/* ==========================================================================
   Analogy Tutor - Modern Design System & Stylesheet
   ========================================================================== */

:root {
  /* Color Palette - Deep Futuristic Obsidian & Cyberpunk Pastels */
  --bg-primary: #090D16;
  --bg-secondary: #0F172A;
  --bg-tertiary: #162038;
  --bg-glass: rgba(18, 26, 47, 0.75);
  --bg-card: rgba(23, 33, 58, 0.85);
  --bg-card-hover: rgba(30, 44, 76, 0.95);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(99, 102, 241, 0.35);
  --border-accent: rgba(6, 182, 212, 0.4);

  /* Brand Accents */
  --accent-indigo: #6366F1;
  --accent-indigo-light: #818CF8;
  --accent-cyan: #06B6D4;
  --accent-cyan-light: #22D3EE;
  --accent-emerald: #10B981;
  --accent-emerald-light: #34D399;
  --accent-amber: #F59E0B;
  --accent-amber-light: #FBBF24;
  --accent-rose: #F43F5E;
  --accent-purple: #A855F7;

  /* Text Colors */
  --text-primary: #F8FAFC;
  --text-secondary: #94A3B8;
  --text-muted: #64748B;
  --text-inverse: #090D16;

  /* Typography */
  --font-heading: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-body: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'Fira Code', monospace;

  /* Shadows & Glows */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 24px rgba(99, 102, 241, 0.25);
  --shadow-glow-cyan: 0 0 20px rgba(6, 182, 212, 0.3);
  --shadow-glow-emerald: 0 0 20px rgba(16, 185, 129, 0.3);

  /* Layout */
  --sidebar-width: 320px;
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-pill: 9999px;
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html, body {
  width: 100%;
  height: 100%;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.6;
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}

/* Background Ambient Glow */
body::before {
  content: '';
  position: fixed;
  top: -20%;
  left: 20%;
  width: 60vw;
  height: 60vh;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.12) 0%, rgba(6, 182, 212, 0.05) 50%, transparent 80%);
  pointer-events: none;
  z-index: 0;
}

body::after {
  content: '';
  position: fixed;
  bottom: -20%;
  right: 10%;
  width: 50vw;
  height: 50vh;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(168, 85, 247, 0.1) 0%, transparent 70%);
  pointer-events: none;
  z-index: 0;
}

/* Main Layout Grid */
.app-layout {
  display: flex;
  width: 100vw;
  height: 100vh;
  position: relative;
  z-index: 1;
}

/* ==========================================================================
   Sidebar Styling
   ========================================================================== */
.sidebar {
  width: var(--sidebar-width);
  height: 100%;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-subtle);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  overflow-y: auto;
  padding: 1.5rem 1.25rem;
  gap: 1.5rem;
  transition: transform var(--transition-smooth);
}

.sidebar::-webkit-scrollbar {
  width: 6px;
}
.sidebar::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 3px;
}

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

.brand-badge {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.brand-avatar {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  object-fit: cover;
  border: 2px solid var(--accent-indigo);
  box-shadow: 0 0 14px rgba(99, 102, 241, 0.4);
}

.brand-title {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  background: linear-gradient(135deg, #FFF 20%, var(--accent-cyan-light) 70%, var(--accent-indigo-light) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: -0.02em;
}

.brand-tagline {
  font-size: 0.75rem;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 600;
}

.sidebar-section {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.section-label {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-hint {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Theme Pills Grid */
.theme-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.5rem;
}

.theme-pill {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.75rem;
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: left;
}

.theme-pill:hover {
  background: rgba(99, 102, 241, 0.15);
  border-color: var(--border-glow);
  color: var(--text-primary);
  transform: translateY(-1px);
}

.theme-pill.active {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.3) 0%, rgba(6, 182, 212, 0.2) 100%);
  border-color: var(--accent-cyan);
  color: #FFF;
  box-shadow: 0 0 12px rgba(6, 182, 212, 0.25);
}

.pill-icon {
  font-size: 1.1rem;
}

.pill-label {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Styled Select */
.styled-select, .styled-input {
  width: 100%;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  padding: 0.65rem 0.85rem;
  font-family: var(--font-body);
  font-size: 0.9rem;
  outline: none;
  transition: border-color var(--transition-fast);
}

.styled-select:focus, .styled-input:focus {
  border-color: var(--accent-indigo);
  box-shadow: 0 0 10px rgba(99, 102, 241, 0.3);
}

/* Quick Prompts */
.quick-prompts-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.quick-prompt-btn {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.55rem 0.75rem;
  text-align: left;
  cursor: pointer;
  transition: all var(--transition-fast);
  color: var(--text-primary);
  font-size: 0.82rem;
}

.quick-prompt-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-accent);
  transform: translateX(3px);
}

.qp-tag {
  font-size: 0.65rem;
  font-weight: 700;
  text-transform: uppercase;
  padding: 0.2rem 0.45rem;
  border-radius: 4px;
  letter-spacing: 0.05em;
  flex-shrink: 0;
}

.qp-tag.math { background: rgba(99, 102, 241, 0.25); color: var(--accent-indigo-light); }
.qp-tag.bio { background: rgba(16, 185, 129, 0.25); color: var(--accent-emerald-light); }
.qp-tag.phys { background: rgba(245, 158, 11, 0.25); color: var(--accent-amber-light); }
.qp-tag.chem { background: rgba(168, 85, 247, 0.25); color: #C084FC; }
.qp-tag.code { background: rgba(6, 182, 212, 0.25); color: var(--accent-cyan-light); }

.qp-text {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* Pedagogy Guarantee Box */
.pedagogy-card {
  background: rgba(15, 23, 42, 0.6);
  border: 1px dashed var(--border-glow);
  border-radius: var(--radius-sm);
  padding: 0.85rem;
  font-size: 0.8rem;
}

.pedagogy-title {
  font-weight: 700;
  color: var(--accent-indigo-light);
  margin-bottom: 0.5rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.pedagogy-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  color: var(--text-secondary);
}

.pedagogy-list li strong {
  color: var(--text-primary);
}

/* Sidebar Footer */
.sidebar-footer {
  margin-top: auto;
  padding-top: 1rem;
}

/* ==========================================================================
   Main Content & Navbar
   ========================================================================== */
.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  height: 100%;
  position: relative;
  overflow: hidden;
  background: transparent;
}

/* Top Nav */
.top-nav {
  height: 64px;
  background: rgba(15, 23, 42, 0.7);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.5rem;
  flex-shrink: 0;
  z-index: 10;
}

.nav-left {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.page-title-group {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.page-title {
  font-family: var(--font-heading);
  font-size: 1.35rem;
  font-weight: 700;
  color: #FFF;
}

.mode-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  background: rgba(16, 185, 129, 0.15);
  border: 1px solid rgba(16, 185, 129, 0.35);
  color: var(--accent-emerald-light);
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-pill);
}

.mode-badge.gemini-mode {
  background: rgba(99, 102, 241, 0.2);
  border-color: var(--accent-indigo);
  color: var(--accent-indigo-light);
}

.status-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: currentColor;
  box-shadow: 0 0 8px currentColor;
  animation: pulse-dot 2s infinite ease-in-out;
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.8); }
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.stats-badge {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-pill);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--accent-amber-light);
}

.badge-label {
  color: var(--text-secondary);
  font-weight: 500;
}

/* ==========================================================================
   Chat Messages Feed
   ========================================================================== */
.chat-container {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  scroll-behavior: smooth;
}

.chat-container::-webkit-scrollbar {
  width: 8px;
}
.chat-container::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.12);
  border-radius: 4px;
}

.messages-feed {
  max-width: 920px;
  width: 100%;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  padding-bottom: 1rem;
}

/* Welcome Hero Card */
.welcome-hero-card {
  background: linear-gradient(135deg, rgba(23, 33, 58, 0.85) 0%, rgba(15, 23, 42, 0.95) 100%);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: 2rem;
  display: flex;
  gap: 1.75rem;
  align-items: flex-start;
  box-shadow: var(--shadow-glow);
  position: relative;
  overflow: hidden;
  animation: fade-in-up 0.5s ease;
}

.welcome-hero-card::after {
  content: '';
  position: absolute;
  top: 0;
  right: 0;
  width: 250px;
  height: 250px;
  background: radial-gradient(circle, rgba(99, 102, 241, 0.15) 0%, transparent 70%);
  pointer-events: none;
}

.hero-avatar-wrapper {
  position: relative;
  flex-shrink: 0;
}

.hero-avatar {
  width: 84px;
  height: 84px;
  border-radius: 20px;
  object-fit: cover;
  border: 3px solid var(--accent-cyan);
  box-shadow: var(--shadow-glow-cyan);
}

.hero-content {
  flex: 1;
}

.hero-content h2 {
  font-family: var(--font-heading);
  font-size: 1.45rem;
  font-weight: 700;
  margin-bottom: 0.65rem;
  color: #FFF;
}

.hero-content p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 1.25rem;
}

.hero-steps {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(190px, 1fr));
  gap: 0.85rem;
  margin-bottom: 1.25rem;
}

.hero-step {
  background: rgba(11, 15, 25, 0.6);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.75rem;
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
}

.step-num {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--accent-indigo);
  color: #FFF;
  font-size: 0.75rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-text {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.hero-cta-hint {
  font-size: 0.85rem;
  color: var(--accent-cyan-light);
  font-weight: 600;
}

/* Chat Message Styles */
.message-row {
  display: flex;
  gap: 1rem;
  animation: fade-in-up 0.3s ease;
}

.message-row.user {
  justify-content: flex-end;
}

.message-avatar {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  object-fit: cover;
  flex-shrink: 0;
}

.message-avatar.tutor {
  border: 2px solid var(--accent-indigo);
  box-shadow: 0 0 10px rgba(99, 102, 241, 0.3);
}

.user-avatar-icon {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--accent-indigo) 0%, var(--accent-purple) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #FFF;
  font-size: 0.9rem;
  flex-shrink: 0;
}

.message-body {
  max-width: 85%;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.message-row.user .message-body {
  align-items: flex-end;
}

.user-bubble {
  background: linear-gradient(135deg, var(--accent-indigo) 0%, #4F46E5 100%);
  color: #FFF;
  padding: 0.85rem 1.15rem;
  border-radius: 18px 18px 4px 18px;
  font-size: 0.95rem;
  line-height: 1.55;
  box-shadow: var(--shadow-sm);
  word-break: break-word;
}

/* Structured Tutor Card Container */
.tutor-response-container {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  width: 100%;
}

.tutor-praise-banner {
  background: rgba(16, 185, 129, 0.12);
  border-left: 3px solid var(--accent-emerald);
  padding: 0.65rem 1rem;
  border-radius: var(--radius-sm);
  color: var(--accent-emerald-light);
  font-weight: 600;
  font-size: 0.9rem;
}

/* Analogy Card */
.analogy-card {
  background: var(--bg-card);
  border: 1px solid rgba(245, 158, 11, 0.3);
  border-radius: var(--radius-md);
  padding: 1.15rem 1.25rem;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.25);
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.analogy-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-amber) 0%, var(--accent-cyan) 100%);
}

.card-badge-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.65rem;
}

.card-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-heading);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.25rem 0.6rem;
  border-radius: 6px;
}

.card-badge.analogy {
  background: rgba(245, 158, 11, 0.2);
  color: var(--accent-amber-light);
}

.card-badge.connection {
  background: rgba(99, 102, 241, 0.2);
  color: var(--accent-indigo-light);
}

.card-badge.challenge {
  background: rgba(16, 185, 129, 0.2);
  color: var(--accent-emerald-light);
}

.theme-tag {
  font-size: 0.72rem;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.05);
  padding: 0.2rem 0.5rem;
  border-radius: 4px;
}

.card-content-text {
  color: var(--text-primary);
  font-size: 0.95rem;
  line-height: 1.6;
}

/* Connection Card */
.connection-card {
  background: var(--bg-card);
  border: 1px solid rgba(99, 102, 241, 0.3);
  border-radius: var(--radius-md);
  padding: 1.15rem 1.25rem;
  position: relative;
  overflow: hidden;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.25);
}

.connection-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-indigo) 0%, var(--accent-purple) 100%);
}

/* Challenge Card */
.challenge-card {
  background: linear-gradient(135deg, rgba(16, 185, 129, 0.1) 0%, rgba(6, 182, 212, 0.08) 100%);
  border: 1px solid rgba(16, 185, 129, 0.4);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  box-shadow: var(--shadow-glow-emerald);
  position: relative;
}

.challenge-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--accent-emerald) 0%, var(--accent-cyan) 100%);
}

.challenge-question {
  font-size: 1rem;
  font-weight: 600;
  color: #FFF;
  margin-top: 0.4rem;
  line-height: 1.5;
}

/* Interactive Action Toolbar for Tutor Response */
.tutor-action-bar {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin-top: 0.4rem;
}

.action-tool-btn {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  color: var(--text-secondary);
  font-size: 0.78rem;
  font-weight: 500;
  padding: 0.35rem 0.75rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.35rem;
  transition: all var(--transition-fast);
}

.action-tool-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  color: var(--text-primary);
  transform: translateY(-1px);
}

/* Typing / Thinking Indicator */
.typing-indicator {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  padding: 0.85rem 1.25rem;
  border-radius: 18px 18px 18px 4px;
  width: fit-content;
}

.typing-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-cyan);
  animation: typing-bounce 1.4s infinite ease-in-out both;
}

.typing-dot:nth-child(1) { animation-delay: -0.32s; }
.typing-dot:nth-child(2) { animation-delay: -0.16s; }

@keyframes typing-bounce {
  0%, 80%, 100% { transform: scale(0); opacity: 0.4; }
  40% { transform: scale(1); opacity: 1; }
}

/* ==========================================================================
   Chat Input Area & Action Chips
   ========================================================================== */
.chat-input-bar {
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-top: 1px solid var(--border-subtle);
  padding: 1rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  max-width: 960px;
  width: 100%;
  margin: 0 auto;
}

.action-chips-container {
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
  padding-bottom: 0.2rem;
}

.action-chips-container::-webkit-scrollbar {
  height: 4px;
}

.chip-btn {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 500;
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-pill);
  cursor: pointer;
  white-space: nowrap;
  transition: all var(--transition-fast);
}

.chip-btn:hover {
  background: rgba(99, 102, 241, 0.2);
  border-color: var(--accent-indigo);
  color: #FFF;
}

.input-form {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.input-wrapper {
  display: flex;
  align-items: flex-end;
  background: var(--bg-secondary);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-md);
  padding: 0.65rem 0.85rem;
  transition: all var(--transition-fast);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

.input-wrapper:focus-within {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 16px rgba(6, 182, 212, 0.3);
}

.chat-textarea {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  line-height: 1.5;
  resize: none;
  max-height: 140px;
  outline: none;
  padding: 0.3rem 0;
}

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

.input-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: 0.75rem;
}

.icon-control-btn {
  background: transparent;
  border: none;
  font-size: 1.2rem;
  cursor: pointer;
  padding: 0.4rem;
  border-radius: 8px;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

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

.icon-control-btn.recording {
  color: var(--accent-rose);
  animation: pulse-dot 1s infinite;
}

.send-btn {
  background: linear-gradient(135deg, var(--accent-indigo) 0%, var(--accent-cyan) 100%);
  border: none;
  color: #FFF;
  font-family: var(--font-heading);
  font-size: 0.9rem;
  font-weight: 700;
  padding: 0.6rem 1.15rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.45rem;
  transition: all var(--transition-fast);
  box-shadow: 0 2px 10px rgba(99, 102, 241, 0.35);
}

.send-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(6, 182, 212, 0.45);
}

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

.input-footnote {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-align: center;
}

.input-footnote kbd {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  padding: 0.1rem 0.35rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
}

/* ==========================================================================
   Buttons & Utility Classes
   ========================================================================== */
.btn-primary {
  background: linear-gradient(135deg, var(--accent-indigo) 0%, var(--accent-cyan) 100%);
  color: #FFF;
  border: none;
  border-radius: var(--radius-sm);
  padding: 0.6rem 1.25rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-primary:hover {
  opacity: 0.95;
  box-shadow: 0 2px 10px rgba(99, 102, 241, 0.3);
}

.btn-secondary {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.6rem 1.25rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

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

.btn-subtle {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  padding: 0.35rem 0.85rem;
  font-size: 0.82rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

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

.btn-block {
  width: 100%;
}

.icon-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 1.1rem;
  padding: 0.4rem;
  border-radius: 6px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
}

.icon-btn:hover {
  background: var(--bg-tertiary);
  color: #FFF;
}

.mobile-only {
  display: none;
}

/* ==========================================================================
   Modal Dialog
   ========================================================================== */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(5, 8, 15, 0.75);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 1.5rem;
  animation: fade-in 0.2s ease;
}

.modal-backdrop[hidden] {
  display: none;
}

.modal-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  max-width: 540px;
  width: 100%;
  box-shadow: var(--shadow-md), var(--shadow-glow);
  overflow: hidden;
}

.modal-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-family: var(--font-heading);
  font-size: 1.15rem;
  font-weight: 700;
  color: #FFF;
}

.modal-body {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
  max-height: 70vh;
  overflow-y: auto;
}

.modal-section h4 {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 0.65rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.mode-options {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.mode-radio-label {
  display: flex;
  align-items: flex-start;
  gap: 0.75rem;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.85rem 1rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.mode-radio-label:hover {
  border-color: var(--border-glow);
}

.mode-radio-label input {
  margin-top: 0.25rem;
}

.radio-title {
  display: block;
  font-weight: 600;
  color: var(--text-primary);
  font-size: 0.9rem;
}

.radio-desc {
  display: block;
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 0.2rem;
}

.field-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 0.4rem;
}

.field-hint {
  display: block;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.35rem;
}

.field-hint a {
  color: var(--accent-cyan);
  text-decoration: none;
}

.field-hint a:hover {
  text-decoration: underline;
}

.modal-footer {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  background: rgba(11, 15, 25, 0.4);
}

/* ==========================================================================
   Confetti Canvas
   ========================================================================== */
.confetti-canvas {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 999;
}

/* ==========================================================================
   Animations & Responsive
   ========================================================================== */
@keyframes fade-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes fade-in-up {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

@media (max-width: 900px) {
  .sidebar {
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    z-index: 50;
    transform: translateX(-100%);
    box-shadow: var(--shadow-md);
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .mobile-only {
    display: flex;
  }

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

  .welcome-hero-card {
    flex-direction: column;
    padding: 1.5rem;
  }
}

@media (min-width: 901px) {
  .mobile-menu-btn {
    display: none;
  }
}

/* ==========================================================================
   Analogy Trainer Studio Styles
   ========================================================================== */

/* Navbar Train Button */
.btn-train-nav {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, #7C3AED 0%, #4F46E5 50%, #06B6D4 100%);
  color: #FFF;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-pill);
  padding: 0.45rem 1rem;
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 0 16px rgba(124, 58, 237, 0.45);
  transition: all var(--transition-fast);
}

.btn-train-nav:hover {
  transform: translateY(-1px) scale(1.03);
  box-shadow: 0 0 24px rgba(6, 182, 212, 0.6);
}

/* Sidebar Train Studio Card */
.btn-train-studio {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 0.85rem;
  background: linear-gradient(135deg, rgba(124, 58, 237, 0.25) 0%, rgba(6, 182, 212, 0.15) 100%);
  border: 1px solid rgba(124, 58, 237, 0.45);
  border-radius: var(--radius-md);
  padding: 0.85rem 1rem;
  color: #FFF;
  cursor: pointer;
  text-align: left;
  transition: all var(--transition-fast);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.25);
}

.btn-train-studio:hover {
  background: linear-gradient(135deg, rgba(124, 58, 237, 0.4) 0%, rgba(6, 182, 212, 0.25) 100%);
  border-color: var(--accent-cyan);
  box-shadow: 0 0 20px rgba(124, 58, 237, 0.35);
  transform: translateY(-1px);
}

.btn-train-icon {
  font-size: 1.6rem;
  flex-shrink: 0;
}

.btn-train-text strong {
  display: block;
  font-family: var(--font-heading);
  font-size: 0.95rem;
  font-weight: 700;
  color: #FFF;
}

.btn-train-text small {
  display: block;
  font-size: 0.75rem;
  color: var(--accent-cyan-light);
}

/* Trainer Modal */
.trainer-modal-card {
  max-width: 820px;
  width: 95%;
}

.trainer-header-group {
  display: flex;
  align-items: center;
  gap: 0.85rem;
}

.trainer-badge-icon {
  font-size: 1.85rem;
}

.modal-subtitle {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 0.15rem;
}

/* Tabs Navigation */
.trainer-tabs-nav {
  display: flex;
  border-bottom: 1px solid var(--border-subtle);
  background: rgba(11, 15, 25, 0.5);
  padding: 0 1.5rem;
  gap: 0.5rem;
}

.trainer-tab {
  background: transparent;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-secondary);
  font-family: var(--font-heading);
  font-size: 0.88rem;
  font-weight: 600;
  padding: 0.85rem 1rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.trainer-tab:hover {
  color: var(--text-primary);
}

.trainer-tab.active {
  color: var(--accent-cyan-light);
  border-bottom-color: var(--accent-cyan);
}

.trainer-modal-body {
  max-height: 72vh;
  overflow-y: auto;
  padding: 1.5rem;
}

.trainer-tab-content {
  display: none;
}

.trainer-tab-content.active {
  display: flex;
  flex-direction: column;
  gap: 1.15rem;
  animation: fade-in 0.2s ease;
}

/* Form Layout */
.form-row-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.styled-textarea {
  resize: vertical;
  line-height: 1.5;
  font-family: var(--font-body);
}

.trainer-form-actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 0.5rem;
}

/* Library View */
.library-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.library-count-text {
  font-size: 0.82rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.concepts-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.85rem;
  max-height: 52vh;
  overflow-y: auto;
  padding-right: 0.25rem;
}

.concept-item-card {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  transition: all var(--transition-fast);
}

.concept-item-card:hover {
  border-color: var(--border-glow);
  background: var(--bg-card-hover);
}

.concept-card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.concept-card-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: #FFF;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.concept-realm-badge {
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  border-radius: var(--radius-pill);
  background: rgba(99, 102, 241, 0.2);
  color: var(--accent-indigo-light);
  border: 1px solid rgba(99, 102, 241, 0.3);
}

.concept-card-preview {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.concept-card-preview strong {
  color: var(--text-primary);
}

.concept-card-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 0.5rem;
  margin-top: 0.35rem;
  padding-top: 0.65rem;
  border-top: 1px solid var(--border-subtle);
}

.btn-concept-action {
  background: transparent;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 0.3rem 0.7rem;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-concept-action:hover {
  background: var(--bg-secondary);
  color: #FFF;
  border-color: var(--border-glow);
}

.btn-concept-action.test-btn {
  background: rgba(6, 182, 212, 0.15);
  border-color: rgba(6, 182, 212, 0.4);
  color: var(--accent-cyan-light);
}

.btn-concept-action.test-btn:hover {
  background: var(--accent-cyan);
  color: #000;
}

.btn-concept-action.delete-btn {
  color: var(--accent-rose);
}

.btn-concept-action.delete-btn:hover {
  background: rgba(244, 63, 94, 0.2);
  border-color: var(--accent-rose);
}

/* Bulk Import / Export */
.import-section h4, .export-section h4 {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: #FFF;
  margin-bottom: 0.35rem;
}

.import-btn-row {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 0.75rem;
}

/* ==========================================================================
   Owner Authentication Lock Styles
   ========================================================================== */

.auth-modal-card {
  max-width: 440px;
  width: 90%;
  border-color: rgba(245, 158, 11, 0.4);
  box-shadow: 0 0 24px rgba(245, 158, 11, 0.25);
}

.auth-modal-body {
  padding: 1.5rem;
}

.password-input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.password-input-wrapper input {
  padding-right: 2.8rem;
  letter-spacing: 0.05em;
}

.btn-toggle-eye {
  position: absolute;
  right: 0.75rem;
  background: transparent;
  border: none;
  cursor: pointer;
  font-size: 1.1rem;
  color: var(--text-muted);
  transition: color var(--transition-fast);
}

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

.auth-error-msg {
  color: var(--accent-rose);
  font-size: 0.82rem;
  font-weight: 600;
  margin-top: 0.45rem;
  animation: shake 0.35s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  75% { transform: translateX(6px); }
}

.owner-verified-tag {
  font-size: 0.72rem;
  font-weight: 700;
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.25) 0%, rgba(234, 88, 12, 0.25) 100%);
  color: var(--accent-amber-light);
  border: 1px solid rgba(245, 158, 11, 0.45);
  padding: 0.2rem 0.65rem;
  border-radius: var(--radius-pill);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  letter-spacing: 0.03em;
}