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

:root {
  --app-primary: #667eea;
  --app-secondary: #764ba2;
  --app-bg: #f0f2f5;
  --app-card: #ffffff;
  --app-text: #2d3436;
  --app-text-secondary: #636e72;
  --app-border: #e0e0e0;
  --app-radius: 10px;
  --app-shadow: 0 2px 8px rgba(0,0,0,0.08);
  --app-shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
  --app-danger: #e74c3c;
  --app-success: #00b894;
  --sidebar-width: 200px;
  --preview-width: 380px;
  --header-height: 56px;
  --level-tabs-height: 48px;
}

html, body {
  height: 100%;
  font-family: system-ui, -apple-system, sans-serif;
  background: var(--app-bg);
  color: var(--app-text);
  font-size: 15px;
  line-height: 1.5;
}

/* Header */
.app-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-height);
  background: linear-gradient(135deg, var(--app-primary), var(--app-secondary));
  color: #fff;
  display: flex;
  align-items: center;
  padding: 0 20px;
  gap: 16px;
  z-index: 100;
  box-shadow: 0 2px 12px rgba(102,126,234,0.3);
}
.app-header h1 { font-size: 1.1rem; font-weight: 700; white-space: nowrap; }
.header-spacer { flex: 1; }
.header-actions { display: flex; gap: 6px; align-items: center; }

/* Level tabs */
.level-tabs {
  position: fixed;
  top: var(--header-height);
  left: 0; right: 0;
  height: var(--level-tabs-height);
  background: var(--app-card);
  border-bottom: 1px solid var(--app-border);
  display: flex;
  z-index: 99;
  padding: 0 20px;
}

.level-tab {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 6px 24px;
  border: none;
  background: none;
  cursor: pointer;
  font-family: inherit;
  border-bottom: 3px solid transparent;
  transition: all 0.15s;
  color: var(--app-text-secondary);
  gap: 1px;
}
.level-tab strong { font-size: 0.85rem; font-weight: 600; }
.level-tab small { font-size: 0.7rem; opacity: 0.7; }
.level-tab:hover { color: var(--app-text); background: rgba(102,126,234,0.04); }
.level-tab.active {
  color: var(--app-primary);
  border-bottom-color: var(--app-primary);
}
.level-tab.active strong { color: var(--app-primary); }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border: none;
  border-radius: 6px;
  font-size: 0.83rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
  font-family: inherit;
}
.btn-primary { background: var(--app-primary); color: #fff; }
.btn-primary:hover { background: #5a71d4; }
.btn-secondary { background: rgba(255,255,255,0.15); color: #fff; border: 1px solid rgba(255,255,255,0.3); }
.btn-secondary:hover { background: rgba(255,255,255,0.25); }
.btn-ghost { background: transparent; color: var(--app-text-secondary); padding: 6px 10px; }
.btn-ghost:hover { background: rgba(0,0,0,0.05); }
.btn-danger { background: var(--app-danger); color: #fff; }
.btn-danger:hover { background: #c0392b; }
.btn-success { background: var(--app-success); color: #fff; }
.btn-success:hover { background: #00a884; }
.btn-sm { padding: 4px 10px; font-size: 0.8rem; }
.btn-icon {
  padding: 6px;
  background: transparent;
  border: none;
  cursor: pointer;
  border-radius: 4px;
  font-size: 1rem;
  transition: background 0.2s;
  color: var(--app-text-secondary);
}
.btn-icon:hover { background: rgba(0,0,0,0.06); }

/* Layout */
.app-layout {
  display: flex;
  margin-top: calc(var(--header-height) + var(--level-tabs-height));
  height: calc(100vh - var(--header-height) - var(--level-tabs-height));
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background: var(--app-card);
  border-right: 1px solid var(--app-border);
  overflow-y: auto;
  flex-shrink: 0;
  padding: 8px 0;
}

.sidebar-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 16px;
  cursor: pointer;
  font-size: 0.85rem;
  color: var(--app-text-secondary);
  transition: all 0.15s;
  border-left: 3px solid transparent;
}
.sidebar-item:hover { background: rgba(102,126,234,0.06); color: var(--app-text); }
.sidebar-item.active { background: rgba(102,126,234,0.1); color: var(--app-primary); border-left-color: var(--app-primary); font-weight: 600; }
.sidebar-icon { font-size: 1rem; width: 22px; text-align: center; }
.sidebar-count { margin-left: auto; background: var(--app-bg); color: var(--app-text-secondary); font-size: 0.72rem; padding: 1px 6px; border-radius: 10px; font-weight: 600; }

/* Main content */
.main-content { flex: 1; overflow-y: auto; padding: 20px; min-width: 0; }
.main-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.main-header h2 { font-size: 1.2rem; font-weight: 700; }

/* Token cards */
.token-list { display: flex; flex-direction: column; gap: 8px; }
.token-card {
  background: var(--app-card);
  border: 1px solid var(--app-border);
  border-radius: var(--app-radius);
  padding: 12px 16px;
  display: flex;
  align-items: center;
  gap: 12px;
  transition: box-shadow 0.2s, border-color 0.2s;
}
.token-card:hover { box-shadow: var(--app-shadow); border-color: rgba(102,126,234,0.3); }
.token-card-component { align-items: flex-start; }

.token-color-preview {
  width: 34px; height: 34px;
  border-radius: 8px;
  border: 2px solid var(--app-border);
  flex-shrink: 0;
}

.token-info { flex: 1; min-width: 0; }
.token-css-var { font-family: 'SF Mono', 'Fira Code', monospace; font-size: 0.85rem; font-weight: 600; color: var(--app-text); }
.token-name { font-size: 0.8rem; color: var(--app-text-secondary); margin-top: 1px; }
.token-value { font-family: 'SF Mono', 'Fira Code', monospace; font-size: 0.78rem; color: var(--app-text-secondary); margin-top: 2px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.token-actions { display: flex; gap: 4px; flex-shrink: 0; }

/* Component style preview */
.comp-style-preview {
  flex-shrink: 0;
  max-width: 260px;
  min-width: 160px;
}
.comp-style-line {
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 0.72rem;
  color: var(--app-text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  line-height: 1.6;
}

/* Component style editor (modal) */
.comp-styles-editor { display: flex; flex-direction: column; gap: 6px; }
.comp-style-row {
  display: flex;
  gap: 6px;
  align-items: center;
}
.comp-style-row input {
  flex: 1;
  padding: 7px 10px;
  border: 1px solid var(--app-border);
  border-radius: 6px;
  font-size: 0.83rem;
  font-family: 'SF Mono', 'Fira Code', monospace;
  background: #fff;
  color: var(--app-text);
}
.comp-style-row input:focus { outline: none; border-color: var(--app-primary); box-shadow: 0 0 0 3px rgba(102,126,234,0.15); }

/* Preview panel */
.preview-panel {
  width: var(--preview-width);
  background: var(--app-card);
  border-left: 1px solid var(--app-border);
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
.preview-header { padding: 12px 16px; border-bottom: 1px solid var(--app-border); font-weight: 600; font-size: 0.85rem; color: var(--app-text-secondary); }
.preview-frame { flex: 1; overflow-y: auto; padding: 16px; }

/* Modal */
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.4);
  display: flex; align-items: center; justify-content: center;
  z-index: 1000;
  animation: fadeIn 0.15s ease;
}
.modal {
  background: var(--app-card);
  border-radius: 12px;
  width: 90%; max-width: 500px;
  max-height: 85vh;
  overflow-y: auto;
  box-shadow: var(--app-shadow-lg);
  animation: slideUp 0.2s ease;
}
.modal-wide { max-width: 640px; }
.modal-header { padding: 16px 20px; border-bottom: 1px solid var(--app-border); display: flex; align-items: center; justify-content: space-between; }
.modal-header h3 { font-size: 1rem; font-weight: 700; }
.modal-body { padding: 20px; }
.modal-footer { padding: 14px 20px; border-top: 1px solid var(--app-border); display: flex; justify-content: flex-end; gap: 10px; }

/* Form */
.form-group { margin-bottom: 14px; }
.form-group label { display: block; font-size: 0.83rem; font-weight: 600; color: var(--app-text-secondary); margin-bottom: 5px; }
.form-group input, .form-group select, .form-group textarea {
  width: 100%; padding: 8px 12px;
  border: 1px solid var(--app-border); border-radius: 6px;
  font-size: 0.88rem; font-family: inherit;
  transition: border-color 0.2s;
  background: #fff; color: var(--app-text);
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
  outline: none; border-color: var(--app-primary);
  box-shadow: 0 0 0 3px rgba(102,126,234,0.15);
}
.form-group textarea { resize: vertical; min-height: 60px; }
.form-group input[type="color"] { height: 40px; padding: 4px; cursor: pointer; }
.css-var-preview { font-family: 'SF Mono', 'Fira Code', monospace; font-size: 0.78rem; color: var(--app-primary); margin-top: 4px; }
.form-error { color: var(--app-danger); font-size: 0.78rem; margin-top: 4px; }

/* Toast */
.toast-container { position: fixed; bottom: 20px; right: 20px; z-index: 2000; display: flex; flex-direction: column; gap: 8px; }
.toast { padding: 10px 18px; border-radius: 8px; color: #fff; font-size: 0.88rem; font-weight: 500; box-shadow: var(--app-shadow-lg); animation: slideIn 0.3s ease, fadeOut 0.3s ease forwards; max-width: 350px; }
.toast-success { background: var(--app-success); }
.toast-error { background: var(--app-danger); }
.toast-info { background: var(--app-primary); }

/* Theme switcher */
.theme-select { padding: 5px 10px; border-radius: 6px; border: 1px solid rgba(255,255,255,0.3); background: rgba(255,255,255,0.15); color: #fff; font-size: 0.83rem; font-family: inherit; cursor: pointer; }
.theme-select option { color: #333; background: #fff; }
.theme-actions-dropdown { position: relative; }
.theme-dropdown-menu { position: absolute; top: calc(100% + 4px); right: 0; background: var(--app-card); border: 1px solid var(--app-border); border-radius: 8px; box-shadow: var(--app-shadow-lg); min-width: 170px; z-index: 200; padding: 4px; animation: fadeIn 0.15s ease; }
.theme-dropdown-item { display: block; width: 100%; padding: 7px 12px; border: none; background: none; text-align: left; font-size: 0.83rem; font-family: inherit; cursor: pointer; border-radius: 4px; color: var(--app-text); }
.theme-dropdown-item:hover { background: var(--app-bg); }
.theme-dropdown-item.danger { color: var(--app-danger); }
.theme-dropdown-separator { height: 1px; background: var(--app-border); margin: 4px 8px; }

/* Import */
.import-textarea { width: 100%; min-height: 120px; font-family: 'SF Mono', 'Fira Code', monospace; font-size: 0.78rem; padding: 12px; border: 1px solid var(--app-border); border-radius: 6px; resize: vertical; }
.import-drop-zone { border: 2px dashed var(--app-border); border-radius: 8px; padding: 28px; text-align: center; color: var(--app-text-secondary); cursor: pointer; transition: all 0.2s; margin-bottom: 14px; }
.import-drop-zone:hover, .import-drop-zone.dragover { border-color: var(--app-primary); background: rgba(102,126,234,0.05); }

/* Empty state */
.empty-state { text-align: center; padding: 50px 20px; color: var(--app-text-secondary); }
.empty-state-icon { font-size: 2.5rem; margin-bottom: 10px; opacity: 0.4; }

/* Animations */
@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }
@keyframes slideUp { from { opacity: 0; transform: translateY(20px); } to { opacity: 1; transform: translateY(0); } }
@keyframes slideIn { from { opacity: 0; transform: translateX(40px); } to { opacity: 1; transform: translateX(0); } }
@keyframes fadeOut { 0%, 75% { opacity: 1; } 100% { opacity: 0; } }

/* Responsive */
@media (max-width: 1100px) {
  :root { --preview-width: 0px; }
  .preview-panel { display: none; }
}

@media (max-width: 800px) {
  :root { --sidebar-width: 56px; }
  .sidebar-item span:not(.sidebar-icon) { display: none; }
  .sidebar-count { display: none; }
  .sidebar-item { justify-content: center; padding: 10px; }
  .level-tab { padding: 6px 14px; }
  .level-tab small { display: none; }
  .header-actions .btn span { display: none; }
}

@media (max-width: 600px) {
  :root { --sidebar-width: 0px; --header-height: 50px; --level-tabs-height: 42px; }
  .sidebar { display: none; }
  .app-header h1 { font-size: 0.95rem; }
  .main-content { padding: 14px; }
  .modal { width: 95%; max-width: none; }
}

/* Scrollbar */
::-webkit-scrollbar { width: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #ccc; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #aaa; }