:root {
    --bg-color: #050609;
    --surface-color: #0f1117;
    --surface-lighter: #1a1d26;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #6366f1; /* Modern Indigo */
    --accent-glow: rgba(99, 102, 241, 0.4);
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --nav-bg: rgba(5, 6, 9, 0.85);
    --transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    --card-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.7);
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    overflow-x: hidden;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

/* --- SCROLLBAR --- */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-color);
}

::-webkit-scrollbar-thumb {
    background: #27272a;
    border-radius: 20px;
    border: 2px solid var(--bg-color);
}

::-webkit-scrollbar-thumb:hover {
    background: #3f3f46;
}

/* --- NAVIGATION --- */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    height: 72px;
    background-color: var(--nav-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 6%;
    z-index: 1000;
    border-bottom: 1px solid var(--glass-border);
}

.logo {
    font-size: 22px;
    font-weight: 900;
    color: white;
    text-decoration: none;
    letter-spacing: -0.5px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo::before {
    content: '';
    width: 12px;
    height: 12px;
    background: var(--accent-color);
    border-radius: 3px;
    box-shadow: 0 0 15px var(--accent-glow);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-item {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: var(--transition);
}

.nav-item:hover, .nav-item.active {
    color: white;
}

.search-bar {
    display: flex;
    align-items: center;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 0 16px;
    width: 320px;
    margin: 0 40px;
    transition: var(--transition);
}

.search-bar:focus-within {
    border-color: var(--accent-color);
    background: rgba(255, 255, 255, 0.05);
    box-shadow: 0 0 20px rgba(99, 102, 241, 0.15);
}

.search-bar input {
    background: transparent;
    border: none;
    color: white;
    padding: 10px 0;
    width: 100%;
    outline: none;
    font-size: 14px;
}

.user-actions {
    display: flex;
    align-items: center;
    gap: 20px;
}

/* --- GAMIFICATION STATS --- */
.gamification-stats {
    display: flex;
    align-items: center;
    gap: 8px;
}

.stat-item {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: var(--surface-lighter);
    border: 1px solid var(--glass-border);
    border-radius: 10px;
    font-weight: 700;
    font-size: 13px;
    white-space: nowrap;
}

.stat-item.streak {
    color: #ff9600;
    background: rgba(255, 150, 0, 0.05);
}

.stat-item.xp {
    color: #00d4ff;
    background: rgba(0, 212, 255, 0.05);
}

.user-avatar-nav {
    width: 38px;
    height: 38px;
    border-radius: 12px;
    background-size: cover;
    background-position: center;
    border: 2px solid var(--glass-border);
    transition: var(--transition);
}

.user-avatar-nav:hover {
    border-color: var(--accent-color);
    transform: scale(1.05);
}

.btn-logout-header {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 13px;
    font-weight: 700;
    padding: 8px 12px;
    border-radius: 8px;
    transition: var(--transition);
}

.btn-logout-header:hover {
    color: var(--danger-color);
    background: rgba(239, 68, 68, 0.1);
}

/* --- HERO SECTION --- */
.hero {
    min-height: 90vh;
    display: flex;
    align-items: center;
    padding: 120px 6% 60px;
    background: radial-gradient(circle at 80% 20%, rgba(99, 102, 241, 0.15) 0%, transparent 40%),
                radial-gradient(circle at 10% 80%, rgba(229, 9, 20, 0.1) 0%, transparent 40%);
    position: relative;
    overflow: hidden;
}

.hero::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 300px;
    background: linear-gradient(to top, var(--bg-color), transparent);
}

.hero-content {
    max-width: 700px;
    z-index: 10;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 12px;
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid rgba(99, 102, 241, 0.2);
    border-radius: 100px;
    color: var(--accent-color);
    font-size: 12px;
    font-weight: 700;
    margin-bottom: 24px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.hero h1 {
    font-size: clamp(40px, 6vw, 72px);
    font-weight: 900;
    line-height: 1;
    margin-bottom: 24px;
    letter-spacing: -2px;
    background: linear-gradient(to bottom, #fff, #94a3b8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: clamp(16px, 2vw, 20px);
    color: var(--text-secondary);
    margin-bottom: 40px;
    max-width: 540px;
}

.hero-buttons {
    display: flex;
    gap: 16px;
}

/* --- BUTTONS --- */
.btn-play {
    background: white;
    color: black;
    padding: 14px 32px;
    border-radius: 12px;
    font-weight: 700;
    font-size: 16px;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
}

.btn-play:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(255, 255, 255, 0.2);
}

.btn-more {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: white;
    padding: 14px 32px;
    border-radius: 12px;
    font-weight: 700;
    font-size: 16px;
    border: 1px solid var(--glass-border);
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

.btn-more:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.2);
}

.btn-primary {
    background: var(--accent-color);
    color: white;
    padding: 10px 24px;
    border-radius: 12px;
    font-weight: 700;
    text-decoration: none;
    transition: var(--transition);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px var(--accent-glow);
}

.btn-secondary {
    background: var(--glass-bg);
    color: white;
    padding: 10px 24px;
    border-radius: 12px;
    font-weight: 700;
    text-decoration: none;
    border: 1px solid var(--glass-border);
    transition: var(--transition);
}

.btn-text {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: var(--transition);
}

.btn-text:hover {
    color: white;
}

/* --- CONTENT ROWS --- */
.content-row {
    padding: 60px 6% 0;
}

.row-title {
    font-size: 24px;
    font-weight: 800;
    margin-bottom: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.course-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
}

.course-card {
    background: var(--surface-color);
    border-radius: 24px;
    overflow: hidden;
    border: 1px solid var(--glass-border);
    transition: var(--transition);
    cursor: pointer;
    position: relative;
}

.course-card:hover {
    transform: translateY(-8px);
    border-color: rgba(99, 102, 241, 0.3);
    box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.5);
}

.card-image {
    height: 180px;
    background-size: cover;
    background-position: center;
    position: relative;
}

.card-image::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, var(--surface-color), transparent);
}

.card-info {
    padding: 24px;
}

.card-info h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
    color: white;
}

.instructor {
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.card-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 12px;
    font-weight: 600;
}

.rating {
    color: var(--warning-color);
    display: flex;
    align-items: center;
    gap: 4px;
}

.student-count {
    color: var(--text-secondary);
}

.badge {
    position: absolute;
    top: 16px;
    right: 16px;
    padding: 6px 12px;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    font-size: 10px;
    font-weight: 800;
    letter-spacing: 0.5px;
    color: white;
    z-index: 5;
}

/* --- CATEGORIES --- */
.categories-section {
    padding: 80px 6% 0;
}

.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 16px;
}

.category-card {
    background: var(--surface-color);
    padding: 24px;
    border-radius: 20px;
    text-align: center;
    border: 1px solid var(--glass-border);
    font-weight: 700;
    font-size: 14px;
    transition: var(--transition);
    cursor: pointer;
}

.category-card:hover {
    background: var(--accent-color);
    border-color: var(--accent-color);
    box-shadow: 0 10px 25px var(--accent-glow);
    transform: translateY(-4px);
}

/* --- INSTRUCTORS --- */
.instructors-section {
    padding: 80px 6% 0;
}

.instructor-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 24px;
}

.instructor-card {
    background: var(--surface-color);
    padding: 32px;
    border-radius: 24px;
    text-align: center;
    border: 1px solid var(--glass-border);
    transition: var(--transition);
}

.instructor-card:hover {
    border-color: var(--glass-border);
    background: var(--surface-lighter);
}

.inst-avatar {
    width: 100px;
    height: 100px;
    border-radius: 32px;
    margin: 0 auto 20px;
    background-size: cover;
    background-position: center;
    border: 3px solid var(--bg-color);
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
}

/* --- FOOTER --- */
.main-footer {
    margin-top: 120px;
    background: var(--surface-color);
    padding: 80px 6% 40px;
    border-top: 1px solid var(--glass-border);
}

.footer-top {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 80px;
    margin-bottom: 60px;
}

.footer-brand p {
    color: var(--text-secondary);
    margin-top: 20px;
    max-width: 400px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.link-group h4 {
    font-size: 14px;
    font-weight: 700;
    margin-bottom: 20px;
    color: white;
}

.link-group a {
    display: block;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
    margin-bottom: 12px;
    transition: var(--transition);
}

.link-group a:hover {
    color: white;
}

.footer-bottom {
    padding-top: 40px;
    border-top: 1px solid var(--glass-border);
    text-align: center;
    font-size: 13px;
    color: var(--text-secondary);
}

/* --- AUTH PAGES --- */
.auth-page {
    background-color: var(--bg-color);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
}

.auth-box {
    background: var(--surface-color);
    padding: 60px;
    border-radius: 32px;
    width: 100%;
    max-width: 480px;
    border: 1px solid var(--glass-border);
    box-shadow: 0 40px 80px rgba(0, 0, 0, 0.6);
}

.auth-box h1 {
    font-size: 32px;
    font-weight: 900;
    margin-bottom: 12px;
    text-align: center;
}

.auth-form .form-group {
    margin-bottom: 24px;
}

.auth-form label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.auth-form input {
    width: 100%;
    background: var(--bg-color);
    border: 1px solid var(--glass-border);
    padding: 14px 20px;
    border-radius: 14px;
    color: white;
    font-size: 15px;
    transition: var(--transition);
}

.auth-form input:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1);
    outline: none;
}

.btn-auth {
    width: 100%;
    background: var(--accent-color);
    color: white;
    padding: 16px;
    border-radius: 14px;
    font-weight: 700;
    font-size: 16px;
    border: none;
    cursor: pointer;
    margin-top: 12px;
    transition: var(--transition);
}

.btn-auth:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px var(--accent-glow);
}

/* --- PLAYER PAGE --- */
.player-container {
    display: grid;
    grid-template-columns: 1fr 400px;
    margin-top: 72px;
    height: calc(100vh - 72px);
}

.video-section {
    background: black;
    display: flex;
    flex-direction: column;
}

.video-player {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    background: #000;
}

.video-info {
    background: var(--bg-color);
    padding: 32px 6%;
}

.curriculum-section {
    background: var(--surface-color);
    border-left: 1px solid var(--glass-border);
    overflow-y: auto;
}

.curriculum-header {
    padding: 24px;
    border-bottom: 1px solid var(--glass-border);
}

.section-item {
    border-bottom: 1px solid var(--glass-border);
}

.section-title {
    background: var(--surface-lighter);
    padding: 16px 24px;
    font-size: 14px;
    font-weight: 700;
}

.lesson-item {
    padding: 16px 24px;
    display: flex;
    align-items: center;
    gap: 16px;
    cursor: pointer;
    transition: var(--transition);
}

.lesson-item:hover {
    background: var(--surface-lighter);
}

/* --- PROFILE PREMIUM DASHBOARD --- */
.profile-container-new {
    padding-top: 100px;
    max-width: 1400px;
    margin: 0 auto;
    padding-bottom: 100px;
}

.profile-header-premium {
    background: var(--surface-color);
    border-radius: 32px;
    margin: 0 4% 48px;
    border: 1px solid var(--glass-border);
    overflow: hidden;
    position: relative;
    box-shadow: var(--card-shadow);
}

.profile-cover-image {
    height: 180px;
    background: linear-gradient(135deg, var(--accent-color) 0%, #a855f7 100%);
    opacity: 0.15;
    position: relative;
}

.profile-header-content {
    padding: 0 48px 40px;
    display: flex;
    align-items: flex-end;
    gap: 40px;
    margin-top: -60px;
}

.profile-avatar-large {
    width: 160px;
    height: 160px;
    border-radius: 40px;
    background-size: cover;
    background-position: center;
    border: 6px solid var(--surface-color);
    box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    position: relative;
    z-index: 5;
}

.profile-user-info {
    flex: 1;
    padding-bottom: 10px;
}

.profile-name-badge {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-bottom: 8px;
}

.profile-name-badge h1 {
    font-size: clamp(24px, 4vw, 36px);
    font-weight: 900;
    letter-spacing: -1px;
}

.elite-status-badge {
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid rgba(99, 102, 241, 0.2);
    color: var(--accent-color);
    padding: 6px 14px;
    border-radius: 100px;
    font-size: 11px;
    font-weight: 800;
    letter-spacing: 1px;
}

.profile-bio-text {
    color: var(--text-secondary);
    font-size: 15px;
    max-width: 600px;
    margin-bottom: 32px;
    line-height: 1.6;
}

.profile-stats-grid {
    display: flex;
    gap: 48px;
}

.p-stat-item {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.p-stat-value {
    font-size: 24px;
    font-weight: 900;
    color: white;
}

.p-stat-label {
    font-size: 10px;
    font-weight: 800;
    color: var(--text-secondary);
    letter-spacing: 1px;
}

.profile-header-actions {
    display: flex;
    gap: 12px;
    padding-bottom: 15px;
}

.btn-edit-modern, .btn-share-modern {
    padding: 12px 24px;
    border-radius: 14px;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

.btn-edit-modern {
    background: white;
    color: black;
}

.btn-edit-modern:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(255,255,255,0.1);
}

.btn-share-modern {
    background: var(--surface-lighter);
    color: white;
    border: 1px solid var(--glass-border);
}

.btn-share-modern:hover {
    background: var(--glass-border);
}

.profile-grid-layout {
    display: grid;
    grid-template-columns: 1fr 340px;
    gap: 40px;
    padding: 0 4%;
}

.dashboard-section {
    margin-bottom: 56px;
}

.section-header {
    margin-bottom: 24px;
}

.section-header h2 {
    font-size: 22px;
    font-weight: 800;
    margin-bottom: 4px;
}

.section-header p {
    font-size: 14px;
    color: var(--text-secondary);
}

.active-courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
}

.empty-dashboard-state {
    grid-column: 1 / -1;
    background: var(--surface-color);
    border: 2px dashed var(--glass-border);
    border-radius: 32px;
    padding: 60px 40px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    transition: var(--transition);
}

.empty-dashboard-state:hover {
    border-color: var(--accent-color);
    background: rgba(99, 102, 241, 0.02);
}

.empty-icon-v2 {
    font-size: 48px;
    margin-bottom: 8px;
    filter: drop-shadow(0 0 15px rgba(255,255,255,0.1));
}

.empty-dashboard-state h3 {
    font-size: 20px;
    font-weight: 800;
    color: white;
}

.empty-dashboard-state p {
    font-size: 14px;
    color: var(--text-secondary);
    max-width: 300px;
    margin-bottom: 8px;
}

.premium-course-card {
    background: var(--surface-color);
    border-radius: 24px;
    border: 1px solid var(--glass-border);
    padding: 12px;
    display: flex;
    gap: 20px;
    transition: var(--transition);
    cursor: pointer;
}

.premium-course-card:hover {
    border-color: var(--accent-color);
    transform: translateX(8px);
    background: var(--surface-lighter);
}

.p-course-img {
    width: 100px;
    height: 100px;
    border-radius: 16px;
    background-size: cover;
    background-position: center;
    flex-shrink: 0;
}

.p-course-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.p-course-info h3 {
    font-size: 15px;
    font-weight: 700;
    margin-bottom: 12px;
}

.p-progress-wrapper {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.p-progress-bar {
    flex: 1;
    height: 6px;
    background: var(--bg-color);
    border-radius: 10px;
    overflow: hidden;
}

.p-progress-fill {
    height: 100%;
    background: var(--accent-color);
    box-shadow: 0 0 10px var(--accent-glow);
}

.p-progress-percent {
    font-size: 12px;
    font-weight: 800;
    color: var(--accent-color);
}

.btn-resume-small {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    font-size: 11px;
    font-weight: 700;
    text-align: left;
    padding: 0;
    cursor: pointer;
}

.badges-mini-row {
    display: flex;
    flex-wrap: wrap;
    gap: 16px;
    background: var(--surface-color);
    padding: 32px;
    border-radius: 24px;
    border: 1px solid var(--glass-border);
}

.achievement-badge-v2 {
    width: 64px;
    height: 64px;
    background: var(--bg-color);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    border: 1px solid var(--glass-border);
    transition: var(--transition);
}

.achievement-badge-v2:hover {
    transform: scale(1.1) rotate(5deg);
    border-color: var(--accent-color);
    box-shadow: 0 10px 20px var(--accent-glow);
}

.side-card-modern {
    background: var(--surface-color);
    padding: 32px;
    border-radius: 24px;
    border: 1px solid var(--glass-border);
    margin-bottom: 24px;
}

.side-card-modern h3 {
    font-size: 16px;
    font-weight: 800;
    margin-bottom: 24px;
}

.modern-skills-list {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.modern-skill-tag {
    background: var(--surface-lighter);
    padding: 8px 16px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 700;
    color: var(--text-secondary);
    border: 1px solid var(--glass-border);
}

.modern-activity-chart {
    display: flex;
    align-items: flex-end;
    justify-content: space-between;
    height: 120px;
    gap: 8px;
}

.m-chart-bar-group {
    flex: 1;
    height: 100%;
    display: flex;
    align-items: flex-end;
}

.m-chart-bar {
    width: 100%;
    background: var(--accent-color);
    border-radius: 6px 6px 2px 2px;
    opacity: 0.4;
    transition: var(--transition);
}

.m-chart-bar:hover {
    opacity: 1;
    box-shadow: 0 0 15px var(--accent-glow);
}

.m-chart-labels {
    display: flex;
    justify-content: space-between;
    margin-top: 16px;
    font-size: 11px;
    font-weight: 800;
    color: var(--text-secondary);
}

.m-chart-hint {
    margin-top: 20px;
    font-size: 12px;
    color: #4b5563;
    text-align: center;
}

@media (max-width: 1100px) {
    .profile-grid-layout { grid-template-columns: 1fr; }
    .profile-header-content { flex-direction: column; align-items: center; text-align: center; }
    .profile-stats-grid { justify-content: center; }
}

.instructor-card-link:hover {
    border-color: var(--accent-color) !important;
    transform: translateY(-2px);
    background: var(--surface-lighter) !important;
    box-shadow: 0 10px 20px rgba(0,0,0,0.2);
}

.profile-page-main, .instructor-page-main, .achievements-page-main {
    min-height: 100vh;
}

.achievement-icon-v3 {
    transition: var(--transition);
}

.premium-course-card.unlocked:hover .achievement-icon-v3 {
    transform: scale(1.1) rotate(8deg);
}

.locked-opacity {
    transition: var(--transition);
}

/* --- RESPONSIVE --- */
@media (max-width: 1024px) {
    .player-container { grid-template-columns: 1fr; height: auto; }
    .footer-top { grid-template-columns: 1fr; gap: 40px; }
    .footer-links { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .navbar { padding: 0 4%; }
    .search-bar { display: none; }
    .hero { text-align: center; justify-content: center; }
    .hero h1 { font-size: 48px; }
    .hero-buttons { justify-content: center; }
    .footer-links { grid-template-columns: 1fr; }
}