/* ============================================
   Codimous - AI Coding Education Platform
   Complete Stylesheet
   ============================================ */

/* ---------- CSS Variables ---------- */
:root {
  --bg-body: #0a0a0f;
  --bg-card: #12121a;
  --bg-elevated: #1a1a2e;
  --bg-nav: #0f0f1a;
  --border: #2a2a3e;
  --accent: #00d4aa;
  --accent-hover: #00e8bb;
  --accent-glow: #00d4aa22;
  --accent-muted: #00d4aa33;
  --secondary: #7c3aed;
  --secondary-hover: #8b4ff0;
  --danger: #ef4444;
  --warning: #f59e0b;
  --success: #22c55e;
  --text-primary: #e8e8f0;
  --text-secondary: #b0b0c0;
  --text-muted: #888899;
  --radius-card: 12px;
  --radius-btn: 8px;
  --radius-input: 8px;
  --transition: 0.3s ease;
  --font-ui: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-code: 'Fira Code', 'Consolas', 'Monaco', monospace;
  --nav-height: 64px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-body);
  color: var(--text-primary);
  font-family: var(--font-ui);
  font-size: 16px;
  line-height: 1.6;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a:hover {
  color: var(--accent-hover);
}

::selection {
  background: var(--accent-muted);
}

img {
  max-width: 100%;
  display: block;
}

ul, ol {
  list-style: none;
}

/* ---------- Typography ---------- */
h1 {
  font-size: 2.5rem;
  font-weight: 700;
  line-height: 1.2;
  color: var(--text-primary);
}

h2 {
  font-size: 2rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--text-primary);
}

h3 {
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text-primary);
}

h4 {
  font-size: 1.2rem;
  font-weight: 600;
}

.text-muted {
  color: var(--text-muted);
}

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

.text-accent {
  color: var(--accent);
}

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

code,
pre {
  font-family: var(--font-code);
}

code {
  background: var(--bg-elevated);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.9em;
  color: var(--accent);
}

pre {
  background: var(--bg-elevated);
  border-radius: var(--radius-btn);
  padding: 16px;
  overflow-x: auto;
  border: 1px solid var(--border);
}

pre code {
  background: none;
  padding: 0;
  color: var(--text-primary);
}

/* ---------- Navbar ---------- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--bg-nav);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  display: flex;
  align-items: center;
}

.nav-inner {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--text-primary) !important;
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo i {
  color: var(--accent);
  font-size: 1.5rem;
}

.logo:hover {
  color: var(--accent) !important;
}

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

.nav-links {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  color: var(--text-secondary) !important;
  padding: 8px 16px;
  border-radius: var(--radius-btn);
  font-weight: 500;
  font-size: 0.95rem;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent) !important;
  background: var(--accent-glow);
}

.lang-switcher {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-right: 12px;
  padding: 2px;
  background: var(--bg-elevated);
  border-radius: 6px;
  border: 1px solid var(--border);
}

.lang-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  font-family: var(--font-ui);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 4px 8px;
  border-radius: 4px;
  cursor: pointer;
  transition: var(--transition);
  letter-spacing: 0.5px;
}

.lang-btn:hover {
  color: var(--text-primary);
}

.lang-btn.active {
  background: var(--accent);
  color: var(--bg-body);
}

.nav-auth {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-auth > div {
  display: flex;
  align-items: center;
  gap: 12px;
}

.nav-user {
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 500;
}

.nav-user i {
  color: var(--accent);
  font-size: 1.2rem;
}

.hamburger {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.4rem;
  cursor: pointer;
  padding: 8px;
}

/* Auth visibility */
.guest-only { display: flex; }
.auth-only { display: none; }
body.authenticated .guest-only { display: none !important; }
body.authenticated .auth-only { display: flex !important; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 24px;
  border-radius: var(--radius-btn);
  font-family: var(--font-ui);
  font-size: 0.95rem;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
  text-decoration: none;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  background: var(--accent);
  color: var(--bg-body);
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: var(--bg-body);
  box-shadow: 0 4px 20px var(--accent-muted);
}

.btn-secondary {
  background: var(--secondary);
  color: #fff;
}

.btn-secondary:hover {
  background: var(--secondary-hover);
  box-shadow: 0 4px 20px rgba(124, 58, 237, 0.3);
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--accent);
  color: var(--accent);
}

.btn-outline:hover {
  background: var(--accent);
  color: var(--bg-body);
}

.btn-danger {
  background: var(--danger);
  color: #fff;
}

.btn-danger:hover {
  background: #f55;
  box-shadow: 0 4px 20px rgba(239, 68, 68, 0.3);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border);
}

.btn-ghost:hover {
  color: var(--text-primary);
  border-color: var(--text-muted);
}

.btn-sm {
  padding: 6px 16px;
  font-size: 0.85rem;
}

.btn-lg {
  padding: 14px 32px;
  font-size: 1.1rem;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none !important;
}

.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
  border-radius: var(--radius-btn);
}

/* ---------- Cards ---------- */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-card);
  padding: 24px;
  transition: all var(--transition);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
  border-color: var(--accent-muted);
}

.card-static {
  composes: card;
}

.card-static:hover {
  transform: none;
  box-shadow: none;
}

.card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

/* ---------- Forms ---------- */
.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-weight: 500;
  margin-bottom: 6px;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

input,
textarea,
select {
  width: 100%;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  color: var(--text-primary);
  padding: 12px 16px;
  border-radius: var(--radius-input);
  font-family: var(--font-ui);
  font-size: 0.95rem;
  transition: all var(--transition);
  outline: none;
}

input:focus,
textarea:focus,
select:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-glow);
}

input::placeholder,
textarea::placeholder {
  color: var(--text-muted);
}

.form-error {
  color: var(--danger);
  font-size: 0.85rem;
  margin-top: 6px;
  display: flex;
  align-items: center;
  gap: 4px;
}

/* ---------- Badges ---------- */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.badge-accent {
  background: var(--accent-muted);
  color: var(--accent);
}

.badge-secondary {
  background: rgba(124, 58, 237, 0.2);
  color: var(--secondary);
}

.badge-success {
  background: rgba(34, 197, 94, 0.2);
  color: var(--success);
}

.badge-danger {
  background: rgba(239, 68, 68, 0.2);
  color: var(--danger);
}

.badge-warning {
  background: rgba(245, 158, 11, 0.2);
  color: var(--warning);
}

/* ---------- Hero / Landing Page ---------- */
.hero {
  min-height: 80vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 24px 80px;
  background:
    radial-gradient(ellipse at 50% 0%, rgba(0, 212, 170, 0.08) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 50%, rgba(124, 58, 237, 0.05) 0%, transparent 50%);
  position: relative;
}

.hero h1 {
  font-size: 3.5rem;
  max-width: 800px;
  line-height: 1.15;
  margin-bottom: 20px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero .subtitle {
  font-size: 1.3rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 32px;
  line-height: 1.6;
}

.cta-buttons {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ---------- Features Section ---------- */
.features-section {
  padding: 80px 24px;
  max-width: 1200px;
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 48px;
}

.section-header h2 {
  margin-bottom: 12px;
}

.section-header p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  max-width: 600px;
  margin: 0 auto;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.feature-card {
  text-align: center;
  padding: 32px 24px;
}

.feature-icon {
  font-size: 2.5rem;
  color: var(--accent);
  margin-bottom: 16px;
}

.feature-card h3 {
  font-size: 1.2rem;
  margin-bottom: 8px;
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ---------- Courses Section ---------- */
.courses-section {
  padding: 80px 24px;
  max-width: 1200px;
  margin: 0 auto;
}

.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

.course-card {
  padding: 0;
  overflow: hidden;
  cursor: pointer;
}

.course-card-top {
  height: 6px;
}

.course-card-body {
  padding: 24px;
}

.course-card-icon {
  font-size: 2.5rem;
  margin-bottom: 16px;
}

.course-card-body h3 {
  font-size: 1.3rem;
  margin-bottom: 8px;
}

.course-card-body p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 16px;
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.course-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}

.course-price {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--accent);
}

/* ---------- Pricing Section ---------- */
.pricing-section {
  padding: 80px 24px;
  text-align: center;
  max-width: 900px;
  margin: 0 auto;
}

.pricing-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 24px;
  margin-top: 40px;
}

.pricing-card {
  padding: 40px 32px;
  text-align: center;
  position: relative;
}

.pricing-card.featured {
  border-color: var(--accent);
  box-shadow: 0 0 40px var(--accent-glow);
}

.pricing-card .price {
  font-size: 3rem;
  font-weight: 700;
  color: var(--accent);
  margin: 16px 0;
}

.pricing-card .price-label {
  color: var(--text-muted);
  font-size: 0.9rem;
}

.pricing-features {
  text-align: left;
  margin: 24px 0;
}

.pricing-features li {
  padding: 8px 0;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 10px;
}

.pricing-features li i {
  color: var(--accent);
  width: 20px;
}

/* ---------- Auth Pages ---------- */
.auth-container {
  max-width: 440px;
  margin: 0 auto;
  padding: calc(var(--nav-height) + 40px) 24px 40px;
  min-height: 100vh;
}

.auth-card {
  padding: 40px;
}

.auth-card:hover {
  transform: none;
}

.auth-title {
  text-align: center;
  margin-bottom: 32px;
}

.auth-title i {
  font-size: 2.5rem;
  color: var(--accent);
  margin-bottom: 12px;
  display: block;
}

.auth-title h2 {
  margin-bottom: 8px;
}

.auth-title p {
  color: var(--text-muted);
}

.auth-footer {
  text-align: center;
  margin-top: 20px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* ---------- Dashboard ---------- */
.dashboard {
  max-width: 1200px;
  margin: 0 auto;
  padding: calc(var(--nav-height) + 32px) 24px 40px;
}

.dashboard-header {
  margin-bottom: 40px;
}

.dashboard-header h1 {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 8px;
}

.dashboard-header h1 i {
  color: var(--accent);
}

.dashboard-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
  margin-top: 24px;
}

.stat-card {
  padding: 20px;
  display: flex;
  align-items: center;
  gap: 16px;
}

.stat-card:hover {
  transform: none;
}

.stat-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-btn);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
}

.stat-icon.accent {
  background: var(--accent-muted);
  color: var(--accent);
}

.stat-icon.secondary {
  background: rgba(124, 58, 237, 0.2);
  color: var(--secondary);
}

.stat-icon.success {
  background: rgba(34, 197, 94, 0.2);
  color: var(--success);
}

.stat-value {
  font-size: 1.5rem;
  font-weight: 700;
}

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

.section-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.section-title h2 {
  font-size: 1.4rem;
  display: flex;
  align-items: center;
  gap: 10px;
}

.section-title h2 i {
  color: var(--accent);
}

.my-courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 20px;
  margin-bottom: 40px;
}

.progress-card {
  padding: 24px;
}

.progress-card:hover {
  transform: none;
  box-shadow: none;
}

.progress-card-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}

.progress-card-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-btn);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
}

.progress-card-info h3 {
  font-size: 1.1rem;
  margin-bottom: 2px;
}

.progress-card-info p {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.progress-bar-container {
  background: var(--bg-elevated);
  border-radius: 10px;
  height: 10px;
  overflow: hidden;
  margin-bottom: 12px;
}

.progress-bar-fill {
  background: linear-gradient(90deg, var(--accent), var(--secondary));
  height: 100%;
  border-radius: 10px;
  transition: width 0.5s ease;
  min-width: 0;
}

.progress-details {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.course-status {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.course-status.active {
  color: var(--accent);
}

.course-status.completed {
  color: var(--success);
}

.course-status.expired {
  color: var(--danger);
}

.empty-state {
  text-align: center;
  padding: 60px 24px;
  color: var(--text-muted);
}

.empty-state i {
  font-size: 3rem;
  margin-bottom: 16px;
  color: var(--border);
}

.empty-state p {
  font-size: 1.1rem;
  margin-bottom: 20px;
}

/* ---------- Course Detail ---------- */
.course-detail {
  max-width: 900px;
  margin: 0 auto;
  padding: calc(var(--nav-height) + 32px) 24px 40px;
}

.course-header {
  display: flex;
  align-items: flex-start;
  gap: 24px;
  margin-bottom: 40px;
}

.course-icon-large {
  width: 80px;
  height: 80px;
  border-radius: var(--radius-card);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  flex-shrink: 0;
}

.course-info h1 {
  font-size: 2rem;
  margin-bottom: 8px;
}

.course-info p {
  color: var(--text-secondary);
  margin-bottom: 16px;
  line-height: 1.6;
}

.course-meta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-muted);
  font-size: 0.9rem;
}

.meta-item i {
  color: var(--accent);
}

.info-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 16px;
  margin-bottom: 40px;
}

.info-card {
  text-align: center;
  padding: 20px;
}

.info-card:hover {
  transform: none;
}

.info-card i {
  font-size: 1.5rem;
  color: var(--accent);
  margin-bottom: 8px;
}

.info-card h4 {
  margin-bottom: 4px;
}

.info-card p {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.curriculum-section {
  margin-bottom: 40px;
}

.week-card {
  margin-bottom: 12px;
  overflow: hidden;
}

.week-card:hover {
  transform: none;
}

.week-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  padding: 16px 20px;
  background: var(--bg-card);
  border-radius: var(--radius-card);
  transition: background var(--transition);
}

.week-header:hover {
  background: var(--bg-elevated);
}

.week-header h3 {
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  gap: 10px;
}

.week-header h3 i {
  color: var(--accent);
}

.week-header .chevron {
  transition: transform var(--transition);
  color: var(--text-muted);
}

.week-header.expanded .chevron {
  transform: rotate(180deg);
}

.week-days {
  display: none;
  padding: 8px 20px 16px;
}

.week-days.show {
  display: block;
}

.day-item {
  padding: 10px 16px;
  border-left: 2px solid var(--border);
  margin-left: 8px;
  margin-bottom: 4px;
  color: var(--text-secondary);
  font-size: 0.95rem;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
}

.day-item:hover {
  border-left-color: var(--accent);
  color: var(--text-primary);
  background: var(--accent-glow);
  border-radius: 0 var(--radius-btn) var(--radius-btn) 0;
}

.day-item i {
  color: var(--text-muted);
  font-size: 0.8rem;
}

.purchase-section {
  text-align: center;
  padding: 40px;
  border: 2px dashed var(--border);
  border-radius: var(--radius-card);
}

.purchase-section .price {
  font-size: 2.5rem;
  font-weight: 700;
  color: var(--accent);
  margin: 12px 0;
}

.purchase-section p {
  color: var(--text-muted);
  margin-bottom: 20px;
}

/* ---------- Learning Interface ---------- */
.learn-container {
  height: calc(100vh - var(--nav-height));
  margin-top: var(--nav-height);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.learn-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-nav);
  padding: 12px 24px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  gap: 16px;
}

.learn-header-left {
  display: flex;
  align-items: center;
  gap: 16px;
}

.learn-back {
  color: var(--text-muted);
  font-size: 1.1rem;
  cursor: pointer;
  transition: color var(--transition);
}

.learn-back:hover {
  color: var(--accent);
}

.learn-day-title {
  font-size: 1rem;
  font-weight: 600;
}

.learn-header-center {
  color: var(--text-muted);
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  gap: 6px;
}

.learn-header-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.learn-nav-btn {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-btn);
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

.learn-nav-btn:hover:not(:disabled) {
  border-color: var(--accent);
  color: var(--accent);
}

.learn-nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.learn-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  flex: 1;
  overflow: hidden;
}

/* Chat Panel */
.chat-panel {
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border-right: 1px solid var(--border);
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
}

.chat-messages::-webkit-scrollbar {
  width: 6px;
}

.chat-messages::-webkit-scrollbar-track {
  background: transparent;
}

.chat-messages::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

.message {
  margin-bottom: 16px;
  max-width: 90%;
  animation: fadeIn 0.3s ease;
}

.message.ai {
  margin-right: auto;
}

.message.user {
  margin-left: auto;
}

.message-bubble {
  padding: 16px;
  border-radius: 12px;
  line-height: 1.6;
  font-size: 0.95rem;
}

.message.ai .message-bubble {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px 12px 12px 0;
}

.message.user .message-bubble {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 12px 12px 0 12px;
}

.message-header {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
  font-weight: 600;
  font-size: 0.85rem;
}

.message.ai .message-header {
  color: var(--accent);
}

.message.user .message-header {
  color: var(--secondary);
}

.message-bubble p {
  margin-bottom: 8px;
}

.message-bubble p:last-child {
  margin-bottom: 0;
}

.message-bubble ul,
.message-bubble ol {
  margin: 8px 0;
  padding-left: 20px;
}

.message-bubble li {
  list-style: disc;
  margin-bottom: 4px;
  color: var(--text-secondary);
}

.message-bubble ol li {
  list-style: decimal;
}

.message-bubble h3 {
  font-size: 1.1rem;
  margin: 12px 0 8px;
  color: var(--accent);
}

.message-bubble h4 {
  font-size: 1rem;
  margin: 10px 0 6px;
}

.message-bubble pre {
  margin: 8px 0;
  background: var(--bg-body);
  border: 1px solid var(--border);
}

.message-bubble pre code {
  font-size: 0.85rem;
  color: var(--text-primary);
}

.message-bubble code {
  font-size: 0.85em;
}

/* Exercise card in chat */
.exercise-card {
  background: var(--bg-elevated);
  border-left: 3px solid var(--accent);
  padding: 16px;
  margin: 12px 0;
  border-radius: 0 var(--radius-btn) var(--radius-btn) 0;
}

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

.exercise-card h4 {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
  font-size: 1rem;
}

.exercise-card h4 i {
  color: var(--accent);
}

.exercise-card.completed h4 i {
  color: var(--success);
}

.exercise-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Typing indicator */
.typing-indicator {
  display: flex;
  gap: 4px;
  padding: 8px;
}

.typing-indicator span {
  width: 8px;
  height: 8px;
  background: var(--accent);
  border-radius: 50%;
  animation: typingBounce 1.4s ease-in-out infinite;
}

.typing-indicator span:nth-child(2) {
  animation-delay: 0.2s;
}

.typing-indicator span:nth-child(3) {
  animation-delay: 0.4s;
}

@keyframes typingBounce {
  0%, 60%, 100% { transform: translateY(0); opacity: 0.4; }
  30% { transform: translateY(-6px); opacity: 1; }
}

/* Chat Input */
.chat-input-area {
  padding: 16px;
  border-top: 1px solid var(--border);
  display: flex;
  gap: 8px;
}

.chat-input-area input {
  flex: 1;
}

.chat-input-area button {
  flex-shrink: 0;
}

/* Editor Panel */
.editor-panel {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.editor-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-nav);
  padding: 8px 16px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.editor-toolbar-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.editor-toolbar-left .editor-lang {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
}

.editor-toolbar-left .editor-lang i {
  color: var(--accent);
}

.editor-toolbar-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.code-editor-wrapper {
  flex: 1;
  overflow: hidden;
}

.code-editor-wrapper .CodeMirror {
  height: 100%;
  font-family: var(--font-code);
  font-size: 14px;
}

.output-panel {
  height: 200px;
  background: var(--bg-body);
  border-top: 1px solid var(--border);
  overflow-y: auto;
  padding: 12px 16px;
  font-family: var(--font-code);
  font-size: 0.85rem;
  flex-shrink: 0;
}

.output-panel::-webkit-scrollbar {
  width: 6px;
}

.output-panel::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 3px;
}

.output-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.output-header span {
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.output-content {
  color: var(--text-secondary);
  white-space: pre-wrap;
  word-break: break-word;
}

.output-content.error {
  color: var(--danger);
}

.output-content.success {
  color: var(--success);
}

/* ---------- Project Page ---------- */
.project-container {
  height: calc(100vh - var(--nav-height));
  margin-top: var(--nav-height);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.project-header {
  background: var(--bg-nav);
  padding: 16px 24px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
}

.project-header-left {
  display: flex;
  align-items: center;
  gap: 16px;
}

.project-requirements {
  padding: 20px 24px;
  background: var(--bg-card);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  max-height: 200px;
  overflow-y: auto;
}

.project-requirements h3 {
  font-size: 1.1rem;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.project-requirements h3 i {
  color: var(--accent);
}

.project-requirements p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
}

.project-editor {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.project-editor .code-editor-wrapper {
  flex: 1;
}

.project-description-area {
  padding: 16px 24px;
  border-top: 1px solid var(--border);
  background: var(--bg-nav);
}

.project-description-area label {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 8px;
  display: block;
}

.project-description-area textarea {
  height: 80px;
  resize: none;
}

.project-results {
  padding: 24px;
  background: var(--bg-card);
  border-top: 1px solid var(--border);
}

.project-results h3 {
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.project-score {
  font-size: 3rem;
  font-weight: 700;
  text-align: center;
  margin: 12px 0;
}

.project-score.passed {
  color: var(--success);
}

.project-score.failed {
  color: var(--danger);
}

.project-feedback {
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 16px;
}

/* ---------- Certificate ---------- */
.certificate-container {
  max-width: 800px;
  margin: 0 auto;
  padding: calc(var(--nav-height) + 40px) 24px 40px;
}

.certificate {
  background: var(--bg-card);
  border: 2px solid var(--accent);
  border-radius: 16px;
  padding: 60px;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.certificate::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--secondary), var(--accent));
}

.certificate::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--accent), var(--secondary), var(--accent));
}

.certificate-badge {
  width: 80px;
  height: 80px;
  margin: 0 auto 24px;
  background: var(--accent-muted);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

.certificate-badge i {
  font-size: 2.5rem;
  color: var(--accent);
}

.certificate-label {
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 3px;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.certificate h1 {
  font-size: 2rem;
  margin-bottom: 24px;
  color: var(--accent);
}

.certificate-text {
  font-size: 1.1rem;
  color: var(--text-secondary);
  margin-bottom: 8px;
  line-height: 1.6;
}

.certificate-student {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 16px 0;
}

.certificate-course {
  font-size: 1.3rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: 24px;
}

.certificate-details {
  display: flex;
  justify-content: center;
  gap: 40px;
  margin: 32px 0;
  padding: 20px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
}

.certificate-detail {
  text-align: center;
}

.certificate-detail-label {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.certificate-detail-value {
  font-size: 1.1rem;
  font-weight: 600;
}

.certificate-id {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 24px;
  font-family: var(--font-code);
}

.certificate-actions {
  margin-top: 24px;
  display: flex;
  justify-content: center;
  gap: 12px;
}

/* ---------- Toast Notifications ---------- */
#toast-container {
  position: fixed;
  top: 80px;
  right: 24px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  padding: 16px 20px;
  border-radius: var(--radius-btn);
  min-width: 300px;
  max-width: 420px;
  display: flex;
  align-items: center;
  gap: 12px;
  animation: slideIn 0.3s ease;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.3);
}

.toast.success {
  border-left-color: var(--success);
}

.toast.success i {
  color: var(--success);
}

.toast.error {
  border-left-color: var(--danger);
}

.toast.error i {
  color: var(--danger);
}

.toast.info {
  border-left-color: var(--accent);
}

.toast.info i {
  color: var(--accent);
}

.toast.warning {
  border-left-color: var(--warning);
}

.toast.warning i {
  color: var(--warning);
}

.toast i {
  font-size: 1.2rem;
  flex-shrink: 0;
}

.toast-message {
  flex: 1;
  font-size: 0.9rem;
  color: var(--text-primary);
}

.toast-close {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px;
  font-size: 0.9rem;
  transition: color var(--transition);
}

.toast-close:hover {
  color: var(--text-primary);
}

/* ---------- Loading ---------- */
.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.loading-overlay {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 200px;
  width: 100%;
}

.loading-page {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: calc(100vh - var(--nav-height));
  padding-top: var(--nav-height);
}

/* ---------- Animations ---------- */
@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

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

@keyframes slideIn {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

.animate-fade {
  animation: fadeIn 0.4s ease;
}

.animate-slide {
  animation: slideUp 0.4s ease;
}

/* ---------- Scrollbar ---------- */
::-webkit-scrollbar {
  width: 8px;
}

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

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* ---------- Utilities ---------- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.flex {
  display: flex;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.gap-8 { gap: 8px; }
.gap-12 { gap: 12px; }
.gap-16 { gap: 16px; }
.gap-24 { gap: 24px; }

.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-8 { margin-bottom: 8px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }

.hidden { display: none !important; }

/* ---------- Print Styles (Certificate) ---------- */
@media print {
  body {
    background: #fff;
    color: #000;
  }

  .navbar,
  .footer,
  .certificate-actions,
  #toast-container {
    display: none !important;
  }

  .certificate-container {
    padding: 0;
    margin: 0;
  }

  .certificate {
    border-color: #333;
    box-shadow: none;
    padding: 40px;
  }

  .certificate-badge i,
  .certificate h1,
  .certificate-course {
    color: #333;
  }
}

/* ---------- Responsive ---------- */
@media (max-width: 768px) {
  .hamburger {
    display: block;
  }

  .nav-right {
    display: none;
    position: absolute;
    top: var(--nav-height);
    left: 0;
    right: 0;
    background: var(--bg-nav);
    border-bottom: 1px solid var(--border);
    padding: 16px 24px;
    flex-direction: column;
    gap: 16px;
  }

  .nav-right.open {
    display: flex;
  }

  .nav-links {
    flex-direction: column;
    width: 100%;
  }

  .nav-link {
    width: 100%;
    padding: 12px 16px;
  }

  .nav-auth {
    width: 100%;
  }

  .nav-auth > div {
    width: 100%;
    justify-content: center;
  }

  .hero h1 {
    font-size: 2.2rem;
  }

  .hero .subtitle {
    font-size: 1.1rem;
  }

  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

  .my-courses-grid {
    grid-template-columns: 1fr;
  }

  .course-header {
    flex-direction: column;
  }

  .learn-layout {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr 1fr;
  }

  .chat-panel {
    border-right: none;
    border-bottom: 1px solid var(--border);
  }

  .learn-header {
    padding: 8px 16px;
    flex-wrap: wrap;
    gap: 8px;
  }

  .learn-day-title {
    font-size: 0.9rem;
  }

  .certificate {
    padding: 32px 20px;
  }

  .certificate-details {
    flex-direction: column;
    gap: 16px;
  }

  .pricing-cards {
    grid-template-columns: 1fr;
  }

  .dashboard-stats {
    grid-template-columns: 1fr;
  }

  .info-cards {
    grid-template-columns: repeat(2, 1fr);
  }
}

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

  .hero h1 {
    font-size: 1.8rem;
  }

  .hero .subtitle {
    font-size: 1rem;
  }

  .cta-buttons {
    flex-direction: column;
    align-items: center;
  }

  .auth-card {
    padding: 24px;
  }

  .course-meta {
    flex-direction: column;
  }

  .info-cards {
    grid-template-columns: 1fr;
  }

  .output-panel {
    height: 150px;
  }
}

/* ---------- Footer ---------- */
.footer {
  background: var(--bg-nav);
  border-top: 1px solid var(--border);
  padding: 24px;
  text-align: center;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

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

.footer-tagline {
  display: flex;
  align-items: center;
  gap: 6px;
}

.footer-tagline i {
  color: var(--accent);
}

/* Hide footer on learning pages */
body.hide-footer .footer {
  display: none;
}