:root {
  --bg-app: #0f172a;
  --bg-panel: #1e293b;
  --bg-input: #020617;
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --primary: #6366f1;
  --primary-hover: #4f46e5;
  --border: #334155;
  --success: #10b981;
  --danger: #ef4444;
  --radius: 12px;
  --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --header-height: 64px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background-color: var(--bg-app);
  color: var(--text-main);
  font-family:
    "Inter",
    system-ui,
    -apple-system,
    sans-serif;
  -webkit-font-smoothing: antialiased;
  height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Layout */
.app-container {
  display: flex;
  height: 100%;
  overflow: hidden;
}

.sidebar {
  width: 260px;
  background-color: var(--bg-panel);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: 24px 16px;
  flex-shrink: 0;
}

.main-content {
  flex: 1;
  overflow-y: auto;
  padding: 32px;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

/* Sidebar */
.app-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 32px;
  padding-left: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.app-title svg {
  color: var(--primary);
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px;
  color: var(--text-muted);
  border-radius: 8px;
  cursor: pointer;
  transition: all 0.2s;
  margin-bottom: 4px;
  font-size: 14px;
  font-weight: 500;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
}

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

.nav-item.active {
  background-color: var(--primary);
  color: white;
}

.nav-divider {
  height: 1px;
  background-color: var(--border);
  margin: 16px 0;
}

/* Panels */
.panel {
  display: none;
  animation: fadeIn 0.3s ease;
}

.panel.active {
  display: block;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Cards & Inputs */
.card {
  background-color: var(--bg-panel);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: var(--shadow);
}

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

.card-title {
  font-size: 18px;
  font-weight: 600;
  margin: 0;
}

label {
  display: block;
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 8px;
  font-weight: 500;
}

input,
textarea,
select {
  width: 100%;
  background-color: var(--bg-input);
  border: 1px solid var(--border);
  color: var(--text-main);
  border-radius: 8px;
  padding: 10px 12px;
  font-size: 14px;
  transition: border-color 0.2s;
  font-family: inherit;
}

textarea {
  min-height: 120px;
  resize: vertical;
  line-height: 1.6;
}

input:focus,
textarea:focus,
select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 2px rgba(99, 102, 241, 0.2);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
  border: 1px solid transparent;
}

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

.btn-primary:hover:not(:disabled) {
  background-color: var(--primary-hover);
}

.btn-secondary {
  background-color: transparent;
  border-color: var(--border);
  color: var(--text-main);
}

.btn-secondary:hover:not(:disabled) {
  background-color: rgba(255, 255, 255, 0.05);
}

.btn-icon {
  width: 36px;
  height: 36px;
  padding: 0;
  border-radius: 50%;
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-danger {
  background-color: rgba(239, 68, 68, 0.1);
  color: var(--danger);
  border-color: rgba(239, 68, 68, 0.2);
}

.btn-danger:hover {
  background-color: rgba(239, 68, 68, 0.2);
}

/* Output Area */
.output-area {
  background-color: #000000;
  border-radius: 8px;
  padding: 16px;
  min-height: 200px;
  font-size: 14px;
  line-height: 1.7;
  color: #e2e8f0;
}

.output-area h1,
.output-area h2,
.output-area h3 {
  color: var(--text-main);
  margin-top: 1.5em;
}

.output-area strong {
  color: var(--primary);
}

/* Knowledge Base List */
.kb-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}

.kb-item {
  background-color: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 16px;
  transition: transform 0.2s;
}

.kb-item:hover {
  transform: translateY(-2px);
  border-color: var(--primary);
}

.kb-cat {
  font-size: 12px;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 8px;
  font-weight: 700;
}

.kb-q {
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-main);
}

.kb-a {
  font-size: 14px;
  color: var(--text-muted);
}

/* Filters */
.filters {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.filter-chip {
  padding: 6px 12px;
  border-radius: 20px;
  font-size: 12px;
  background-color: var(--bg-input);
  border: 1px solid var(--border);
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s;
}

.filter-chip.active {
  background-color: var(--primary);
  color: white;
  border-color: var(--primary);
}

/* Admin Table */
.table-container {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

th,
td {
  padding: 12px;
  text-align: left;
  border-bottom: 1px solid var(--border);
}

th {
  color: var(--text-muted);
  font-weight: 500;
}

td {
  color: var(--text-main);
}

/* Loading */
.loading-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.9);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  backdrop-filter: blur(4px);
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid rgba(99, 102, 241, 0.3);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

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

.hidden {
  display: none !important;
}

/* Settings Modal */
.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 900;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s;
}

.modal-backdrop.visible {
  opacity: 1;
  pointer-events: auto;
}

.modal-content {
  background: var(--bg-panel);
  width: 100%;
  max-width: 500px;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
  padding: 24px;
  transform: scale(0.95);
  transition: transform 0.2s;
}

.modal-backdrop.visible .modal-content {
  transform: scale(1);
}

.form-group {
  margin-bottom: 16px;
}

.form-help {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 4px;
}

/* Responsive */
@media (max-width: 768px) {
  .app-container {
    flex-direction: column;
  }
  .sidebar {
    width: 100%;
    padding: 12px;
    flex-direction: row;
    align-items: center;
    overflow-x: auto;
  }
  .app-title {
    margin-bottom: 0;
    margin-right: 24px;
    font-size: 16px;
  }
  .nav-item {
    padding: 8px;
    width: auto;
    white-space: nowrap;
  }
  .nav-divider {
    display: none;
  }
  .main-content {
    padding: 16px;
  }
}