:root {
  --bg-primary: #0f0f1a;
  --bg-secondary: #1a1a2e;
  --bg-card: rgba(255, 255, 255, 0.05);
  --bg-glass: rgba(255, 255, 255, 0.08);
  --bg-glass-hover: rgba(255, 255, 255, 0.12);
  --text-primary: #e8e8f0;
  --text-secondary: #9898b8;
  --text-muted: #6a6a8a;
  --accent: #6c5ce7;
  --accent-glow: rgba(108, 92, 231, 0.3);
  --accent-secondary: #00d2ff;
  --danger: #ff4757;
  --danger-glow: rgba(255, 71, 87, 0.3);
  --success: #2ed573;
  --border: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.15);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --gradient-primary: linear-gradient(135deg, #6c5ce7, #a29bfe);
  --gradient-accent: linear-gradient(135deg, #6c5ce7, #00d2ff);
  --gradient-hero: linear-gradient(135deg, #0f0f1a 0%, #1a1a2e 50%, #16213e 100%);
  --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --radius: 16px;
  --radius-sm: 10px;
  --radius-xs: 6px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 720px;
}

[data-theme="light"] {
  --bg-primary: #f5f5fa;
  --bg-secondary: #ffffff;
  --bg-card: rgba(0, 0, 0, 0.03);
  --bg-glass: rgba(255, 255, 255, 0.7);
  --bg-glass-hover: rgba(255, 255, 255, 0.85);
  --text-primary: #1a1a2e;
  --text-secondary: #5a5a7a;
  --text-muted: #8a8aaa;
  --border: rgba(0, 0, 0, 0.08);
  --border-hover: rgba(0, 0, 0, 0.15);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  --gradient-hero: linear-gradient(135deg, #f5f5fa 0%, #e8e8f5 50%, #ddddf5 100%);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font);
  background: var(--bg-primary);
  color: var(--text-primary);
  min-height: 100vh;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  transition: background var(--transition), color var(--transition);
}

#app {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
  padding-top: 80px;
}

.glass {
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  transition: all var(--transition);
}

.glass:hover {
  border-color: var(--border-hover);
  background: var(--bg-glass-hover);
}

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(20px);
  transition: background var(--transition);
}

.header-content {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.logo span {
  font-weight: 300;
  opacity: 0.8;
}

.tagline {
  font-size: 0.75rem;
  color: var(--text-muted);
  display: none;
}

.header-nav {
  display: flex;
  gap: 6px;
}

.nav-btn {
  background: var(--bg-glass);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 8px 14px;
  border-radius: var(--radius-xs);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.nav-btn:hover {
  background: var(--bg-glass-hover);
  color: var(--text-primary);
  border-color: var(--accent);
}

.nav-btn.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
  box-shadow: var(--accent-glow);
}

.hero {
  position: relative;
  text-align: center;
  padding: 60px 20px 40px;
  margin-bottom: 30px;
  overflow: hidden;
  border-radius: var(--radius);
  background: var(--gradient-hero);
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 50%, var(--accent-glow) 0%, transparent 50%),
    radial-gradient(circle at 80% 50%, rgba(0, 210, 255, 0.15) 0%, transparent 50%);
  opacity: 0.5;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-content h2 {
  font-size: 2rem;
  font-weight: 800;
  margin-bottom: 8px;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-content p {
  color: var(--text-secondary);
  font-size: 1.05rem;
}

.submit-section {
  margin-bottom: 30px;
}

.submit-card {
  padding: 24px;
}

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

.card-header h3 {
  font-size: 1.1rem;
  font-weight: 600;
}

.char-count {
  font-size: 0.8rem;
  color: var(--text-muted);
  font-weight: 500;
}

.char-count.warning {
  color: #ffa502;
}

.char-count.danger {
  color: var(--danger);
}

textarea {
  width: 100%;
  padding: 16px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font);
  font-size: 1rem;
  line-height: 1.6;
  resize: vertical;
  min-height: 120px;
  transition: border var(--transition);
  outline: none;
}

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

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

.form-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 12px;
}

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

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  background: var(--gradient-primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
  position: relative;
  overflow: hidden;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--accent-glow);
}

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

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

.btn-primary .btn-loader {
  width: 18px;
  height: 18px;
  border: 2px solid rgba(255,255,255,0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.feed-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 20px;
}

.feed-header h2 {
  font-size: 1.3rem;
  font-weight: 700;
}

.filter-chips {
  display: flex;
  gap: 6px;
}

.chip {
  padding: 6px 14px;
  background: var(--bg-glass);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.chip:hover {
  background: var(--bg-glass-hover);
  color: var(--text-primary);
}

.chip.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.feed {
  display: flex;
  flex-direction: column;
  gap: 16px;
  min-height: 200px;
}

.confession-card {
  padding: 24px;
  animation: fadeInUp 0.4s ease-out;
  position: relative;
  overflow: hidden;
}

.confession-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-accent);
  border-radius: 0 2px 2px 0;
  opacity: 0;
  transition: opacity var(--transition);
}

.confession-card:hover::before {
  opacity: 1;
}

.confession-text {
  font-size: 1rem;
  line-height: 1.7;
  margin-bottom: 16px;
  word-wrap: break-word;
}

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

.confession-time {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.confession-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.reaction-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 6px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 20px;
  color: var(--text-secondary);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.reaction-btn:hover {
  background: var(--bg-glass-hover);
  border-color: var(--accent);
  transform: translateY(-2px);
}

.reaction-btn:active {
  transform: scale(0.9);
}

.reaction-btn .emoji {
  font-size: 1.1rem;
  line-height: 1;
}

.reaction-btn .count {
  font-weight: 600;
  min-width: 12px;
}

.reaction-btn.pop {
  animation: pop 0.3s ease-out;
}

@keyframes pop {
  0% { transform: scale(1); }
  50% { transform: scale(1.3); }
  100% { transform: scale(1); }
}

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

.report-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.75rem;
  cursor: pointer;
  transition: color var(--transition);
  font-family: var(--font);
}

.report-btn:hover {
  color: var(--danger);
}

.ai-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px 10px;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-xs);
  color: var(--text-muted);
  font-size: 0.75rem;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

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

.ai-btn.loading {
  opacity: 0.7;
  cursor: default;
}

.ai-btn .ai-btn-loader {
  width: 12px;
  height: 12px;
  border: 2px solid var(--accent);
  border-top-color: transparent;
  border-radius: 50%;
  animation: spin 0.6s linear infinite;
}

.ai-analysis {
  margin-top: 16px;
  padding: 16px;
  background: var(--bg-card);
  border: 1px solid var(--accent);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent);
  animation: fadeInUp 0.3s ease-out;
}

.ai-analysis-content {
  font-size: 0.9rem;
  line-height: 1.7;
  color: var(--text-primary);
  white-space: pre-wrap;
}

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

.loading-skeleton {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.skeleton-card {
  padding: 24px;
  background: var(--bg-glass);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  height: 140px;
  position: relative;
  overflow: hidden;
}

.skeleton-card::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.05),
    transparent
  );
  animation: shimmer 1.5s infinite;
}

@keyframes shimmer {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

.empty-state {
  text-align: center;
  padding: 60px 20px;
}

.empty-icon {
  font-size: 3rem;
  margin-bottom: 16px;
}

.empty-state h3 {
  font-size: 1.2rem;
  margin-bottom: 8px;
}

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

.infinite-scroll-sentinel {
  height: 1px;
  width: 100%;
}

.feed-footer {
  padding: 20px 0;
  text-align: center;
}

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

.theme-toggle {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 99;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--gradient-accent);
  border: none;
  color: #fff;
  font-size: 1.3rem;
  cursor: pointer;
  transition: all var(--transition);
  box-shadow: 0 4px 15px var(--accent-glow);
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 25px var(--accent-glow);
}

.theme-toggle:active {
  transform: scale(0.95);
}

.toast-container {
  position: fixed;
  top: 80px;
  right: 20px;
  z-index: 1000;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  padding: 12px 20px;
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.9rem;
  font-weight: 500;
  animation: slideIn 0.3s ease-out;
  pointer-events: auto;
  max-width: 360px;
  box-shadow: var(--shadow);
}

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

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

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

.toast.removing {
  animation: slideOut 0.3s ease-in forwards;
}

@keyframes slideOut {
  to {
    opacity: 0;
    transform: translateX(100px);
  }
}

.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  z-index: 200;
  display: none;
  align-items: center;
  justify-content: center;
}

.modal-overlay.open {
  display: flex;
  animation: fadeIn 0.2s ease-out;
}

.modal {
  padding: 32px;
  max-width: 420px;
  width: 90%;
  text-align: center;
}

.modal h3 {
  font-size: 1.2rem;
  margin-bottom: 12px;
}

.modal p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 24px;
  line-height: 1.5;
}

.modal-actions {
  display: flex;
  gap: 10px;
  justify-content: center;
}

.btn-secondary {
  padding: 10px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.btn-secondary:hover {
  background: var(--bg-glass-hover);
}

.btn-danger {
  padding: 10px 24px;
  background: var(--danger);
  border: none;
  border-radius: var(--radius-sm);
  color: #fff;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  font-family: var(--font);
}

.btn-danger:hover {
  box-shadow: 0 4px 15px var(--danger-glow);
  transform: translateY(-2px);
}

.skip-link {
  position: fixed;
  top: -100%;
  left: 50%;
  transform: translateX(-50%);
  z-index: 9999;
  padding: 10px 20px;
  background: var(--accent);
  color: #fff;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  font-weight: 600;
  text-decoration: none;
  font-family: var(--font);
  font-size: 0.9rem;
}

.skip-link:focus {
  top: 0;
}

.footer {
  text-align: center;
  padding: 40px 20px;
  color: var(--text-muted);
  font-size: 0.8rem;
}

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

@media (min-width: 640px) {
  .tagline {
    display: block;
  }

  .hero-content h2 {
    font-size: 2.5rem;
  }

  .confession-card {
    padding: 28px;
  }
}

@media (max-width: 480px) {
  #app {
    padding-top: 64px;
    padding-left: 12px;
    padding-right: 12px;
  }

  .header-content {
    padding: 10px 12px;
  }

  .logo {
    font-size: 1.2rem;
  }

  .nav-btn {
    padding: 6px 10px;
    font-size: 0.72rem;
  }

  .hero {
    padding: 40px 16px 30px;
  }

  .hero-content h2 {
    font-size: 1.6rem;
  }

  .hero-content p {
    font-size: 0.9rem;
  }

  .submit-card {
    padding: 16px;
  }

  .confession-card {
    padding: 16px;
  }

  .reaction-btn {
    padding: 4px 10px;
    font-size: 0.8rem;
  }
}