/* ============================================================
   AI Interview Assistant — Premium Dark Design System
   ============================================================ */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

:root {
  --bg-primary: #0f172a;
  --bg-secondary: #111827;
  --bg-card: #1e293b;
  --bg-card-hover: #243044;
  --bg-elevated: #0b1220;
  --accent-blue: #3b82f6;
  --accent-blue-hover: #2563eb;
  --accent-purple: #8b5cf6;
  --accent-purple-hover: #7c3aed;
  --gradient-primary: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
  --gradient-glow: linear-gradient(135deg, rgba(59, 130, 246, 0.4), rgba(139, 92, 246, 0.4));
  --text-primary: #f8fafc;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --border-subtle: rgba(148, 163, 184, 0.12);
  --border-accent: rgba(139, 92, 246, 0.35);
  --shadow-sm: 0 4px 16px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 8px 32px rgba(0, 0, 0, 0.35);
  --shadow-glow: 0 0 40px rgba(59, 130, 246, 0.15);
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.25rem;
  --radius-full: 9999px;
  --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --nav-height: 4rem;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="light"] {
  --bg-primary: #f1f5f9;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-card-hover: #f8fafc;
  --bg-elevated: #e2e8f0;
  --text-primary: #0f172a;
  --text-muted: #475569;
  --text-dim: #64748b;
  --border-subtle: rgba(15, 23, 42, 0.1);
  --border-accent: rgba(59, 130, 246, 0.35);
  --shadow-sm: 0 4px 16px rgba(15, 23, 42, 0.08);
  --shadow-md: 0 8px 32px rgba(15, 23, 42, 0.12);
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--text-primary);
  background: var(--bg-primary);
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

/* ========== Layout pages ========== */
.page-landing,
.page-device-setup,
.page-history,
.page-settings {
  background: var(--bg-primary);
  background-image:
    radial-gradient(ellipse 80% 50% at 20% -10%, rgba(59, 130, 246, 0.12), transparent),
    radial-gradient(ellipse 60% 40% at 90% 100%, rgba(139, 92, 246, 0.1), transparent);
}

/* ========== Glass & cards ========== */
.glass {
  background: rgba(30, 41, 59, 0.65);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-md);
}

.glass-dark,
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.card:hover {
  border-color: var(--border-accent);
}

.card--glow:hover {
  box-shadow: var(--shadow-md), var(--shadow-glow);
}

/* ========== Navbar ========== */
.site-navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: var(--nav-height);
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
}

.navbar-inner {
  max-width: 80rem;
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  text-decoration: none;
  color: var(--text-primary);
}

.navbar-logo {
  width: 2.5rem;
  height: 2.5rem;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-primary);
  font-size: 1.1rem;
  color: #fff;
  box-shadow: 0 4px 20px rgba(59, 130, 246, 0.4);
}

.navbar-title {
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -0.02em;
}

.navbar-title span {
  display: block;
  font-size: 0.65rem;
  font-weight: 500;
  color: var(--text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.navbar-actions {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.nav-link-btn {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.nav-user-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  cursor: default;
  color: var(--text-muted) !important;
  font-size: 0.85rem !important;
}

/* ========== Buttons ========== */
.btn,
.glass-btn,
.nav-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.55rem 1.15rem;
  border-radius: var(--radius-full);
  font-family: var(--font);
  font-size: 0.875rem;
  font-weight: 600;
  line-height: 1.2;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition);
  text-decoration: none;
  white-space: nowrap;
}

.glass-btn,
.nav-btn {
  background: var(--bg-card);
  border-color: var(--border-subtle);
  color: var(--text-primary) !important;
}

.glass-btn:hover,
.nav-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-accent);
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(59, 130, 246, 0.2);
}

.nav-btn-primary,
.btn--primary {
  background: var(--gradient-primary) !important;
  border-color: transparent !important;
  color: #fff !important;
  box-shadow: 0 4px 20px rgba(59, 130, 246, 0.35);
}

.nav-btn-primary:hover,
.btn--primary:hover {
  filter: brightness(1.08);
  box-shadow: 0 6px 28px rgba(139, 92, 246, 0.45);
  transform: translateY(-2px);
}

.btn--secondary {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  padding: 0.65rem 1.25rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
}

.btn--secondary:hover {
  border-color: var(--accent-blue);
  background: var(--bg-card-hover);
  box-shadow: 0 0 20px rgba(59, 130, 246, 0.15);
}

.btn--danger,
.btn-end-interview {
  background: linear-gradient(135deg, #ef4444, #dc2626) !important;
  border: none !important;
  color: #fff !important;
  padding: 0.7rem 1.5rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  box-shadow: 0 4px 20px rgba(239, 68, 68, 0.3);
}

.btn--danger:hover,
.btn-end-interview:hover {
  filter: brightness(1.08);
  transform: translateY(-1px);
  box-shadow: 0 6px 28px rgba(239, 68, 68, 0.4);
}

.btn--device {
  width: 100%;
  padding: 0.75rem 1.25rem;
  border-radius: var(--radius-full);
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: all var(--transition);
  color: #fff !important;
  background: var(--gradient-primary);
  box-shadow: 0 4px 16px rgba(59, 130, 246, 0.3);
}

.btn--device:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(139, 92, 246, 0.4);
}

.btn--device-outline {
  width: 100%;
  margin-top: 0.5rem;
  padding: 0.55rem 1rem;
  border-radius: var(--radius-full);
  font-weight: 500;
  font-size: 0.85rem;
  cursor: pointer;
  background: transparent;
  border: 1px solid var(--border-subtle);
  color: var(--text-muted) !important;
  transition: all var(--transition);
}

.btn--device-outline:hover {
  border-color: var(--accent-blue);
  color: var(--text-primary) !important;
  background: rgba(59, 130, 246, 0.08);
}

.btn-start-interview {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.65rem;
  padding: 1rem 2.25rem;
  border: none;
  border-radius: var(--radius-full);
  font-size: 1.05rem;
  font-weight: 700;
  font-family: var(--font);
  color: #fff !important;
  cursor: pointer;
  background: var(--gradient-primary);
  box-shadow: 0 8px 32px rgba(59, 130, 246, 0.4);
  transition: all var(--transition);
}

.btn-start-interview--enabled:hover {
  transform: scale(1.03) translateY(-2px);
  box-shadow: 0 12px 40px rgba(139, 92, 246, 0.5);
}

.btn-start-interview--locked,
.btn-start-interview:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none !important;
  filter: grayscale(0.2);
}

.glass-btn-secondary {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  font-weight: 600;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.glass-btn-secondary:hover {
  border-color: var(--accent-purple);
  background: var(--bg-card-hover);
}

/* ========== Landing ========== */
.landing-main {
  min-height: 100vh;
  padding: calc(var(--nav-height) + 2rem) 1.25rem 3rem;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.hero-glow {
  position: absolute;
  width: 24rem;
  height: 24rem;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.25;
  pointer-events: none;
}

.hero-glow--left { background: var(--accent-blue); top: 5%; left: -8%; }
.hero-glow--right { background: var(--accent-purple); bottom: 0; right: -8%; }

.hero-card {
  max-width: 56rem;
  width: 100%;
  padding: 2.5rem 2rem;
  border-radius: var(--radius-xl);
  text-align: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent-purple);
  background: rgba(139, 92, 246, 0.15);
  border: 1px solid var(--border-accent);
  margin-bottom: 1.25rem;
}

.hero-title {
  font-size: clamp(2rem, 5vw, 3.25rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin: 0 0 1rem;
  background: linear-gradient(135deg, #fff 0%, #cbd5e1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 38rem;
  margin: 0 auto 2rem;
}

.feature-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr));
  gap: 1rem;
  margin-bottom: 1.75rem;
  text-align: left;
}

.feature-card {
  padding: 1.25rem;
  border-radius: var(--radius-lg);
}

.feature-card i {
  font-size: 1.4rem;
  color: var(--accent-blue);
}

.feature-card h3 {
  font-size: 0.95rem;
  font-weight: 700;
  margin: 0.65rem 0 0.25rem;
}

.feature-card p {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin: 0;
}

.hero-cta {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

.start-interview-wrap { position: relative; display: inline-flex; flex-direction: column; align-items: center; }

.start-interview-tooltip {
  margin: 0.5rem 0 0;
  font-size: 0.8rem;
  color: #fbbf24;
  font-weight: 500;
}

/* ========== Interview prep selects ========== */
.interview-prep {
  padding: 1.25rem;
  border-radius: var(--radius-lg);
  margin-bottom: 1.25rem;
  text-align: left;
}

.interview-prep__title {
  font-size: 0.9rem;
  font-weight: 700;
  margin: 0 0 1rem;
  color: var(--text-primary);
}

.interview-prep__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

@media (max-width: 560px) {
  .interview-prep__grid { grid-template-columns: 1fr; }
}

.interview-prep__field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-muted);
}

.interview-prep__select {
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  border-radius: var(--radius-md);
  padding: 0.6rem 0.85rem;
  font-family: var(--font);
  font-size: 0.875rem;
  cursor: pointer;
  transition: border-color var(--transition);
}

.interview-prep__select:focus {
  outline: none;
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

/* ========== Device setup ========== */
.device-setup-main {
  min-height: 100vh;
  padding: calc(var(--nav-height) + 1.5rem) 1rem 2rem;
}

.device-setup-main .glass.rounded-3xl {
  border-radius: var(--radius-xl);
  padding: 2rem 1.5rem;
  max-width: 56rem;
  margin: 0 auto;
}

@media (min-width: 768px) {
  .device-setup-main .glass.rounded-3xl { padding: 2.5rem 2.5rem; }
}

.setup-page-title {
  font-size: clamp(1.75rem, 4vw, 2.25rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin: 0 0 0.5rem;
}

.setup-page-subtitle {
  color: var(--text-muted);
  font-size: 1rem;
  margin: 0;
}

.device-card {
  padding: 1.5rem;
  border-radius: var(--radius-lg);
}

.device-card__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
}

.device-card__title {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 1rem;
  font-weight: 700;
  margin: 0;
}

.device-card__title i {
  color: var(--accent-blue);
}

.device-card__status {
  color: var(--text-muted);
  font-size: 0.875rem;
  margin-bottom: 1rem;
}

.video-preview-wrap {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  aspect-ratio: 16/10;
  background: #000;
  border: 1px solid var(--border-subtle);
  margin-bottom: 1rem;
}

.video-preview-wrap video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.video-preview-wrap--speaking {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.3), 0 0 30px rgba(59, 130, 246, 0.2);
}

/* ========== Modals / Auth ========== */
.modal-backdrop,
.auth-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 200;
  background: rgba(2, 6, 23, 0.75);
  backdrop-filter: blur(8px);
  align-items: center;
  justify-content: center;
  padding: 1rem;
}

.modal-backdrop.modal-open,
.auth-modal[aria-hidden="false"] {
  display: flex;
}

.modal-card,
.auth-modal__panel,
.language-modal-panel {
  width: 100%;
  max-width: 28rem;
  padding: 2rem 1.75rem;
  border-radius: var(--radius-xl);
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  box-shadow: var(--shadow-md);
  animation: modal-in 0.35s ease;
}

@keyframes modal-in {
  from { opacity: 0; transform: translateY(16px) scale(0.98); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-close,
.auth-modal__close {
  position: absolute;
  top: 1rem;
  right: 1rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  width: 2rem;
  height: 2rem;
  border-radius: var(--radius-full);
  font-size: 1.25rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}

.modal-close:hover,
.auth-modal__close:hover {
  color: var(--text-primary);
  border-color: var(--border-accent);
}

.modal-title,
.auth-modal__title {
  font-size: 1.5rem;
  font-weight: 800;
  margin: 0 0 0.35rem;
  letter-spacing: -0.02em;
}

.modal-subtitle,
.auth-modal__subtitle {
  color: var(--text-muted);
  font-size: 0.875rem;
  margin: 0 0 1.5rem;
}

.auth-form { display: flex; flex-direction: column; gap: 0.35rem; }

.auth-label {
  color: var(--text-muted);
  font-size: 0.8rem;
  font-weight: 600;
  margin-top: 0.5rem;
}

.auth-input {
  width: 100%;
  padding: 0.7rem 0.9rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 0.95rem;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.auth-input::placeholder { color: var(--text-dim); }

.auth-input:focus {
  outline: none;
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.auth-error {
  color: #f87171;
  font-size: 0.85rem;
  min-height: 1.25rem;
  margin: 0.25rem 0;
}

.modal-footer-text {
  text-align: center;
  margin-top: 1.25rem;
  font-size: 0.875rem;
  color: var(--text-muted);
}

.modal-footer-text a {
  color: var(--accent-blue);
  font-weight: 600;
  text-decoration: none;
}

.modal-footer-text a:hover { text-decoration: underline; }

.auth-forgot-password {
  text-align: right;
  margin-top: 0.5rem;
  margin-bottom: 1rem;
}

.auth-forgot-password a {
  color: var(--accent-blue);
  font-size: 0.875rem;
  font-weight: 500;
  text-decoration: none;
  transition: color var(--transition);
}

.auth-forgot-password a:hover {
  color: var(--accent-blue-hover);
  text-decoration: underline;
}

.auth-success {
  color: #10b981;
  font-size: 0.875rem;
  margin: 0.5rem 0;
  text-align: center;
}

/* Language modal */
.language-options { display: flex; flex-direction: column; gap: 0.5rem; margin: 1rem 0 1.25rem; }

.language-option {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-md);
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition);
}

.language-option:has(input:checked) {
  border-color: var(--accent-purple);
  background: rgba(139, 92, 246, 0.12);
}

/* Voice test panel */
.voice-test-panel { padding: 1.25rem; border-radius: var(--radius-lg); margin-bottom: 1.25rem; }

.voice-test-buttons { display: flex; flex-wrap: wrap; gap: 0.5rem; margin-bottom: 0.5rem; }

.voice-test-btn {
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-accent);
  background: rgba(59, 130, 246, 0.12);
  color: var(--text-primary);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  font-family: var(--font);
  transition: all var(--transition);
}

.voice-test-btn:hover {
  background: rgba(59, 130, 246, 0.25);
  box-shadow: 0 0 20px rgba(59, 130, 246, 0.2);
}

.voice-test-hint { margin: 0; font-size: 0.75rem; color: var(--text-dim); }

/* Animations */
.animate-fade-in { animation: fade-in 0.6s ease; }

@keyframes fade-in {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 20px rgba(59, 130, 246, 0.2); }
  50% { box-shadow: 0 0 40px rgba(139, 92, 246, 0.45); }
}

/* History page base */
.page-history .history-main {
  padding: calc(var(--nav-height) + 2rem) 1rem 3rem;
  max-width: 56rem;
  margin: 0 auto;
}

.history-container {
  padding: 1.75rem;
  border-radius: var(--radius-xl);
}

.history-header h1 {
  font-size: 1.5rem;
  font-weight: 800;
  margin: 0 0 0.35rem;
  letter-spacing: -0.02em;
}

.history-header p { color: var(--text-muted); margin: 0 0 1.5rem; }

.history-card {
  padding: 1.25rem;
  border-radius: var(--radius-lg);
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  cursor: pointer;
  transition: all var(--transition);
  margin-bottom: 0.75rem;
}

.history-card:hover {
  border-color: var(--border-accent);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.history-card__mode { color: var(--accent-purple); font-weight: 700; font-size: 0.9rem; }
.history-card__date { color: var(--text-dim); font-size: 0.8rem; }
.history-card__meta, .history-card__scores {
  display: flex; flex-wrap: wrap; gap: 0.75rem;
  font-size: 0.8rem; color: var(--text-muted); margin: 0.5rem 0;
}
.history-card__summary { color: var(--text-muted); font-size: 0.85rem; margin: 0.5rem 0 0; line-height: 1.5; }

.history-score-pill {
  background: rgba(59, 130, 246, 0.12);
  border: 1px solid var(--border-accent);
  border-radius: var(--radius-full);
  padding: 0.35rem 0.85rem;
  font-size: 0.8rem;
  color: var(--text-primary);
}

.history-back-btn {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  border-radius: var(--radius-full);
  padding: 0.45rem 1rem;
  cursor: pointer;
  font-family: var(--font);
  font-weight: 600;
  margin-bottom: 1rem;
  transition: all var(--transition);
}

.history-back-btn:hover { border-color: var(--accent-blue); }

.history-empty, .history-loading, .history-error {
  text-align: center;
  color: var(--text-muted);
  padding: 2rem 1rem;
}

.history-detail.is-hidden { display: none; }

.history-section h3 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--accent-purple);
  margin: 0 0 0.5rem;
}

.history-turn {
  padding: 0.85rem;
  border-radius: var(--radius-md);
  background: var(--bg-elevated);
  border: 1px solid var(--border-subtle);
  margin-bottom: 0.5rem;
}

.history-turn__q { color: var(--accent-blue); margin: 0 0 0.35rem; font-size: 0.9rem; }
.history-turn__a { color: var(--text-primary); margin: 0; font-size: 0.9rem; }