#ai-tutor-panel {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: #f0f2f5;
  flex-direction: column;
  font-family: 'Pretendard', 'Apple SD Gothic Neo', sans-serif;
}
#ai-tutor-panel.open {
  display: flex;
}

#ai-tutor-panel .at-header {
  background: linear-gradient(135deg, #4f46e5, #7c3aed);
  color: white;
  padding: 14px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
  flex-shrink: 0;
}
#ai-tutor-panel .at-header h1 {
  font-size: 18px;
  font-weight: 700;
}
#ai-tutor-panel .at-back-btn {
  background: rgba(255, 255, 255, 0.2);
  border: none;
  color: white;
  padding: 6px 12px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 14px;
}
#ai-tutor-panel .at-back-btn:hover {
  background: rgba(255, 255, 255, 0.3);
}
#ai-tutor-panel .at-usage-badge {
  margin-left: auto;
  background: rgba(255, 255, 255, 0.2);
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 12px;
}

#ai-tutor-panel .at-layout {
  display: flex;
  flex: 1;
  overflow: hidden;
}

/* 사이드바 */
#ai-tutor-panel .at-sidebar {
  width: 260px;
  background: white;
  border-right: 1px solid #e5e7eb;
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}
#ai-tutor-panel .at-sidebar-header {
  padding: 16px;
  border-bottom: 1px solid #f3f4f6;
}
#ai-tutor-panel .at-sidebar-header h2 {
  font-size: 14px;
  color: #6b7280;
  font-weight: 600;
  margin-bottom: 10px;
}
#ai-tutor-panel .at-new-chat-btn {
  width: 100%;
  padding: 10px;
  background: #4f46e5;
  color: white;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
}
#ai-tutor-panel .at-new-chat-btn:hover {
  background: #4338ca;
}
#ai-tutor-panel .at-subject-select {
  width: 100%;
  padding: 8px 10px;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  font-size: 13px;
  margin-top: 8px;
  background: white;
}
#ai-tutor-panel .at-session-list {
  flex: 1;
  overflow-y: auto;
  padding: 8px;
}
#ai-tutor-panel .at-session-item {
  padding: 10px 12px;
  border-radius: 10px;
  cursor: pointer;
  margin-bottom: 4px;
  border: 1px solid transparent;
  transition: all 0.15s;
}
#ai-tutor-panel .at-session-item:hover {
  background: #f9fafb;
  border-color: #e5e7eb;
}
#ai-tutor-panel .at-session-item.active {
  background: #eef2ff;
  border-color: #c7d2fe;
}
#ai-tutor-panel .at-s-title {
  font-size: 13px;
  font-weight: 500;
  color: #111827;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
#ai-tutor-panel .at-s-meta {
  font-size: 11px;
  color: #9ca3af;
  margin-top: 2px;
}
#ai-tutor-panel .at-s-del {
  float: right;
  color: #ef4444;
  background: none;
  border: none;
  cursor: pointer;
  font-size: 14px;
  display: none;
}
#ai-tutor-panel .at-session-item:hover .at-s-del {
  display: inline;
}

/* 채팅 */
#ai-tutor-panel .at-chat-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
#ai-tutor-panel .at-subject-banner {
  background: #eef2ff;
  padding: 8px 20px;
  font-size: 13px;
  color: #4f46e5;
  border-bottom: 1px solid #c7d2fe;
  flex-shrink: 0;
}
#ai-tutor-panel .at-messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}
#ai-tutor-panel .at-messages::-webkit-scrollbar {
  width: 6px;
}
#ai-tutor-panel .at-messages::-webkit-scrollbar-thumb {
  background: #d1d5db;
  border-radius: 3px;
}
#ai-tutor-panel .at-msg {
  display: flex;
  gap: 10px;
  max-width: 80%;
}
#ai-tutor-panel .at-msg.user {
  align-self: flex-end;
  flex-direction: row-reverse;
}
#ai-tutor-panel .at-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: #4f46e5;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  flex-shrink: 0;
}
#ai-tutor-panel .at-msg.user .at-avatar {
  background: #10b981;
}
#ai-tutor-panel .at-bubble {
  padding: 12px 16px;
  border-radius: 16px;
  font-size: 14px;
  line-height: 1.6;
  word-break: break-word;
}
#ai-tutor-panel .at-msg.ai .at-bubble {
  background: white;
  border: 1px solid #e5e7eb;
  border-radius: 4px 16px 16px 16px;
  color: #111827;
}
#ai-tutor-panel .at-msg.user .at-bubble {
  background: #4f46e5;
  color: white;
  border-radius: 16px 4px 16px 16px;
}
#ai-tutor-panel .at-bubble pre {
  background: #1e1e1e;
  color: #d4d4d4;
  padding: 12px;
  border-radius: 8px;
  overflow-x: auto;
  font-size: 13px;
  margin: 8px 0;
}
#ai-tutor-panel .at-bubble code {
  font-family: 'Consolas', monospace;
}
#ai-tutor-panel .at-bubble p {
  margin-bottom: 6px;
}
#ai-tutor-panel .at-bubble p:last-child {
  margin-bottom: 0;
}
#ai-tutor-panel .at-bubble ul,
#ai-tutor-panel .at-bubble ol {
  padding-left: 18px;
  margin: 6px 0;
}
#ai-tutor-panel .at-bubble strong {
  font-weight: 700;
}
#ai-tutor-panel .at-msg-time {
  font-size: 11px;
  color: #9ca3af;
  align-self: flex-end;
  flex-shrink: 0;
}

/* 타이핑 인디케이터 */
#ai-tutor-panel .at-typing .at-bubble {
  display: flex;
  gap: 4px;
  align-items: center;
  padding: 14px 18px;
}
#ai-tutor-panel .at-dot {
  width: 7px;
  height: 7px;
  background: #9ca3af;
  border-radius: 50%;
  animation: atBounce 1.2s infinite;
}
#ai-tutor-panel .at-dot:nth-child(2) {
  animation-delay: 0.2s;
}
#ai-tutor-panel .at-dot:nth-child(3) {
  animation-delay: 0.4s;
}
@keyframes atBounce {
  0%,
  60%,
  100% {
    transform: translateY(0);
  }
  30% {
    transform: translateY(-8px);
  }
}

/* 입력창 */
#ai-tutor-panel .at-input-area {
  padding: 10px 8px;
  background: white;
  border-top: 1px solid #e5e7eb;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex-shrink: 0;
}
#ai-tutor-panel #atMsgInput {
  flex: 1;
  border: 1.5px solid #e5e7eb;
  border-radius: 12px;
  padding: 10px 14px;
  font-size: 14px;
  resize: none;
  max-height: 120px;
  outline: none;
  transition: border-color 0.2s;
  font-family: inherit;
}
#ai-tutor-panel #atMsgInput:focus {
  border-color: #4f46e5;
}
#ai-tutor-panel .at-send-btn {
  background: #4f46e5;
  color: white;
  border: none;
  border-radius: 12px;
  width: 44px;
  height: 44px;
  cursor: pointer;
  font-size: 18px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s;
}
#ai-tutor-panel .at-send-btn:hover {
  background: #4338ca;
}
#ai-tutor-panel .at-send-btn:disabled {
  background: #c7d2fe;
  cursor: not-allowed;
}
#ai-tutor-panel .at-input-row {
  display: flex;
  gap: 10px;
  align-items: flex-end;
}
#ai-tutor-panel .at-attach-btn {
  background: #f3f4f6;
  border: 1.5px solid #e5e7eb;
  border-radius: 12px;
  width: 44px;
  height: 44px;
  cursor: pointer;
  font-size: 18px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s;
  color: #6b7280;
}
#ai-tutor-panel .at-attach-btn:hover {
  background: #e5e7eb;
}
#ai-tutor-panel .at-img-preview-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 2px 0;
}
#ai-tutor-panel .at-img-thumb {
  position: relative;
  width: 64px;
  height: 64px;
  border-radius: 8px;
  overflow: hidden;
  border: 1.5px solid #e5e7eb;
  flex-shrink: 0;
}
#ai-tutor-panel .at-img-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
#ai-tutor-panel .at-img-thumb .at-img-remove {
  position: absolute;
  top: 2px;
  right: 2px;
  width: 18px;
  height: 18px;
  background: rgba(0, 0, 0, 0.6);
  border-radius: 50%;
  color: white;
  font-size: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border: none;
  line-height: 1;
}
#ai-tutor-panel .at-bubble-imgs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 6px;
}
#ai-tutor-panel .at-bubble-imgs img {
  max-width: 180px;
  max-height: 180px;
  border-radius: 8px;
  object-fit: cover;
  cursor: pointer;
  display: block;
}

/* 환영 화면 */
#ai-tutor-panel .at-welcome {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 40px;
  text-align: center;
}
#ai-tutor-panel .at-welcome .at-emoji {
  font-size: 56px;
}
#ai-tutor-panel .at-welcome h2 {
  font-size: 22px;
  font-weight: 700;
  color: #111827;
}
#ai-tutor-panel .at-welcome p {
  color: #6b7280;
  font-size: 15px;
  max-width: 400px;
  line-height: 1.6;
}
#ai-tutor-panel .at-starter-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  max-width: 500px;
  margin-top: 8px;
}
#ai-tutor-panel .at-starter-btn {
  background: white;
  border: 1.5px solid #e5e7eb;
  border-radius: 12px;
  padding: 12px 16px;
  cursor: pointer;
  text-align: left;
  transition: all 0.15s;
  font-size: 13px;
  color: #374151;
}
#ai-tutor-panel .at-starter-btn:hover {
  border-color: #a5b4fc;
  background: #eef2ff;
  color: #4f46e5;
}
#ai-tutor-panel .at-starter-btn .at-se {
  font-size: 20px;
  display: block;
  margin-bottom: 4px;
}

/* 로그인 벽 */
#ai-tutor-panel .at-login-wall {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  color: #6b7280;
}

/* 학습 분석 뷰 */
#ai-tutor-panel .at-analytics-view {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  background: #f9fafb;
}
#ai-tutor-panel .at-stat-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
}
#ai-tutor-panel .at-stat-card {
  background: white;
  border-radius: 12px;
  padding: 14px 8px;
  text-align: center;
  border: 1px solid #e5e7eb;
}
#ai-tutor-panel .at-stat-num {
  font-size: 24px;
  font-weight: 700;
  color: #4f46e5;
}
#ai-tutor-panel .at-stat-label {
  font-size: 11px;
  color: #6b7280;
  margin-top: 2px;
}
#ai-tutor-panel .at-analysis-card {
  background: white;
  border-radius: 12px;
  padding: 16px;
  border: 1px solid #e5e7eb;
}
#ai-tutor-panel .at-section-title {
  font-size: 13px;
  font-weight: 700;
  color: #374151;
  margin-bottom: 10px;
}
#ai-tutor-panel .at-bar-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
}
#ai-tutor-panel .at-bar-label {
  width: 42px;
  font-size: 12px;
  color: #374151;
  flex-shrink: 0;
}
#ai-tutor-panel .at-bar-track {
  flex: 1;
  height: 10px;
  background: #f3f4f6;
  border-radius: 5px;
  overflow: hidden;
}
#ai-tutor-panel .at-bar-fill {
  height: 100%;
  border-radius: 5px;
  background: linear-gradient(90deg, #6366f1, #8b5cf6);
  transition: width 0.4s;
}
#ai-tutor-panel .at-bar-cnt {
  font-size: 11px;
  color: #9ca3af;
  flex-shrink: 0;
  min-width: 24px;
  text-align: right;
}
#ai-tutor-panel .at-week-grid {
  display: flex;
  gap: 6px;
  align-items: flex-end;
  height: 64px;
}
#ai-tutor-panel .at-day-col {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3px;
}
#ai-tutor-panel .at-day-bar {
  width: 100%;
  border-radius: 4px 4px 0 0;
  background: linear-gradient(180deg, #818cf8, #6366f1);
  min-height: 4px;
}
#ai-tutor-panel .at-day-label {
  font-size: 10px;
  color: #9ca3af;
  text-align: center;
}
#ai-tutor-panel .at-plan-btn-main {
  width: 100%;
  padding: 14px;
  background: linear-gradient(135deg, #4f46e5, #7c3aed);
  color: white;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  font-size: 15px;
  font-weight: 600;
  transition: opacity 0.2s;
}
#ai-tutor-panel .at-plan-btn-main:hover {
  opacity: 0.88;
}
#ai-tutor-panel .at-plan-btn-main:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}
#ai-tutor-panel .at-plan-result {
  background: white;
  border-radius: 12px;
  padding: 18px;
  border: 1.5px solid #c7d2fe;
  font-size: 14px;
  line-height: 1.75;
  color: #1e1b4b;
}
#ai-tutor-panel .at-plan-result h2 {
  font-size: 15px;
  font-weight: 700;
  margin: 14px 0 6px;
  color: #4f46e5;
}
#ai-tutor-panel .at-plan-result p {
  margin-bottom: 6px;
}
#ai-tutor-panel .at-plan-result ul,
#ai-tutor-panel .at-plan-result ol {
  padding-left: 18px;
  margin: 4px 0;
}
#ai-tutor-panel .at-plan-result strong {
  font-weight: 700;
}
/* 사이드바 도구 버튼 */
#ai-tutor-panel .at-sidebar-tools {
  display: flex;
  gap: 6px;
  margin-top: 8px;
}
#ai-tutor-panel .at-tool-btn {
  flex: 1;
  padding: 8px 4px;
  border-radius: 8px;
  border: 1.5px solid #e5e7eb;
  background: white;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  color: #374151;
  transition: all 0.15s;
  text-align: center;
}
#ai-tutor-panel .at-tool-btn:hover {
  border-color: #a5b4fc;
  background: #eef2ff;
  color: #4f46e5;
}
#ai-tutor-panel .at-tool-btn.active {
  background: #eef2ff;
  border-color: #6366f1;
  color: #4f46e5;
}

/* 관리자 뷰 */
#ai-tutor-panel .at-admin-view {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  background: #f9fafb;
}
#ai-tutor-panel .at-admin-section {
  background: white;
  border-radius: 14px;
  border: 1px solid #e5e7eb;
  padding: 18px;
}
#ai-tutor-panel .at-admin-section h3 {
  font-size: 14px;
  font-weight: 700;
  color: #374151;
  margin-bottom: 12px;
}
#ai-tutor-panel .at-admin-label {
  font-size: 12px;
  font-weight: 600;
  color: #6b7280;
  margin-bottom: 4px;
  display: block;
}
#ai-tutor-panel .at-admin-input {
  width: 100%;
  border: 1.5px solid #e5e7eb;
  border-radius: 10px;
  padding: 8px 12px;
  font-size: 13px;
  line-height: 1.5;
  resize: vertical;
  outline: none;
  color: #1f2937;
  box-sizing: border-box;
  margin-bottom: 10px;
  font-family: inherit;
}
#ai-tutor-panel .at-admin-input:focus {
  border-color: #6366f1;
}
#ai-tutor-panel .at-admin-save-btn {
  background: #6366f1;
  color: white;
  border: none;
  border-radius: 10px;
  padding: 9px 22px;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.15s;
}
#ai-tutor-panel .at-admin-save-btn:hover {
  background: #4f46e5;
}
#ai-tutor-panel .at-admin-save-btn:disabled {
  background: #a5b4fc;
  cursor: not-allowed;
}
#ai-tutor-panel .at-admin-stat-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 0;
  border-bottom: 1px solid #f3f4f6;
  font-size: 13px;
}
#ai-tutor-panel .at-admin-stat-row:last-child {
  border-bottom: none;
}
#ai-tutor-panel .at-admin-tabs {
  display: flex;
  gap: 6px;
  margin-bottom: 14px;
}
#ai-tutor-panel .at-admin-tab {
  flex: 1;
  padding: 8px;
  border-radius: 8px;
  border: 1.5px solid #e5e7eb;
  background: white;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  color: #6b7280;
  text-align: center;
  transition: all 0.15s;
}
#ai-tutor-panel .at-admin-tab.active {
  background: #eef2ff;
  border-color: #6366f1;
  color: #4f46e5;
}

@media (max-width: 640px) {
  #ai-tutor-panel .at-sidebar {
    display: none;
  }
  #ai-tutor-panel .at-msg {
    max-width: 92%;
  }
  #ai-tutor-panel .at-stat-cards {
    grid-template-columns: repeat(2, 1fr);
  }
}