/* 知识测试 — 从 quiz-*-preview.html 合并 */

:root {
  --radius-card: 16px;
  --ok-soft: rgba(34, 197, 94, 0.12);
  --ok-border: rgba(34, 197, 94, 0.35);
  --ok-text: #15803d;
  --bad-soft: rgba(239, 68, 68, 0.1);
  --bad-border: rgba(239, 68, 68, 0.32);
  --bad-text: #b91c1c;
  --warn-soft: rgba(245, 158, 11, 0.12);
  --warn-text: #b45309;
}

.quiz-root {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 0;
  overflow: hidden;
}

.quiz-root[hidden] { display: none !important; }

.quiz-start-input {
  flex-shrink: 0;
  max-height: 320px;
  overflow: hidden;
  transition:
    transform 0.38s cubic-bezier(0.32, 1.12, 0.52, 1),
    opacity 0.28s ease,
    max-height 0.42s cubic-bezier(0.32, 1.12, 0.52, 1),
    padding 0.35s ease,
    visibility 0s linear 0.28s;
}

/* 模式切换 / 视图未就绪：避免闪出收窄条或开始底栏 */
.page.quiz-mode-exit #quiz-start-input,
.page.quiz-card-restore-pending #quiz-start-input,
.mode-quiz:not(.view-quiz-start):not(.view-quiz-card) #quiz-start-input {
  max-height: 0 !important;
  min-height: 0 !important;
  padding-top: 0 !important;
  padding-bottom: 0 !important;
  margin: 0 !important;
  opacity: 0 !important;
  visibility: hidden !important;
  pointer-events: none !important;
  transform: translateY(100%) !important;
  transition: none !important;
}

.mode-quiz.view-quiz-card #quiz-start-input {
  max-height: 0 !important;
  min-height: 0 !important;
  padding-top: 0 !important;
  padding-bottom: 0 !important;
  margin: 0 !important;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translateY(100%);
  overflow: hidden !important;
}

.page.is-quiz-view-instant.mode-quiz.view-quiz-card #quiz-start-input,
.page.is-quiz-view-instant.mode-quiz.view-quiz-start #quiz-start-input {
  transition: none !important;
}

@media (prefers-reduced-motion: reduce) {
  .quiz-start-input {
    transition: none !important;
  }
}

.quiz-start-box {
  overflow: hidden;
  transition: box-shadow 0.32s ease, border-color 0.2s ease;
}

.quiz-dock-handle {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  width: 100%;
  margin: 0 0 8px;
  min-height: 36px;
  padding: 8px 16px 6px;
  border: none;
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  background: linear-gradient(180deg, rgba(0, 0, 0, 0.02) 0%, rgba(0, 0, 0, 0.01) 100%);
  cursor: pointer;
  transition: background 0.2s ease, min-height 0.28s ease, padding 0.28s ease, margin 0.28s ease;
}

.quiz-dock-grip {
  display: block;
  width: 44px;
  height: 4px;
  border-radius: 999px;
  background: #c5cad4;
  transition: background 0.2s ease, width 0.2s ease;
}

.quiz-dock-handle-label {
  display: none;
  max-width: 100%;
  font-size: 12px;
  font-weight: 500;
  color: var(--text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.quiz-dock-handle-hint {
  font-size: 11px;
  line-height: 1;
  color: var(--text-secondary);
  letter-spacing: 0.04em;
  user-select: none;
}

.quiz-dock-handle:hover,
.quiz-dock-handle:focus-visible {
  background: linear-gradient(180deg, rgba(59, 111, 235, 0.08) 0%, rgba(59, 111, 235, 0.03) 100%);
  outline: none;
}

.quiz-dock-handle:hover .quiz-dock-grip,
.quiz-dock-handle:focus-visible .quiz-dock-grip {
  background: #aeb5c2;
  width: 48px;
}

.quiz-dock-body {
  padding: 0 12px 10px;
  transition: padding 0.28s cubic-bezier(0.32, 1.12, 0.52, 1);
}

.quiz-start-box.is-quiz-active:not(.is-expanded) .quiz-dock-body {
  display: none;
}

.quiz-start-box.is-quiz-active:not(.is-expanded) .quiz-dock-handle {
  margin-bottom: 6px;
  min-height: 28px;
  padding: 6px 16px 4px;
  gap: 2px;
}

.quiz-start-box.is-quiz-active:not(.is-expanded) .quiz-dock-handle-hint {
  display: none;
}

.quiz-start-box.is-quiz-active:not(.is-expanded) .quiz-dock-handle-label {
  display: block;
}

.quiz-start-box.is-quiz-active.is-expanded .quiz-dock-handle {
  background: linear-gradient(180deg, rgba(59, 111, 235, 0.1) 0%, rgba(59, 111, 235, 0.03) 100%);
}

.quiz-start-box.is-quiz-active.is-expanded .quiz-dock-grip {
  background: var(--brand);
  width: 48px;
}

.quiz-start-box.is-quiz-active.is-expanded .quiz-dock-handle-hint {
  color: var(--brand);
  font-weight: 500;
}

.mode-quiz.view-quiz-start .quiz-start-box .quiz-dock-handle {
  display: none;
}

.mode-quiz.view-quiz-start .quiz-start-box .quiz-dock-body {
  display: block;
  padding: 0;
}

.mode-quiz.view-quiz-card .quiz-start-box .quiz-dock-handle {
  display: none !important;
}

.mode-quiz.view-quiz-start #chat-body,
.mode-quiz.view-quiz-card #chat-body {
  display: grid !important;
  grid-template-areas: "stage";
  overflow: hidden;
}

.mode-quiz.view-quiz-card #message-list {
  display: flex !important;
  flex-direction: column;
  align-items: stretch;
  justify-content: flex-start;
  overflow-x: hidden;
  overflow-y: auto;
  overscroll-behavior: contain;
  padding: 0 !important;
  min-height: 0;
  -webkit-overflow-scrolling: touch;
}

.mode-quiz.view-quiz-card .quiz-legacy-shell {
  flex: 1 1 auto;
  min-height: 100%;
  margin: 0;
  align-self: stretch;
}

.mode-quiz.view-quiz-card .quiz-message {
  flex-shrink: 0;
  margin-top: auto;
  margin-bottom: auto;
}

/* —— 开始页（自 Next.js src/app/page 恢复） —— */

.mode-quiz .main {
  position: relative;
}

.main-content-track {
  position: relative;
  z-index: 1;
}

.quiz-scene-backdrop {
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.35s ease;
  overflow: hidden;
}

.mode-quiz .quiz-scene-backdrop {
  opacity: 1;
}

.mode-quiz.view-quiz-start:not(.quiz-shell-bg) .quiz-scene-backdrop {
  background:
    radial-gradient(circle at 8% 10%, rgba(37, 99, 235, 0.13), transparent 32%),
    radial-gradient(circle at 92% 18%, rgba(14, 165, 233, 0.12), transparent 34%),
    linear-gradient(135deg, #f8fafc 0%, #eef6ff 100%);
}

.mode-quiz.view-quiz-start:not(.quiz-shell-bg) .quiz-scene-backdrop::before {
  content: "";
  position: absolute;
  right: -120px;
  bottom: -240px;
  width: 520px;
  height: 520px;
  border-radius: 50%;
  opacity: 0.18;
  background:
    repeating-radial-gradient(circle, transparent 0 34px, rgba(37, 99, 235, 0.45) 35px 37px, transparent 38px 68px);
}

.mode-quiz.quiz-shell-bg .quiz-scene-backdrop,
.mode-quiz.view-quiz-card .quiz-scene-backdrop {
  background:
    radial-gradient(circle at 12% 0%, rgba(37, 99, 235, 0.15), transparent 30%),
    radial-gradient(circle at 92% 14%, rgba(14, 165, 233, 0.12), transparent 32%),
    linear-gradient(135deg, #f8fafc 0%, #eef6ff 100%);
}

.mode-quiz.quiz-shell-bg .quiz-scene-backdrop::before,
.mode-quiz.view-quiz-card .quiz-scene-backdrop::before {
  content: "";
  position: absolute;
  inset: 0;
  opacity: 0.58;
  background-image:
    linear-gradient(rgba(37, 99, 235, 0.055) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.055) 1px, transparent 1px);
  background-size: 3.25rem 3.25rem;
  mask-image: linear-gradient(to bottom, #000 0%, transparent 82%);
}

.mode-quiz.quiz-shell-bg .quiz-scene-backdrop::after,
.mode-quiz.view-quiz-card .quiz-scene-backdrop::after {
  content: "";
  position: absolute;
  top: -4rem;
  right: -6rem;
  width: 18rem;
  height: 28rem;
  opacity: 0.18;
  transform: rotate(16deg);
  background:
    repeating-radial-gradient(ellipse at center, transparent 0 16px, rgba(37, 99, 235, 0.38) 17px 18px, transparent 19px 34px);
}

.mode-quiz #quiz-start-input {
  display: none !important;
}

.mode-quiz.view-quiz-start .chat-body,
.mode-quiz.quiz-launch-active .chat-body {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px 20px 32px;
  overflow-y: auto;
}

.mode-quiz.view-quiz-start #welcome-quiz,
.mode-quiz.quiz-launch-active #quiz-launch-buffer {
  height: auto;
  min-height: 0;
  max-height: none;
  overflow: visible;
}

/* 开始页 / 加载缓冲：水平居中后上移面板自身宽度的 1/3 */
.mode-quiz.view-quiz-start .quiz-start-panel,
.mode-quiz.quiz-launch-active #quiz-launch-buffer {
  margin-top: calc(-1 * min(100%, 860px) / 3);
}

@keyframes quizStartPanelIn {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes quizStartPanelOut {
  from {
    opacity: 1;
    transform: translateY(0);
  }
  to {
    opacity: 0;
    transform: translateY(-28px);
  }
}

@keyframes quizStartCardIn {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.quiz-start-panel {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 340px);
  gap: 28px;
  align-items: stretch;
  width: min(100%, 860px);
  margin: 0 auto;
  padding: 28px;
  border: 1px solid rgba(37, 99, 235, 0.14);
  border-radius: 28px;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: 0 18px 48px rgba(15, 23, 42, 0.1);
  backdrop-filter: blur(18px);
  opacity: 0;
  animation: quizStartPanelIn 0.52s ease-out forwards;
}

.quiz-start-panel.quiz-start-panel-exit {
  animation: quizStartPanelOut 0.52s ease-out forwards;
  pointer-events: none;
}

.quiz-start-copy {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 260px;
}

.quiz-start-eyebrow {
  margin: 0 0 12px;
  color: #2563eb;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.14em;
}

.quiz-start-title {
  margin: 0;
  color: #0f172a;
  font-size: clamp(32px, 5vw, 46px);
  line-height: 1.08;
  font-weight: 860;
  letter-spacing: -0.06em;
  text-align: left;
}

.quiz-start-desc {
  max-width: 30rem;
  margin: 18px 0 0;
  color: #5f6f89;
  font-size: 16px;
  line-height: 1.72;
  text-align: left;
}

.quiz-start-card {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-height: 260px;
  padding: 22px;
  border: 1px solid rgba(37, 99, 235, 0.13);
  border-radius: 22px;
  background:
    radial-gradient(circle at 100% 0%, rgba(37, 99, 235, 0.12), transparent 42%),
    linear-gradient(180deg, #ffffff 0%, #f4f8ff 100%);
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.86);
  opacity: 0;
  animation: quizStartCardIn 0.48s ease-out 0.16s forwards;
}

.quiz-start-label {
  margin: 0 0 10px;
  color: #2563eb;
  font-size: 13px;
  font-weight: 780;
  letter-spacing: 0.04em;
}

.quiz-section-picker {
  position: relative;
}

.quiz-section-trigger {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  width: 100%;
  min-height: 48px;
  padding: 0 14px;
  border: 1px solid rgba(37, 99, 235, 0.22);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.92);
  color: #172033;
  font: inherit;
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  outline: none;
  transition:
    border-color 0.15s ease,
    box-shadow 0.15s ease,
    background 0.15s ease;
}

.quiz-section-trigger:hover {
  border-color: rgba(37, 99, 235, 0.38);
  background: #ffffff;
}

.quiz-section-trigger:focus-visible {
  border-color: rgba(37, 99, 235, 0.5);
  box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.1);
}

.quiz-section-trigger-text {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  text-align: left;
}

.quiz-section-trigger-icon {
  flex: 0 0 auto;
  color: #2563eb;
  font-size: 12px;
}

.quiz-section-menu {
  position: absolute;
  z-index: 30;
  top: calc(100% + 8px);
  left: 0;
  right: 0;
  max-height: 280px;
  margin: 0;
  padding: 8px;
  list-style: none;
  overflow: auto;
  border: 1px solid rgba(37, 99, 235, 0.16);
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.98);
  box-shadow: 0 18px 42px rgba(15, 23, 42, 0.14);
  backdrop-filter: blur(12px);
}

.quiz-section-menu.is-portaled {
  position: fixed;
  z-index: 100;
  top: auto;
  left: auto;
  right: auto;
}

.quiz-section-option {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  width: 100%;
  padding: 10px 12px;
  border: 1px solid transparent;
  border-radius: 12px;
  background: transparent;
  color: #172033;
  font: inherit;
  text-align: left;
  cursor: pointer;
  transition:
    background 0.12s ease,
    border-color 0.12s ease;
}

.quiz-section-option:hover {
  background: #eff6ff;
  border-color: rgba(37, 99, 235, 0.12);
}

.quiz-section-option-active {
  background: #eff6ff;
  border-color: rgba(37, 99, 235, 0.22);
}

.quiz-section-option-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  min-width: 1.7rem;
  height: 1.7rem;
  border-radius: 8px;
  background: rgba(37, 99, 235, 0.1);
  color: #2563eb;
  font-size: 12px;
  font-weight: 800;
}

.quiz-section-option-active .quiz-section-option-num {
  background: linear-gradient(135deg, #2b5cff, #1f4dde);
  color: #ffffff;
}

.quiz-section-option-label {
  flex: 1;
  min-width: 0;
  font-size: 14px;
  line-height: 1.45;
  font-weight: 600;
}

.quiz-start-actions {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 22px;
}

.quiz-continue-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 18px;
  border: 1px solid rgba(37, 99, 235, 0.22);
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.92);
  color: #2563eb;
  font: inherit;
  font-weight: 800;
  cursor: pointer;
}

.quiz-continue-btn:hover {
  border-color: rgba(37, 99, 235, 0.38);
  background: #ffffff;
}

.quiz-start-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 18px;
  border: none;
  border-radius: 14px;
  background: linear-gradient(135deg, #2b5cff, #1f4dde);
  color: #ffffff;
  font: inherit;
  font-weight: 800;
  cursor: pointer;
  box-shadow: 0 12px 26px rgba(37, 99, 235, 0.24);
}

.quiz-start-primary:hover {
  transform: translateY(-1px);
  box-shadow: 0 16px 32px rgba(37, 99, 235, 0.3);
}

/* 首页 → 章节：缓冲卡（对齐 LaunchBufferCard） */
.mode-quiz.quiz-launch-active #welcome-quiz {
  opacity: 0 !important;
  visibility: hidden !important;
  pointer-events: none !important;
}

.quiz-launch-buffer-wrap {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: center;
  align-items: center;
  width: 100%;
  padding: 0 20px;
  box-sizing: border-box;
}

.quiz-launch-buffer-wrap[hidden] {
  display: none !important;
}

.quiz-launch-buffer-card {
  width: min(100%, 860px);
  padding: 28px 32px;
  border: 1px solid rgba(37, 99, 235, 0.14);
  border-radius: 28px;
  background:
    radial-gradient(circle at 100% 0%, rgba(37, 99, 235, 0.12), transparent 42%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.96) 0%, #f4f8ff 100%);
  box-shadow: 0 18px 48px rgba(15, 23, 42, 0.1);
  backdrop-filter: blur(18px);
  text-align: center;
}

.quiz-launch-buffer-card-enter {
  opacity: 0;
  animation: quizLaunchBufferIn 0.52s ease-out forwards;
}

.quiz-launch-buffer-card-exit {
  animation: quizLaunchBufferOut 0.52s ease-out forwards;
  pointer-events: none;
}

@keyframes quizLaunchBufferIn {
  from {
    opacity: 0;
    transform: translateY(28px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes quizLaunchBufferOut {
  from {
    opacity: 1;
    transform: translateY(0);
  }
  to {
    opacity: 0;
    transform: translateY(-28px);
  }
}

.quiz-launch-buffer-eyebrow {
  margin: 0 0 10px;
  color: #2563eb;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.14em;
}

.quiz-launch-buffer-section {
  margin: 0;
  color: #0f172a;
  font-size: 1.15rem;
  line-height: 1.35;
  font-weight: 780;
  letter-spacing: -0.02em;
}

.quiz-launch-buffer-status {
  display: flex;
  align-items: baseline;
  justify-content: center;
  gap: 0;
  margin: 14px 0 0;
  color: #5f6f89;
  font-size: 0.92rem;
  font-weight: 650;
}

.quiz-launch-ellipsis::after {
  content: "…";
  display: inline-block;
  width: 1.2em;
  text-align: left;
  animation: quizLaunchEllipsis 1.2s steps(4, end) infinite;
}

@keyframes quizLaunchEllipsis {
  0% { content: ""; }
  25% { content: "."; }
  50% { content: ".."; }
  75% { content: "..."; }
}

/* 章节会话入场（对齐 quizSessionEnter*） */
@keyframes quizSessionSlideUpIn {
  from {
    opacity: 0;
    transform: translateY(26px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.quiz-legacy-shell.quiz-session-enter-boot .ql-header {
  opacity: 0;
  animation: quizSessionSlideUpIn 0.48s ease-out forwards;
}

.quiz-legacy-shell.quiz-session-enter-boot .ql-card,
.quiz-legacy-shell.quiz-session-enter-boot .ql-finished-card {
  opacity: 0;
  animation: quizSessionSlideUpIn 0.44s ease-out 0.12s forwards;
}

@media (prefers-reduced-motion: reduce) {
  .quiz-start-panel,
  .quiz-start-card {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .quiz-start-panel.quiz-start-panel-exit,
  .quiz-launch-buffer-card-enter,
  .quiz-launch-buffer-card-exit,
  .quiz-legacy-shell.quiz-session-enter-boot .ql-header,
  .quiz-legacy-shell.quiz-session-enter-boot .ql-card,
  .quiz-legacy-shell.quiz-session-enter-boot .ql-finished-card {
    animation: none;
    opacity: 1;
    transform: none;
  }

  .quiz-launch-ellipsis::after {
    animation: none;
    content: "…";
  }
}

@media (max-width: 720px) {
  .mode-quiz.view-quiz-start .chat-body,
  .mode-quiz.quiz-launch-active .chat-body {
    padding: 16px 14px 24px;
  }

  .mode-quiz.view-quiz-start .quiz-start-panel,
  .mode-quiz.quiz-launch-active #quiz-launch-buffer {
    margin-top: calc(-1 * min(100%, 860px) / 3);
  }

  .quiz-start-panel {
    grid-template-columns: 1fr;
    padding: 22px;
  }

  .quiz-start-copy,
  .quiz-start-card {
    min-height: auto;
  }

  .quiz-start-card {
    animation-delay: 0.22s;
  }
}

.quiz-stage {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow-y: auto;
  padding: 24px 20px 40px;
  min-height: 0;
}

.quiz-stage[hidden] { display: none !important; }

/* 测验题卡：对话气泡容器（外壳与助手亚克力同款，切换题/解析不重建） */
.quiz-message {
  align-self: flex-start;
  width: min(92%, 680px);
  max-width: min(92%, 680px);
}

.message-assistant .message-bubble.quiz-message-bubble {
  padding: 0;
  overflow: hidden;
}

.quiz-message-bubble > .quiz-card,
.quiz-message-bubble .quiz-card-viewport .quiz-card {
  width: 100%;
  background: transparent;
  border: none;
  border-radius: 0;
  box-shadow: none;
}

/* 题卡内左右切换：新卡叠层滑入，避免双卡半宽重排闪烁 */
.quiz-card-viewport {
  position: relative;
  width: 100%;
  overflow: hidden;
  transition: height 0.32s cubic-bezier(0.32, 1.08, 0.52, 1);
}

@media (prefers-reduced-motion: reduce) {
  .quiz-card-viewport {
    transition: none;
  }
}

.quiz-card-track {
  position: relative;
  width: 100%;
}

.quiz-card-track.is-duo > .quiz-card-slide-out {
  position: relative;
  z-index: 1;
  width: 100%;
  transform: translateX(0);
  opacity: 1;
  pointer-events: none;
  transition:
    transform 0.28s cubic-bezier(0.32, 1.08, 0.52, 1),
    opacity 0.22s ease;
}

.quiz-card-track.is-duo > .quiz-card-slide-in {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 2;
  width: 100%;
  transform: translateX(100%);
  pointer-events: auto;
  transition: transform 0.28s cubic-bezier(0.32, 1.08, 0.52, 1);
}

.quiz-card-track.is-sliding-forward > .quiz-card-slide-out {
  transform: translateX(-16%);
  opacity: 0;
}

.quiz-card-track.is-sliding-forward > .quiz-card-slide-in {
  transform: translateX(0);
}

.quiz-card-track.is-duo > .quiz-card-slide-in-from-left {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 2;
  width: 100%;
  transform: translateX(-100%);
  pointer-events: auto;
  transition: transform 0.28s cubic-bezier(0.32, 1.08, 0.52, 1);
}

.quiz-card-track.is-sliding-backward > .quiz-card-slide-out {
  transform: translateX(16%);
  opacity: 0;
}

.quiz-card-track.is-sliding-backward > .quiz-card-slide-in-from-left {
  transform: translateX(0);
}

.quiz-card-track > .quiz-card-stashed-left {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
  width: 100%;
  transform: translateX(-100%);
  opacity: 0;
  pointer-events: none;
}

.quiz-card-track > .quiz-card-stashed-right {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
  width: 100%;
  transform: translateX(100%);
  opacity: 0;
  pointer-events: none;
}

.quiz-card.is-feedback-peek .options .option {
  pointer-events: none;
}

.quiz-card.is-feedback-peek .btn-dont-know,
.quiz-card.is-feedback-peek .btn-skip {
  visibility: hidden;
  pointer-events: none;
}

.quiz-card .btn-back-feedback {
  margin-right: auto;
}

.quiz-card-track:not(.is-duo) > .quiz-card {
  width: 100%;
}

@media (prefers-reduced-motion: reduce) {
  .quiz-card-track.is-duo > .quiz-card-slide-out,
  .quiz-card-track.is-duo > .quiz-card-slide-in,
  .quiz-card-track.is-duo > .quiz-card-slide-in-from-left {
    transition: none;
  }
}

.quiz-message-bubble .card-header {
  background: transparent;
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.quiz-card {
  width: min(520px, 100%);
  background: var(--main-bg);
  border: 1px solid var(--brand-border);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-input);
  overflow: hidden;
}

.quiz-card .card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 18px 12px;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, #fafbfc 0%, var(--main-bg) 100%);
}

.quiz-card .card-header-left {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 500;
}

.quiz-card .card-header-icon {
  width: 16px;
  height: 16px;
  color: var(--brand);
}

.quiz-card .card-pagination {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  color: var(--text-muted);
}

.quiz-card .card-pagination span {
  min-width: 48px;
  text-align: center;
  font-size: 12px;
  color: var(--text-secondary);
}

.quiz-card .card-meta { font-size: 12px; color: var(--text-muted); }

.quiz-card .card-body { padding: 20px 18px 10px; }

.quiz-card .question-text {
  font-size: 15px;
  line-height: 1.65;
  font-weight: 500;
  color: var(--text);
  margin-bottom: 16px;
}

.quiz-card .options {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.quiz-card .option {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  width: 100%;
  padding: 11px 14px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--main-bg);
  text-align: left;
  color: var(--text);
  line-height: 1.5;
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease, box-shadow 0.15s ease;
}

.quiz-card .option:hover {
  border-color: var(--brand-border);
  background: #fafbfc;
}

.quiz-card .option.is-selected {
  background: var(--brand-soft);
  border-color: rgba(59, 111, 235, 0.45);
  box-shadow: 0 2px 8px rgba(59, 111, 235, 0.08);
}

.quiz-card .option-letter {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  margin-top: 1px;
  border: 1px solid var(--brand-border);
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  background: linear-gradient(180deg, #ffffff 0%, #f8f9fc 100%);
}

.quiz-card .option.is-selected .option-letter {
  border-color: var(--brand);
  color: #fff;
  background: var(--brand);
}

.quiz-card .option-label {
  flex: 1;
  font-size: 14px;
  color: var(--text-secondary);
}

.quiz-card .option.is-selected .option-label {
  color: var(--text);
  font-weight: 500;
}

.quiz-card .card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 18px 18px;
}

.quiz-card .card-footer-actions {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-left: auto;
}

.quiz-card .btn-dont-know,
.quiz-card .btn-skip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 10px;
  border: none;
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
}

.quiz-card .btn-dont-know {
  color: #e5484d;
  background: var(--sidebar-bg, rgba(0, 0, 0, 0.06));
}

.quiz-card .btn-skip {
  color: var(--text-muted);
  background: transparent;
}

.quiz-card .btn-skip kbd {
  font-size: 11px;
  color: var(--text-muted);
  font-family: inherit;
  padding: 1px 5px;
  border-radius: 4px;
  background: var(--sidebar-bg);
}

.quiz-card .btn-continue,
.quiz-card .btn-next {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border: none;
  border-radius: 999px;
  background: var(--brand);
  color: #fff;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 2px 10px var(--brand-shadow);
}

.quiz-card .btn-continue:disabled,
.quiz-card .btn-next:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.quiz-card .verdict {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 600;
  margin-bottom: 14px;
}

.quiz-card .verdict.is-ok {
  background: var(--ok-soft);
  border: 1px solid var(--ok-border);
  color: var(--ok-text);
}

.quiz-card .verdict.is-bad {
  background: var(--bad-soft);
  border: 1px solid var(--bad-border);
  color: var(--bad-text);
}

.quiz-card .answer-row {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 16px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  background: var(--sidebar-bg);
  font-size: 13px;
  line-height: 1.5;
}

.quiz-card .answer-row-label { flex-shrink: 0; color: var(--text-muted); }
.quiz-card .answer-row-value { color: var(--text); font-weight: 500; }
.quiz-card .answer-row-value strong { color: var(--brand); font-weight: 700; }

.quiz-card .explain-block { border-top: 1px solid var(--border); padding-top: 14px; }

.quiz-card .explain-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 10px;
}

.quiz-card .explain-label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 600;
  color: var(--brand);
  letter-spacing: 0.04em;
}

.quiz-card .explain-toggle {
  display: inline-flex;
  align-items: center;
  gap: 2px;
  padding: 4px 2px;
  border: none;
  background: transparent;
  font: inherit;
  font-size: 12px;
  color: var(--text-muted);
  cursor: pointer;
}

.quiz-card .explain-block.has-overflow .explain-toggle {
  font-size: 14px;
  font-weight: 500;
  color: var(--brand);
}

.quiz-card .explain-block.fits .explain-toggle {
  display: none;
}

.quiz-card .explain-toggle:hover { color: var(--brand); }

.quiz-card .explain-chevron {
  flex-shrink: 0;
  transition: transform 0.2s ease;
}
.quiz-card .explain-block.is-expanded .explain-chevron { transform: rotate(180deg); }

.quiz-card .explain-body-wrap {
  position: relative;
  overflow: hidden;
  transition: max-height 0.28s ease;
}

@media (prefers-reduced-motion: reduce) {
  .quiz-card .explain-body-wrap {
    transition: none;
  }
}

.quiz-card .explain-text.is-clamped {
  overflow: hidden;
  word-break: break-word;
}

/* 单段解析：4 行截断 + 省略号 */
.quiz-card .explain-text.is-clamped > p:only-child {
  display: -webkit-box;
  -webkit-box-orient: vertical;
  -webkit-line-clamp: 4;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 折叠态仅靠 line-clamp / max-height 截断，不用底部渐变遮罩 */
.quiz-card .explain-collapse-hint {
  display: none !important;
}

.quiz-card .explain-text {
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-secondary);
}

.quiz-card .explain-text p + p { margin-top: 10px; }

.quiz-card .explain-text .answer-figure {
  margin: 10px 0;
}

.quiz-card .answer-fig-caption {
  margin-top: 6px;
  font-size: 12px;
  line-height: 1.5;
  color: var(--text-muted);
  text-align: center;
}

.quiz-card .card-footer-feedback {
  justify-content: space-between;
}

.quiz-card .btn-ghost {
  padding: 8px 6px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-size: 13px;
  cursor: pointer;
}

.quiz-card.score-card .card-body {
  padding: 20px 18px 16px;
  text-align: center;
}

.quiz-card .result-badge {
  display: inline-flex;
  padding: 4px 10px;
  margin-bottom: 10px;
  border-radius: 999px;
  background: var(--brand-soft);
  border: 1px solid var(--brand-border);
  color: var(--brand);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.quiz-card .result-title {
  font-size: 20px;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.quiz-card .result-section {
  margin-top: 6px;
  font-size: 13px;
  color: var(--text-secondary);
}

.quiz-card .score-panel {
  display: grid;
  grid-template-columns: auto 1fr;
  align-items: center;
  gap: 16px;
  margin-top: 18px;
  padding: 14px;
  text-align: left;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: linear-gradient(180deg, #fafbfc 0%, var(--main-bg) 100%);
}

.quiz-card .score-dial {
  position: relative;
  width: 104px;
  height: 104px;
  flex-shrink: 0;
}

.quiz-card .score-ring {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  overflow: visible;
  pointer-events: none;
}

.quiz-card .score-ring-track,
.quiz-card .score-ring-value {
  fill: none;
  stroke-width: 7;
}

.quiz-card .score-ring-track { stroke: #ececef; }

.quiz-card .score-ring-value {
  stroke: var(--brand);
  stroke-linecap: round;
  transform: rotate(-90deg);
  transform-origin: 60px 60px;
}

.quiz-card .score-dial-inner {
  position: absolute;
  inset: 0;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.quiz-card .score-fraction {
  display: inline-flex;
  align-items: baseline;
  line-height: 1;
  white-space: nowrap;
}

.quiz-card .score-value {
  font-size: 26px;
  font-weight: 700;
  color: var(--brand);
}

.quiz-card .score-total {
  margin-left: 1px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-muted);
}

.quiz-card .score-copy-label { font-size: 12px; color: var(--text-muted); }

.quiz-card .score-mastery {
  margin-top: 4px;
  font-size: 16px;
  font-weight: 600;
  color: var(--ok-text);
}

.quiz-card .score-hint {
  margin-top: 6px;
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.5;
}

.quiz-card .insight-box {
  margin-top: 14px;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  background: var(--warn-soft);
  border: 1px solid rgba(245, 158, 11, 0.28);
  text-align: left;
}

.quiz-card .insight-label {
  font-size: 12px;
  font-weight: 600;
  color: var(--warn-text);
}

.quiz-card .insight-text {
  margin-top: 6px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--text-secondary);
}

.quiz-card .nav-row {
  display: flex;
  gap: 10px;
  margin-bottom: 10px;
}

.quiz-card .nav-btn {
  flex: 1;
  min-height: 40px;
  border: 1px solid var(--brand-border);
  border-radius: var(--radius-sm);
  background: var(--main-bg);
  color: var(--brand);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
}

.quiz-card .nav-btn:disabled {
  color: var(--text-muted);
  border-color: var(--border);
  background: var(--sidebar-bg);
  cursor: not-allowed;
}

.quiz-card .retry-btn {
  width: 100%;
  min-height: 42px;
  border: none;
  border-radius: 999px;
  background: var(--brand);
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  box-shadow: 0 2px 10px var(--brand-shadow);
}

@media (max-width: 420px) {
  .quiz-card .score-panel {
    grid-template-columns: 1fr;
    justify-items: center;
    text-align: center;
  }
}