}

.value-display {
    font-family: var(--font-mono);
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-sm);
}

.value-formula {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.coordinates-display {
    background: var(--bg-secondary);
    padding: var(--space-md) var(--space-lg);
    border-radius: var(--radius-lg);
    display: flex;
    justify-content: space-between;
    font-family: var(--font-mono);
    font-size: 0.875rem;
}

/* ==========================================
   Lessons Section
   ========================================== */
.lessons-section {
    background: var(--bg-card);
}

.level-tabs {
    display: flex;
    justify-content: center;
    gap: var(--space-sm);
    margin-bottom: var(--space-xl);
    flex-wrap: wrap;
}

.level-tab {
    padding: var(--space-sm) var(--space-xl);
    background: var(--bg-secondary);
    border: none;
    border-radius: var(--radius-full);
    font-size: 1rem;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-normal);
}

.level-tab:hover {
    background: var(--primary-light);
    color: white;
}

.level-tab.active {
    background: var(--primary);
    color: white;
}

.lessons-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-lg);
}

.lessons-grid.hidden {
    display: none;
}

.lesson-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
    transition: all var(--transition-normal);
    cursor: pointer;
}

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

.lesson-number {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--bg-secondary);
    line-height: 1;
}

.lesson-card:hover .lesson-number {
    color: var(--primary-light);
}

.lesson-content h3 {
    margin-bottom: var(--space-sm);
}

.lesson-content p {
    font-size: 0.875rem;
}

.lesson-meta {
    display: flex;
    gap: var(--space-md);
    margin-top: var(--space-sm);
}

.duration, .difficulty {
    font-size: 0.75rem;
    padding: var(--space-xs) var(--space-sm);
    border-radius: var(--radius-full);
    font-weight: 600;
}

.duration {
    background: var(--bg-secondary);
    color: var(--text-muted);
}

.difficulty.beginner { background: rgba(16, 185, 129, 0.1); color: var(--beginner); }
.difficulty.intermediate { background: rgba(245, 158, 11, 0.1); color: var(--intermediate); }
.difficulty.advanced { background: rgba(239, 68, 68, 0.1); color: var(--advanced); }

.lesson-btn {
    margin-top: auto;
    padding: var(--space-md);
    background: var(--bg-secondary);
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    color: var(--primary);
    cursor: pointer;
    transition: all var(--transition-normal);
}

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

/* ==========================================
   Modal
   ========================================== */
.modal {
    display: none;
    position: fixed;
    inset: 0;
    z-index: 2000;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    padding: var(--space-lg);
    overflow-y: auto;
}

.modal.active {
    display: flex;
    align-items: flex-start;
    justify-content: center;
    padding-top: 80px;
}

.modal-content {
    background: var(--bg-card);
    border-radius: var(--radius-2xl);
    max-width: 800px;
    width: 100%;
    max-height: 85vh;
    overflow-y: auto;
    position: relative;
    animation: modalSlideIn 0.3s ease;
}

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

.modal-close {
    position: absolute;
    top: var(--space-lg);
    right: var(--space-lg);
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    background: var(--bg-secondary);
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
    z-index: 10;
}

.modal-close:hover {
    background: var(--primary);
    color: white;
}

#lesson-body {
    padding: var(--space-2xl);
}

#lesson-body h2 {
    margin-bottom: var(--space-lg);
    padding-right: 60px;
}

#lesson-body h3 {
    margin-top: var(--space-xl);
    margin-bottom: var(--space-md);
    color: var(--primary);
}

#lesson-body p {
    margin-bottom: var(--space-md);
}

#lesson-body ul, #lesson-body ol {
    margin-left: var(--space-xl);
    margin-bottom: var(--space-md);
}

#lesson-body li {
    margin-bottom: var(--space-sm);
}

.lesson-example {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    margin: var(--space-lg) 0;
    border-left: 4px solid var(--primary);
}

.lesson-example h4 {
    color: var(--primary);
    margin-bottom: var(--space-sm);
}

.lesson-interactive {
    background: var(--bg-card);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    margin: var(--space-lg) 0;
    text-align: center;
}

.lesson-interactive canvas {
    max-width: 100%;
}

/* ==========================================
   Graph Section
   ========================================== */
.graph-section {
    background: linear-gradient(180deg, var(--bg-secondary) 0%, var(--bg-primary) 100%);
}

.graph-wrapper {
    display: grid;
    grid-template-columns: 300px 1fr;
    gap: var(--space-xl);
    background: var(--bg-card);
    border-radius: var(--radius-2xl);
    padding: var(--space-xl);
    box-shadow: var(--shadow-lg);
}

@media (max-width: 900px) {
    .graph-wrapper {
        grid-template-columns: 1fr;
    }
}

.graph-controls {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.control-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.control-group label {
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.control-group label span {
    color: var(--primary);
    font-family: var(--font-mono);
}

.control-group select,
.control-group input[type="range"] {
    width: 100%;
}

.control-group select {
    padding: var(--space-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    background: var(--bg-card);
    cursor: pointer;
}

.control-group select:focus {
    outline: none;
    border-color: var(--primary);
}

.control-group input[type="range"] {
    accent-color: var(--primary);
    height: 8px;
}

.formula-display {
    background: var(--bg-secondary);
    padding: var(--space-md);
    border-radius: var(--radius-md);
    font-family: var(--font-mono);
    text-align: center;
    font-size: 1.125rem;
    color: var(--primary);
}

.graph-canvas-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    background: #1e1e2e;
    border-radius: var(--radius-lg);
    overflow: hidden;
}

#graph-canvas {
    max-width: 100%;
    height: auto;
}

/* ==========================================
   Homework/Quiz Section
   ========================================== */
.homework-section {
    background: var(--bg-card);
}

.quiz-container {
    max-width: 700px;
    margin: 0 auto var(--space-2xl);
    background: var(--bg-secondary);
    border-radius: var(--radius-2xl);
    padding: var(--space-xl);
}

.quiz-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-xl);
    flex-wrap: wrap;
    gap: var(--space-md);
}

.quiz-progress {
    flex: 1;
    min-width: 200px;
}

.progress-bar {
    width: 100%;
    height: 8px;
    background: var(--border-color);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: var(--space-sm);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, var(--secondary) 100%);
    width: 10%;
    transition: width var(--transition-normal);
}

#quiz-counter {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.quiz-score {
    font-weight: 700;
    color: var(--primary);
}

.question-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    text-align: center;
}

.question-difficulty {
    display: inline-block;
    padding: var(--space-xs) var(--space-md);
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 600;
    margin-bottom: var(--space-md);
    background: rgba(16, 185, 129, 0.1);
    color: var(--beginner);
}

.question-card h3 {
    font-size: 1.25rem;
    margin-bottom: var(--space-xl);
}

.answer-options {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
}

@media (max-width: 500px) {
    .answer-options {
        grid-template-columns: 1fr;
    }
}

.answer-btn {
    padding: var(--space-md) var(--space-lg);
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.answer-btn:hover {
    border-color: var(--primary);
    background: var(--primary-light);
    color: white;
}

.answer-btn.correct {
    background: var(--beginner);
    border-color: var(--beginner);
    color: white;
}

.answer-btn.incorrect {
    background: var(--advanced);
    border-color: var(--advanced);
    color: white;
}

.answer-btn.disabled {
    pointer-events: none;
}

.feedback-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--space-xl);
    text-align: center;
}

.feedback-card.hidden {
    display: none;
}

.feedback-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-full);
    margin: 0 auto var(--space-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
}

.feedback-card.correct .feedback-icon {
    background: rgba(16, 185, 129, 0.1);
    color: var(--beginner);
}

.feedback-card.incorrect .feedback-icon {
    background: rgba(239, 68, 68, 0.1);
    color: var(--advanced);
}

.feedback-title {
    margin-bottom: var(--space-sm);
}

.feedback-explanation {
    margin-bottom: var(--space-lg);
    font-size: 0.875rem;
}

.quiz-results {
    text-align: center;
    padding: var(--space-2xl);
}

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

.results-icon {
    color: var(--primary);
    margin-bottom: var(--space-lg);
}

.results-score {
    font-size: 1.25rem;
    margin-bottom: var(--space-md);
}

.results-message {
    color: var(--text-muted);
    margin-bottom: var(--space-xl);
}

/* Homework Problems */
.homework-problems h3 {
    text-align: center;
    margin-bottom: var(--space-xl);
}

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

.problem-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    padding: var(--space-lg);
}

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

.problem-number {
    font-weight: 700;
    color: var(--primary);
}

.problem-card > p {
    margin-bottom: var(--space-lg);
    font-size: 0.9375rem;
}

.problem-input {
    display: flex;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
}

.problem-input input {
    flex: 1;
    padding: var(--space-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    background: var(--bg-card);
}

.problem-input input:focus {
    outline: none;
    border-color: var(--primary);
}

.check-btn {
    padding: var(--space-md) var(--space-lg);
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.check-btn:hover {
    background: var(--primary-dark);
}

.problem-hint,
.problem-solution {
    padding: var(--space-md);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    margin-top: var(--space-sm);
}

.problem-hint {
    background: rgba(249, 115, 22, 0.1);
    color: var(--accent);
}

.problem-solution {
    background: rgba(16, 185, 129, 0.1);
    color: var(--beginner);
}

.problem-hint.hidden,
.problem-solution.hidden {
    display: none;
}

/* ==========================================
   Reference Section
   ========================================== */
.reference-section {
    background: linear-gradient(180deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
}

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

.identity-card {
    background: var(--bg-card);
    border-radius: var(--radius-xl);
    padding: var(--space-lg);
    box-shadow: var(--shadow-md);
}

.identity-card h4 {
    color: var(--primary);
    margin-bottom: var(--space-md);
    padding-bottom: var(--space-sm);
    border-bottom: 2px solid var(--border-color);
}

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

.identity {
    padding: var(--space-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-md);
    font-size: 0.9375rem;
    text-align: center;
}

.special-angles-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.875rem;
}

.special-angles-table th,
.special-angles-table td {
    padding: var(--space-sm);
    text-align: center;
    border: 1px solid var(--border-color);
}

.special-angles-table th {
    background: var(--bg-secondary);
    font-weight: 600;
}

.special-angles-table td:first-child {
    font-weight: 600;
    background: var(--bg-secondary);
}

/* ==========================================
   Resources Section
   ========================================== */
.resources-section {
    background: var(--bg-card);
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--space-xl);
}

.resource-category h3 {
    color: var(--primary);
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-sm);
    border-bottom: 2px solid var(--primary-light);
}

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

.resource-item {
    display: flex;
    gap: var(--space-md);
    padding: var(--space-md);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    transition: all var(--transition-normal);
    align-items: flex-start;
    color: var(--text-primary);
}

.resource-item:hover {
    background: var(--primary);
    color: white;
    transform: translateX(4px);
}

.resource-item:hover .resource-info p,
.resource-item:hover .resource-icon {
    color: rgba(255, 255, 255, 0.8);
}

.resource-icon {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    background: var(--bg-card);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary);
}

.resource-item:hover .resource-icon {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.resource-info {
    flex: 1;
}

.resource-info h4 {
    font-size: 0.9375rem;
    margin-bottom: var(--space-xs);
}

.resource-info p {
    font-size: 0.8125rem;
    color: var(--text-muted);
    line-height: 1.4;
}

.resource-badge {
    flex-shrink: 0;
    padding: var(--space-xs) var(--space-sm);
    background: var(--bg-card);
    border-radius: var(--radius-full);
    font-size: 0.6875rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
}

.resource-badge.free {
    background: rgba(16, 185, 129, 0.1);
    color: var(--beginner);
}

.resource-item:hover .resource-badge {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

/* ==========================================
   Footer
   ========================================== */
.footer {
    background: var(--text-primary);
    color: var(--bg-primary);
    padding: var(--space-2xl) 0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    gap: var(--space-2xl);
    flex-wrap: wrap;
    margin-bottom: var(--space-xl);
}

.footer-brand {
    max-width: 300px;
}

.footer-brand .logo {
    color: white;
    margin-bottom: var(--space-md);
}

.footer-brand .logo svg {
    color: white;
}

.footer-brand p {
    color: var(--text-muted);
    font-size: 0.875rem;
}

.footer-links {
    display: flex;
    gap: var(--space-2xl);
}

.footer-column h4 {
    color: white;
    margin-bottom: var(--space-md);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.footer-column a {
    display: block;
    color: var(--text-muted);
    font-size: 0.875rem;
    margin-bottom: var(--space-sm);
    transition: color var(--transition-fast);
}

.footer-column a:hover {
    color: white;
}

.footer-bottom {
    padding-top: var(--space-xl);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    text-align: center;
}

.footer-bottom p {
    color: var(--text-muted);
    font-size: 0.875rem;
}

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

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

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.animate-fade-in {
    animation: fadeIn 0.6s ease forwards;
}

.animate-slide-up {
    animation: slideUp 0.6s ease forwards;
}

/* ==========================================
   Responsive Adjustments
   ========================================== */
@media (max-width: 640px) {
    .hero-stats {
        flex-direction: column;
        gap: var(--space-lg);
    }

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

    .footer-content {
        flex-direction: column;
    }

    .footer-links {
        flex-direction: column;
        gap: var(--space-lg);
    }
}

/* Print styles */
@media print {
    .navbar, .hero-bg, .btn, .quiz-container {
        display: none !important;
    }

    body {
        background: white;
        color: black;
    }

    .section {
        page-break-inside: avoid;
    }
}