:root {
  /* Premium Dark Theme Palette */
  --bg-dark: #09090b;
  --bg-ambient-1: rgba(99, 102, 241, 0.15);
  --bg-ambient-2: rgba(168, 85, 247, 0.15);
  
  --surface-base: rgba(24, 24, 27, 0.6);
  --surface-hover: rgba(39, 39, 42, 0.8);
  --surface-border: rgba(255, 255, 255, 0.08);
  --surface-border-hover: rgba(255, 255, 255, 0.15);
  --surface-input-bg: rgba(0, 0, 0, 0.3);
  
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  
  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --accent-glow: rgba(99, 102, 241, 0.4);
  
  --success: #10b981;
  --success-glow: rgba(16, 185, 129, 0.2);
  --error: #ef4444;
  --error-bg: rgba(239, 68, 68, 0.1);
  --gradient-text: linear-gradient(135deg, #fff 0%, #a5b4fc 100%);
  
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-full: 9999px;
  
  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

html[data-theme="light"] {
  --bg-dark: #f8fafc;
  --bg-ambient-1: rgba(99, 102, 241, 0.1);
  --bg-ambient-2: rgba(168, 85, 247, 0.1);
  
  --surface-base: rgba(255, 255, 255, 0.7);
  --surface-hover: rgba(241, 245, 249, 0.8);
  --surface-border: rgba(0, 0, 0, 0.08);
  --surface-border-hover: rgba(0, 0, 0, 0.15);
  --surface-input-bg: rgba(255, 255, 255, 0.8);
  
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  
  --accent: #4f46e5;
  --accent-hover: #4338ca;
  --accent-glow: rgba(79, 70, 229, 0.25);
  
  --gradient-text: linear-gradient(135deg, #0f172a 0%, #4f46e5 100%);
}

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

body {
  font-family: 'Plus Jakarta Sans', system-ui, sans-serif;
  background-color: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.5;
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

/* Ambient Background Orbs */
.ambient-background {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

.glow-orb {
  position: absolute;
  width: 600px;
  height: 600px;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.6;
}

.orb-1 {
  background: var(--bg-ambient-1);
  top: -100px;
  left: -200px;
  animation: float 20s ease-in-out infinite alternate;
}

.orb-2 {
  background: var(--bg-ambient-2);
  bottom: -200px;
  right: -100px;
  animation: float 25s ease-in-out infinite alternate-reverse;
}

@keyframes float {
  0% { transform: translate(0, 0) scale(1); }
  50% { transform: translate(100px, 50px) scale(1.1); }
  100% { transform: translate(-50px, 100px) scale(0.9); }
}

/* App Layout */
.app-container {
  max-width: 640px;
  margin: 0 auto;
  padding: 4rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 3rem;
}

.app-header {
  text-align: center;
  animation: fadeSlideDown 0.8s var(--transition-smooth);
}

.header-top-row {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  margin-bottom: 0.75rem;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 1rem;
}

.logo-icon {
  width: 48px;
  height: 48px;
  color: var(--accent);
}

.main-title {
  font-size: 4.5rem;
  font-weight: 900;
  letter-spacing: -0.06em;
  background: var(--gradient-text);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin: 0;
  line-height: 1;
  filter: drop-shadow(0 4px 16px var(--accent-glow));
}

.theme-toggle {
  position: absolute;
  right: 0;
  background: rgba(0, 0, 0, 0.1);
  border: 1px solid var(--surface-border);
  color: var(--text-secondary);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition-fast);
}

html[data-theme="light"] .theme-toggle {
  background: rgba(255, 255, 255, 0.5);
}

.theme-toggle:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--surface-base);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  position: absolute;
  transition: transform 0.4s ease, opacity 0.4s ease;
}

html[data-theme="dark"] .sun-icon {
  opacity: 0;
  transform: rotate(-90deg) scale(0.5);
}

html[data-theme="light"] .moon-icon {
  opacity: 0;
  transform: rotate(90deg) scale(0.5);
}

.subtitle {
  color: var(--text-secondary);
  font-size: 1.125rem;
  font-weight: 500;
}

/* Glassmorphic Panel */
.glass-panel {
  background: var(--surface-base);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-lg);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
}

.main-card {
  padding: 0.5rem;
  animation: fadeSlideUp 0.8s var(--transition-smooth) 0.1s both;
  overflow: hidden;
  transition: height var(--transition-smooth);
}

.form-container {
  padding: 1.5rem;
}

/* Inputs & Buttons */
.input-wrapper {
  position: relative;
  display: flex;
  align-items: center;
  background: var(--surface-input-bg);
  border: 1px solid var(--surface-border);
  transition: var(--transition-fast);
}

.input-wrapper:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px var(--accent), 0 0 15px var(--accent-glow);
}

.main-input {
  border-radius: var(--radius-md);
  padding: 0.5rem;
  gap: 0.5rem;
}

.input-icon {
  width: 20px;
  height: 20px;
  color: var(--text-muted);
  margin-left: 1rem;
}

.input-wrapper input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-primary);
  font-family: inherit;
  font-size: 1.05rem;
  padding: 0.75rem 0.5rem;
}

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

.primary-btn {
  background: var(--accent);
  color: white;
  border: none;
  padding: 0.875rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  font-family: inherit;
  font-size: 0.95rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  transition: var(--transition-fast);
  box-shadow: 0 4px 12px var(--accent-glow);
}

.primary-btn svg {
  width: 18px;
  height: 18px;
  transition: transform var(--transition-fast);
}

.primary-btn:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
}

.primary-btn:hover svg {
  transform: translateX(3px);
}

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

/* Advanced Options */
.options-trigger {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1.5rem;
  color: var(--text-secondary);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition-fast);
  user-select: none;
}

.options-trigger:hover {
  color: var(--text-primary);
}

.chevron {
  width: 16px;
  height: 16px;
  transition: transform var(--transition-smooth);
}

.options-trigger.active .chevron {
  transform: rotate(180deg);
}

.advanced-options-panel {
  max-height: 0;
  overflow: hidden;
  opacity: 0;
  transition: all var(--transition-smooth);
}

.advanced-options-panel.open {
  max-height: 300px;
  opacity: 1;
  margin-top: 1.5rem;
}

.options-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  padding-top: 0.5rem;
}

.form-group label {
  display: block;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.slim-input {
  border-radius: var(--radius-sm);
  height: 44px;
}

.slim-input input {
  font-size: 0.9rem;
  padding: 0.5rem 1rem;
}

.slim-input .prefix {
  color: var(--text-muted);
  padding-left: 1rem;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.85rem;
}

.slim-input input.date-picker {
  color-scheme: dark;
}

/* State Layers (Loading, Success, Error) */
.state-layer {
  position: relative;
}

.state-content {
  padding: 0 1.5rem 1.5rem;
  animation: fadeIn 0.4s var(--transition-smooth);
}

.hidden {
  display: none !important;
}

/* Loading */
#loading {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
  padding: 3rem 0;
  color: var(--text-secondary);
  font-weight: 500;
}

.nexus-spinner {
  width: 32px;
  height: 32px;
  border: 3px solid rgba(255,255,255,0.1);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 1s cubic-bezier(0.6, 0.2, 0.4, 0.8) infinite;
}

/* Success Result */
.result-header {
  margin-bottom: 1.5rem;
  padding-top: 1rem;
  border-top: 1px solid var(--surface-border);
}

.success-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: var(--success-glow);
  color: var(--success);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.success-badge svg {
  width: 14px;
  height: 14px;
}

.result-layout {
  display: flex;
  gap: 1.5rem;
  align-items: stretch;
}

.qr-container {
  background: white;
  padding: 0.5rem;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 20px rgba(0,0,0,0.5);
}

#qr-code-canvas {
  width: 120px !important;
  height: 120px !important;
  display: block;
}

.result-details {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1rem;
  min-width: 0;
}

.short-link-display {
  background: var(--surface-input-bg);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-sm);
  padding: 1rem;
  overflow: hidden;
}

.short-link-display a {
  color: var(--accent);
  font-family: 'JetBrains Mono', monospace;
  font-size: 1.1rem;
  font-weight: 500;
  text-decoration: none;
  display: block;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  transition: var(--transition-fast);
}

.short-link-display a:hover {
  text-shadow: 0 0 10px var(--accent-glow);
}

.action-row {
  display: flex;
  gap: 0.75rem;
}

.secondary-btn {
  background: var(--surface-hover);
  border: 1px solid var(--surface-border);
  color: var(--text-primary);
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: var(--transition-fast);
}

.flex-btn {
  flex: 1;
}

.secondary-btn svg {
  width: 16px;
  height: 16px;
  color: var(--text-secondary);
}

.secondary-btn:hover {
  background: rgba(255,255,255,0.1);
  border-color: var(--surface-border-hover);
}

.secondary-btn.copied {
  background: var(--success);
  border-color: var(--success);
  color: white;
}

.secondary-btn.copied svg {
  color: white;
}

/* Error State */
.error-view {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 1.5rem;
  background: var(--error-bg);
  border-radius: var(--radius-md);
  color: var(--error);
  font-weight: 500;
  margin-top: 1rem;
}

.error-icon {
  width: 24px;
  height: 24px;
  flex-shrink: 0;
}

/* Recent Links */
.recent-links-section {
  animation: fadeSlideUp 0.8s var(--transition-smooth) 0.2s both;
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 1.5rem;
}

.section-header h2 {
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.text-link {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.875rem;
  font-family: inherit;
  cursor: pointer;
  transition: var(--transition-fast);
}

.text-link:hover {
  color: var(--error);
}

.links-list {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.history-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.25rem;
  background: var(--surface-base);
  border: 1px solid var(--surface-border);
  border-radius: var(--radius-md);
  transition: var(--transition-fast);
}

.history-item:hover {
  background: var(--surface-hover);
  border-color: var(--surface-border-hover);
}

.history-details {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  overflow: hidden;
  padding-right: 1rem;
}

.history-short {
  color: var(--accent);
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.95rem;
  text-decoration: none;
}

.history-original {
  color: var(--text-secondary);
  font-size: 0.8rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.history-actions {
  display: flex;
  gap: 0.5rem;
}

.icon-btn {
  background: var(--surface-input-bg);
  border: 1px solid transparent;
  color: var(--text-secondary);
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition-fast);
}

.icon-btn svg {
  width: 16px;
  height: 16px;
}

.icon-btn:hover {
  background: var(--surface-hover);
  color: var(--text-primary);
  border-color: var(--surface-border);
}

/* Modal */
.nexus-modal {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
}

.modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,0.6);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: opacity 0.3s ease;
}

.modal-surface {
  position: relative;
  width: 100%;
  max-width: 440px;
  padding: 2.5rem;
  z-index: 101;
  transform: scale(1);
  opacity: 1;
  transition: all 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.nexus-modal.hidden .modal-backdrop {
  opacity: 0;
}

.nexus-modal.hidden .modal-surface {
  transform: scale(0.96) translateY(10px);
  opacity: 0;
}

.modal-close {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 50%;
  transition: var(--transition-fast);
}

.modal-close svg {
  width: 20px;
  height: 20px;
}

.modal-close:hover {
  background: rgba(255,255,255,0.1);
  color: white;
}

.modal-header {
  margin-bottom: 2rem;
}

.modal-header h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.mono-code {
  font-family: 'JetBrains Mono', monospace;
  color: var(--accent);
  font-size: 0.95rem;
}

.analytics-dashboard {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.metric-card {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  background: var(--surface-input-bg);
  border: 1px solid var(--surface-border);
  padding: 1.25rem;
  border-radius: var(--radius-md);
}

.metric-card.highlight {
  background: linear-gradient(145deg, var(--bg-ambient-1), var(--surface-input-bg));
  border-color: rgba(99, 102, 241, 0.3);
}

.metric-icon {
  width: 48px;
  height: 48px;
  background: var(--surface-border);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
}

.highlight .metric-icon {
  background: var(--accent-glow);
  color: var(--accent);
}

.metric-icon svg {
  width: 24px;
  height: 24px;
}

.metric-data {
  display: flex;
  flex-direction: column;
}

.metric-label {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  font-weight: 600;
}

.metric-value {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
}

.metric-value.date {
  font-size: 1.1rem;
  font-weight: 500;
  margin-top: 0.25rem;
}

/* Animations */
@keyframes fadeSlideUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

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

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

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

/* Responsive */
@media (max-width: 640px) {
  .app-container {
    padding: 2rem 1rem;
    gap: 2rem;
  }
  
  .main-input {
    flex-direction: column;
    align-items: stretch;
    padding: 0.5rem;
    background: transparent;
    border: none;
  }
  
  .main-input .input-icon {
    display: none;
  }
  
  .main-input input {
    background: var(--surface-input-bg);
    border: 1px solid var(--surface-border);
    border-radius: var(--radius-sm);
    padding: 1rem;
  }
  
  .primary-btn {
    padding: 1rem;
    justify-content: center;
  }
  
  .options-grid {
    grid-template-columns: 1fr;
  }
  
  .result-layout {
    flex-direction: column;
    align-items: center;
  }
  
  .qr-container {
    margin-bottom: 0.5rem;
  }
  
  .result-details {
    width: 100%;
  }
}