:root {
  --bg-primary: #0a0c10;
  --bg-secondary: #12161f;
  --bg-tertiary: #1a202c;
  --bg-glass: rgba(18, 22, 31, 0.75);
  --bg-glass-hover: rgba(26, 32, 44, 0.85);
  --border-color: rgba(255, 255, 255, 0.08);
  --border-focus: rgba(99, 102, 241, 0.5);
  
  --accent-primary: #6366f1;
  --accent-primary-hover: #4f46e5;
  --accent-glow: rgba(99, 102, 241, 0.35);
  --accent-secondary: #06b6d4;
  
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --text-dim: #6b7280;
  
  --danger: #ef4444;
  --danger-hover: #dc2626;
  --success: #10b981;
  
  --sidebar-width: 260px;
  --notes-list-width: 320px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --shadow-main: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
}

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

body {
  font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-main);
  height: 100vh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

/* Background Glowing Elements */
.glow-bg {
  position: absolute;
  width: 400px;
  height: 400px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--accent-glow) 0%, rgba(0,0,0,0) 70%);
  top: -100px;
  left: -100px;
  pointer-events: none;
  z-index: 0;
}

.glow-bg-secondary {
  position: absolute;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.15) 0%, rgba(0,0,0,0) 70%);
  bottom: -150px;
  right: -150px;
  pointer-events: none;
  z-index: 0;
}

/* App Header */
.header {
  height: 60px;
  background: var(--bg-glass);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  z-index: 10;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.25rem;
  color: #fff;
  letter-spacing: -0.5px;
}

.brand-icon {
  width: 32px;
  height: 32px;
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 15px var(--accent-glow);
}

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

.btn {
  background: var(--bg-tertiary);
  color: var(--text-main);
  border: 1px solid var(--border-color);
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  transition: all 0.2s ease;
}

.btn:hover {
  background: var(--bg-glass-hover);
  border-color: rgba(255, 255, 255, 0.2);
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-primary-hover));
  color: white;
  border: none;
  box-shadow: 0 4px 14px var(--accent-glow);
}

.btn-primary:hover {
  opacity: 0.95;
  transform: translateY(-1px);
}

.btn-danger {
  background: rgba(239, 68, 68, 0.15);
  color: var(--danger);
  border-color: rgba(239, 68, 68, 0.3);
}

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

.user-badge {
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--bg-tertiary);
  padding: 4px 12px 4px 4px;
  border-radius: 30px;
  border: 1px solid var(--border-color);
}

.user-avatar {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
}

/* Layout Container */
.main-container {
  display: flex;
  flex: 1;
  overflow: hidden;
  z-index: 1;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background: var(--bg-glass);
  backdrop-filter: blur(16px);
  border-right: 1px solid var(--border-color);
  padding: 20px 16px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.nav-section {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  color: var(--text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.15s ease;
}

.nav-item:hover, .nav-item.active {
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-main);
}

.nav-item.active {
  border-left: 3px solid var(--accent-primary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

/* Notes List Panel */
.notes-panel {
  width: var(--notes-list-width);
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
}

.notes-header {
  padding: 16px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.search-bar {
  position: relative;
}

.search-input {
  width: 100%;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 8px 12px 8px 36px;
  color: var(--text-main);
  font-size: 0.875rem;
  outline: none;
  transition: border-color 0.2s;
}

.search-input:focus {
  border-color: var(--accent-primary);
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-dim);
}

.notes-list {
  flex: 1;
  overflow-y: auto;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.note-card {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 14px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.note-card:hover {
  background: var(--bg-glass-hover);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-1px);
}

.note-card.active {
  border-color: var(--accent-primary);
  background: rgba(99, 102, 241, 0.1);
}

.note-card-title {
  font-weight: 600;
  font-size: 0.95rem;
  color: var(--text-main);
  margin-bottom: 6px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.note-card-snippet {
  font-size: 0.8rem;
  color: var(--text-muted);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  line-height: 1.4;
}

.note-card-date {
  font-size: 0.7rem;
  color: var(--text-dim);
  margin-top: 8px;
}

/* Editor Panel */
.editor-panel {
  flex: 1;
  background: var(--bg-primary);
  display: flex;
  flex-direction: column;
}

.editor-toolbar {
  height: 56px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  background: var(--bg-secondary);
}

.editor-status {
  font-size: 0.8rem;
  color: var(--text-dim);
  display: flex;
  align-items: center;
  gap: 6px;
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--success);
}

.editor-body {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 32px 48px;
  overflow-y: auto;
}

.editor-title {
  background: transparent;
  border: none;
  color: var(--text-main);
  font-size: 2.2rem;
  font-weight: 800;
  outline: none;
  margin-bottom: 20px;
  width: 100%;
}

.editor-title::placeholder {
  color: var(--text-dim);
}

.editor-content {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-main);
  font-size: 1.1rem;
  line-height: 1.7;
  outline: none;
  resize: none;
  font-family: inherit;
}

.editor-content::placeholder {
  color: var(--text-dim);
}

.empty-state {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  color: var(--text-dim);
  gap: 16px;
  text-align: center;
}

/* Auth Modal */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.modal-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 400px;
  padding: 32px;
  box-shadow: var(--shadow-main);
  transform: translateY(20px);
  transition: transform 0.25s ease;
}

.modal-overlay.active .modal-card {
  transform: translateY(0);
}

.modal-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.modal-subtitle {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 16px;
}

.form-label {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
}

.form-input {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-sm);
  padding: 10px 14px;
  color: var(--text-main);
  font-size: 0.95rem;
  outline: none;
}

.form-input:focus {
  border-color: var(--accent-primary);
}

.form-toggle {
  margin-top: 16px;
  font-size: 0.85rem;
  color: var(--text-muted);
  text-align: center;
}

.form-toggle span {
  color: var(--accent-primary);
  cursor: pointer;
  font-weight: 600;
}

.toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-main);
  display: flex;
  align-items: center;
  gap: 10px;
  z-index: 200;
  transform: translateY(100px);
  transition: transform 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

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