:root {
  --bg: var(--tg-theme-bg-color, #1a1a2e);
  --text: var(--tg-theme-text-color, #e0e0e0);
  --hint: var(--tg-theme-hint-color, #888);
  --btn: var(--tg-theme-button-color, #3a86ff);
  --btn-text: var(--tg-theme-button-text-color, #fff);
  --secondary-bg: var(--tg-theme-secondary-bg-color, #16213e);
  --danger: #e74c3c;
  --success: #2ecc71;
  --radius: 12px;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  padding-bottom: 20px;
}

/* Tabs */
.tabs {
  display: flex;
  background: var(--secondary-bg);
  padding: 4px;
  margin: 12px;
  border-radius: var(--radius);
  gap: 4px;
}

.tab {
  flex: 1;
  padding: 10px;
  border: none;
  background: transparent;
  color: var(--hint);
  font-size: 14px;
  font-weight: 600;
  border-radius: 10px;
  cursor: pointer;
  transition: all 0.2s;
}

.tab.active {
  background: var(--btn);
  color: var(--btn-text);
}

/* Panels */
.panel { display: none; padding: 0 12px; }
.panel.active { display: block; }

/* Dashboard */
.stat-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 10px;
  margin-bottom: 20px;
}

.stat-box {
  background: var(--secondary-bg);
  border-radius: var(--radius);
  padding: 16px;
  text-align: center;
}

.stat-num {
  font-size: 28px;
  font-weight: 700;
  color: var(--btn);
}

.stat-label {
  font-size: 11px;
  color: var(--hint);
  margin-top: 4px;
}

.info-card {
  background: var(--secondary-bg);
  border-radius: var(--radius);
  padding: 14px;
  margin-bottom: 10px;
}

.info-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--hint);
  margin-bottom: 8px;
}

.info-item {
  font-size: 14px;
  padding: 4px 0;
  color: var(--text);
}

.info-item .warn { color: var(--danger); }

/* Editor */
.section-block {
  background: var(--secondary-bg);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
}

.section-header {
  display: flex;
  align-items: center;
  padding: 12px 14px;
  cursor: pointer;
  gap: 10px;
}

.section-header:active { opacity: 0.7; }

.section-toggle {
  font-size: 12px;
  transition: transform 0.2s;
  color: var(--hint);
}

.section-toggle.open { transform: rotate(90deg); }

.section-title {
  flex: 1;
  font-size: 15px;
  font-weight: 600;
}

.section-count {
  font-size: 12px;
  color: var(--hint);
}

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

.icon-btn {
  background: none;
  border: none;
  color: var(--hint);
  font-size: 16px;
  cursor: pointer;
  padding: 4px;
}

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

.section-body {
  display: none;
  padding: 0 14px 12px;
}

.section-body.open { display: block; }

/* Theme */
.theme-block {
  background: var(--bg);
  border-radius: 8px;
  margin-bottom: 8px;
  overflow: hidden;
}

.theme-header {
  display: flex;
  align-items: center;
  padding: 10px 12px;
  cursor: pointer;
  gap: 8px;
}

.theme-title {
  flex: 1;
  font-size: 14px;
}

.theme-body {
  display: none;
  padding: 0 12px 10px;
}

.theme-body.open { display: block; }

/* Lesson */
.lesson-item {
  display: flex;
  align-items: center;
  padding: 8px 10px;
  background: var(--secondary-bg);
  border-radius: 6px;
  margin-bottom: 4px;
  gap: 8px;
  font-size: 13px;
}

.lesson-name { flex: 1; }

.lesson-url {
  font-size: 11px;
  color: var(--btn);
  max-width: 120px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* Add buttons */
.add-btn {
  display: block;
  width: 100%;
  padding: 10px;
  border: 1px dashed var(--hint);
  border-radius: 8px;
  background: transparent;
  color: var(--hint);
  font-size: 13px;
  cursor: pointer;
  margin-top: 8px;
  transition: all 0.2s;
}

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

/* Buttons */
.btn {
  padding: 10px 20px;
  border: none;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s;
}

.btn:active { transform: scale(0.97); }
.btn-primary { background: var(--btn); color: var(--btn-text); }
.btn-danger { background: var(--danger); color: white; }
.btn-secondary { background: var(--secondary-bg); color: var(--text); }

/* Modal */
.modal-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.6);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.modal-overlay.hidden { display: none; }

.modal {
  background: var(--bg);
  border-radius: var(--radius);
  padding: 20px;
  width: 90%;
  max-width: 360px;
  animation: modalIn 0.2s ease;
}

@keyframes modalIn {
  from { transform: scale(0.9); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

.modal-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 14px;
}

.modal-input {
  width: 100%;
  padding: 12px;
  border-radius: 8px;
  border: 1px solid var(--hint);
  background: var(--secondary-bg);
  color: var(--text);
  font-size: 15px;
  outline: none;
  margin-bottom: 10px;
}

.modal-input:focus { border-color: var(--btn); }

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