/* ========================================
   CodeQuest - CSS Styles
   Color Palette focused on Learning
   ======================================== */

:root {
    /* Primary Colors - Focused on Learning */
    --primary-blue: #3B82F6;
    --primary-purple: #8B5CF6;
    --primary-green: #10B981;
    --primary-orange: #F59E0B;
    
    /* Track Colors */
    --html-color: #E34F26;
    --css-color: #1572B6;
    --js-color: #F7DF1E;
    --java-color: #007396;
    
    /* Neutral Colors */
    --bg-primary: #0F172A;
    --bg-secondary: #1E293B;
    --bg-tertiary: #334155;
    --text-primary: #F1F5F9;
    --text-secondary: #CBD5E1;
    --text-muted: #94A3B8;
    
    /* Status Colors */
    --success: #10B981;
    --warning: #F59E0B;
    --error: #EF4444;
    --info: #3B82F6;
    
    /* Shadows */
    --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, 0.2);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.3);
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;
}

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

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

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

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

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

.header {
    background: var(--bg-secondary);
    border-bottom: 2px solid var(--bg-tertiary);
    padding: var(--spacing-md) 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-lg);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-xl);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.logo i {
    font-size: 2rem;
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav {
    display: flex;
    gap: var(--spacing-sm);
}

.nav-link {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--text-secondary);
    text-decoration: none;
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
    font-size: 0.875rem;
    font-weight: 500;
}

.nav-link i {
    font-size: 1.25rem;
}

.nav-link:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    transform: translateY(-2px);
}

.nav-link.active {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    color: white;
}

.user-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.streak-counter,
.xp-counter {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    font-weight: 600;
}

.streak-counter i {
    color: var(--primary-orange);
    font-size: 1.25rem;
}

.xp-counter i {
    color: var(--primary-green);
    font-size: 1.25rem;
}

.user-avatar {
    width: 45px;
    height: 45px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, var(--primary-purple), var(--primary-blue));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    cursor: pointer;
    transition: transform var(--transition-base);
}

.user-avatar:hover {
    transform: scale(1.1);
}

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

.main-content {
    padding: var(--spacing-2xl) 0;
    min-height: calc(100vh - 80px);
}

.page {
    display: none;
    animation: fadeIn 0.3s ease;
}

.page.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.page-title {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: var(--spacing-xl);
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ========================================
   Home Page
   ======================================== */

.welcome-banner {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    padding: var(--spacing-xl);
    border-radius: var(--radius-xl);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-xl);
}

.welcome-banner h2 {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.welcome-banner p {
    font-size: 1.125rem;
    opacity: 0.9;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
}

.stat-card {
    background: var(--bg-secondary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    transition: all var(--transition-base);
    border: 2px solid transparent;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-blue);
}

.stat-icon {
    width: 60px;
    height: 60px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
}

.stat-info h3 {
    font-size: 2rem;
    font-weight: 800;
    color: var(--text-primary);
}

.stat-info p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.quick-access {
    background: var(--bg-secondary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
}

.quick-access h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
}

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

.track-card {
    background: var(--bg-tertiary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-base);
    border: 2px solid transparent;
}

.track-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.track-card[data-track="html"]:hover {
    border-color: var(--html-color);
}

.track-card[data-track="css"]:hover {
    border-color: var(--css-color);
}

.track-card[data-track="javascript"]:hover {
    border-color: var(--js-color);
}

.track-card[data-track="java"]:hover {
    border-color: var(--java-color);
}

.track-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--spacing-md);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
}

.track-card[data-track="html"] .track-icon {
    background: linear-gradient(135deg, #E34F26, #FF6B35);
    color: white;
}

.track-card[data-track="css"] .track-icon {
    background: linear-gradient(135deg, #1572B6, #33A9DC);
    color: white;
}

.track-card[data-track="javascript"] .track-icon {
    background: linear-gradient(135deg, #F7DF1E, #FFD700);
    color: #000;
}

.track-card[data-track="java"] .track-icon {
    background: linear-gradient(135deg, #007396, #0097D3);
    color: white;
}

.track-card h4 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

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

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-blue), var(--primary-purple));
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
}

.progress-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* ========================================
   Learn Page
   ======================================== */

.track-selector {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
    flex-wrap: wrap;
}

.track-btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: 2px solid var(--bg-tertiary);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.track-btn i {
    font-size: 1.5rem;
}

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

.track-btn.active {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    border-color: transparent;
}

.lessons-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.lesson-card {
    background: var(--bg-secondary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    border: 2px solid transparent;
    position: relative;
}

.lesson-card:hover {
    transform: translateX(10px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-blue);
}

.lesson-card.completed {
    border-color: var(--success);
}

.lesson-card.locked {
    opacity: 0.5;
    cursor: not-allowed;
}

.lesson-card.locked:hover {
    transform: none;
}

.lesson-number {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.25rem;
}

.lesson-card.completed .lesson-number {
    background: var(--success);
}

.lesson-card.locked .lesson-number {
    background: var(--bg-tertiary);
}

.lesson-info {
    flex: 1;
}

.lesson-info h4 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.lesson-info p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.lesson-meta {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    color: var(--text-secondary);
}

.lesson-xp {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-weight: 600;
}

.lesson-xp i {
    color: var(--primary-green);
}

.premium-badge {
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #000;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* ========================================
   Ranking Page
   ======================================== */

.ranking-filters {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.filter-btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: 2px solid var(--bg-tertiary);
    background: var(--bg-secondary);
    color: var(--text-primary);
    border-radius: var(--radius-lg);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
}

.filter-btn:hover {
    background: var(--bg-tertiary);
}

.filter-btn.active {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    border-color: transparent;
}

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

.ranking-item {
    background: var(--bg-secondary);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    transition: all var(--transition-base);
}

.ranking-item:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-md);
}

.ranking-item.top-1 {
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #000;
}

.ranking-item.top-2 {
    background: linear-gradient(135deg, #C0C0C0, #808080);
}

.ranking-item.top-3 {
    background: linear-gradient(135deg, #CD7F32, #8B4513);
}

.ranking-position {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    background: var(--bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.125rem;
}

.ranking-item.top-1 .ranking-position,
.ranking-item.top-2 .ranking-position,
.ranking-item.top-3 .ranking-position {
    background: rgba(0, 0, 0, 0.2);
}

.ranking-avatar {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    background: var(--bg-tertiary);
}

.ranking-item.top-1 .ranking-avatar,
.ranking-item.top-2 .ranking-avatar,
.ranking-item.top-3 .ranking-avatar {
    background: rgba(0, 0, 0, 0.2);
}

.ranking-user-info {
    flex: 1;
}

.ranking-user-info h4 {
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.ranking-user-info p {
    font-size: 0.875rem;
    opacity: 0.8;
}

.ranking-xp {
    font-size: 1.25rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* ========================================
   Achievements Page
   ======================================== */

.achievements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--spacing-lg);
}

.achievement-card {
    background: var(--bg-secondary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-align: center;
    transition: all var(--transition-base);
    border: 2px solid transparent;
}

.achievement-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-blue);
}

.achievement-card.locked {
    opacity: 0.4;
}

.achievement-icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-md);
    filter: grayscale(0);
}

.achievement-card.locked .achievement-icon {
    filter: grayscale(1);
}

.achievement-card h4 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.achievement-card p {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* ========================================
   Profile Page
   ======================================== */

.profile-header {
    background: var(--bg-secondary);
    padding: var(--spacing-2xl);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.profile-avatar-large {
    width: 100px;
    height: 100px;
    border-radius: var(--radius-full);
    background: linear-gradient(135deg, var(--primary-purple), var(--primary-blue));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3rem;
}

.profile-info {
    flex: 1;
}

.profile-info h2 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: var(--spacing-xs);
}

.profile-info p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-md);
}

.profile-plan {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-lg);
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    font-weight: 600;
}

.btn-upgrade {
    padding: var(--spacing-md) var(--spacing-xl);
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #000;
    border: none;
    border-radius: var(--radius-lg);
    font-weight: 700;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-base);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

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

.profile-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.stat-box {
    background: var(--bg-secondary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-align: center;
}

.stat-box i {
    font-size: 2.5rem;
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: var(--spacing-md);
}

.stat-box h3 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: var(--spacing-xs);
}

.stat-box p {
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.progress-tracks {
    background: var(--bg-secondary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
}

.progress-tracks h3 {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: var(--spacing-lg);
}

.track-progress-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.track-progress-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.track-progress-icon {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: white;
}

.track-progress-info {
    flex: 1;
}

.track-progress-info h4 {
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

/* ========================================
   Modal
   ======================================== */

.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    z-index: 1000;
    align-items: center;
    justify-content: center;
    animation: fadeIn 0.3s ease;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    max-width: 600px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: var(--shadow-xl);
    animation: slideUp 0.3s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-header {
    padding: var(--spacing-xl);
    border-bottom: 2px solid var(--bg-tertiary);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    font-size: 1.5rem;
    font-weight: 700;
}

.modal-close {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    background: var(--bg-tertiary);
    border: none;
    color: var(--text-primary);
    font-size: 1.25rem;
    cursor: pointer;
    transition: all var(--transition-base);
}

.modal-close:hover {
    background: var(--error);
    transform: rotate(90deg);
}

.modal-body {
    padding: var(--spacing-xl);
}

.question-card {
    background: var(--bg-tertiary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
}

.question-card h4 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
}

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

.option-btn {
    padding: var(--spacing-md);
    background: var(--bg-primary);
    border: 2px solid var(--bg-tertiary);
    color: var(--text-primary);
    border-radius: var(--radius-md);
    text-align: left;
    cursor: pointer;
    transition: all var(--transition-base);
    font-size: 1rem;
}

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

.option-btn.correct {
    border-color: var(--success);
    background: rgba(16, 185, 129, 0.1);
}

.option-btn.incorrect {
    border-color: var(--error);
    background: rgba(239, 68, 68, 0.1);
}

.lesson-result {
    text-align: center;
    padding: var(--spacing-xl);
}

.result-icon {
    font-size: 5rem;
    margin-bottom: var(--spacing-lg);
}

.lesson-result h3 {
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: var(--spacing-md);
}

.lesson-result p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-xl);
}

.result-actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
}

.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-lg);
    font-weight: 700;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-base);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    color: white;
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

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

/* ========================================
   Upgrade Modal
   ======================================== */

.upgrade-content {
    max-width: 800px;
}

.plans-comparison {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-xl);
}

.plan-card {
    background: var(--bg-tertiary);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    position: relative;
}

.plan-card.premium {
    border: 3px solid #FFD700;
}

.plan-badge {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #000;
    padding: var(--spacing-xs) var(--spacing-lg);
    border-radius: var(--radius-full);
    font-weight: 700;
    font-size: 0.875rem;
}

.plan-card h4 {
    font-size: 1.5rem;
    font-weight: 800;
    margin-bottom: var(--spacing-lg);
    text-align: center;
}

.plan-price {
    font-size: 3rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: var(--spacing-lg);
    background: linear-gradient(135deg, var(--primary-blue), var(--primary-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.plan-price span {
    font-size: 1rem;
    font-weight: 600;
}

.plan-features {
    list-style: none;
    margin-bottom: var(--spacing-xl);
}

.plan-features li {
    padding: var(--spacing-sm) 0;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.plan-features li i {
    color: var(--success);
}

.plan-features li.disabled i {
    color: var(--error);
}

.btn-premium {
    width: 100%;
    padding: var(--spacing-md);
    background: linear-gradient(135deg, #FFD700, #FFA500);
    color: #000;
    border: none;
    border-radius: var(--radius-lg);
    font-weight: 700;
    font-size: 1.125rem;
    cursor: pointer;
    transition: all var(--transition-base);
}

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

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

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .nav {
        width: 100%;
        justify-content: space-around;
    }
    
    .nav-link span {
        display: none;
    }
    
    .stats-grid,
    .tracks-preview,
    .achievements-grid {
        grid-template-columns: 1fr;
    }
    
    .track-selector {
        flex-direction: column;
    }
    
    .profile-header {
        flex-direction: column;
        text-align: center;
    }
    
    .plans-comparison {
        grid-template-columns: 1fr;
    }
}