/* ==================== 全局基础 ==================== */
*{box-sizing:border-box;}
html,body{
  margin:0;
  padding:0;
  font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  background:#f3f4f6;
  color:#111827;
}

/* 页面容器 */
.wrap{
  max-width:1200px;
  margin:0 auto;
  padding:16px 12px 40px;
}

h1{
  margin:8px 0 4px;
  font-size:1.8rem;
  font-weight:700;
}
.tagline{
  margin:0 0 18px;
  font-size:.9rem;
  color:#4b5563;
}

h2{
  margin:0 0 10px;
  font-size:1.1rem;
  font-weight:700;
}
.section-caption{
  margin:0 0 12px;
  font-size:.82rem;
  color:#6b7280;
}

/* 表单基础 */
label{
  display:block;
  font-size:.8rem;
  color:#374151;
  margin:8px 0 3px;
}
input,select{
  width:100%;
  padding:7px 9px;
  border-radius:6px;
  border:1px solid #d1d5db;
  font-size:.85rem;
  outline:none;
}
input:focus,select:focus{
  border-color:#2563eb;
  box-shadow:0 0 0 1px rgba(37,99,235,0.2);
}

.field-grid{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:8px 10px;
}

/* fieldset */
fieldset{
  border:1px solid #e5e7eb;
  border-radius:8px;
  padding:6px 8px 8px;
  margin-top:10px;
  background:#f9fafb;
}
legend{
  padding:0 4px;
  font-size:.78rem;
  color:#6b7280;
}

/* 单元选择按钮 */
.unit-row{
  display:flex;
  flex-wrap:wrap;
  gap:6px 10px;
  margin-top:4px;
}
.unit-row label{
  display:inline-flex;
  align-items:center;
  gap:5px;
  margin:0;
  padding:3px 7px;
  border-radius:999px;
  border:1px solid #e5e7eb;
  background:#ffffff;
  font-size:.8rem;
  cursor:pointer;
}
.unit-row input[type="checkbox"]{
  width:14px;
  height:14px;
  accent-color:#2563eb;
}

/* 按钮通用 */
.btn{
  border:none;
  border-radius:999px;
  padding:8px 14px;
  font-size:.86rem;
  font-weight:600;
  cursor:pointer;
  display:inline-flex;
  align-items:center;
  gap:4px;
}
.btn-primary{
  background:#2563eb;
  color:#ffffff;
}
.btn-secondary{
  background:#111827;
  color:#ffffff;
}
.btn-ghost{
  background:#ffffff;
  color:#111827;
  border:1px solid #d1d5db;
}

/* 通用 hint */
.hint{
  margin-top:8px;
  font-size:.78rem;
  color:#6b7280;
}

/* ==================== ABCD 测验结构 ==================== */

/* 题头 */
.quiz-header{
  display:flex;
  justify-content:space-between;
  align-items:flex-start;
  gap:12px;
  margin-bottom:10px;
  font-size:.86rem;
}
.quiz-title{
  font-weight:600;
}
.quiz-info{
  text-align:right;
  font-size:.8rem;
  color:#4b5563;
  min-width:220px;
}

/* 进度条 */
.quiz-progress-shell{
  width:100%;
  height:4px;
  border-radius:999px;
  background:rgba(148,163,184,0.35);
  overflow:hidden;
  margin:3px 0 4px;
}
.quiz-progress-bar{
  width:0%;
  height:100%;
  border-radius:999px;
  background:#22c55e;
  transition:width .18s ease-out;
}

.quiz-info-extra{
  display:flex;
  align-items:center;
  justify-content:flex-end;
  gap:6px;
  font-size:.8rem;
}
#quizStars{
  color:#facc15;
  font-weight:600;
}
.icon-toggle-btn{
  border:none;
  border-radius:999px;
  padding:3px 8px;
  font-size:.78rem;
  cursor:pointer;
  background:#e5e7eb;
  color:#111827;
}

/* 题卡 */
.quiz-question-card{
  border-radius:10px;
  border:1px solid #e5e7eb;
  background:#ffffff;
  padding:12px 14px 14px;
}

.quiz-stem-header{
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:8px;
  margin-bottom:4px;
  font-size:.82rem;
  color:#6b7280;
}
.icon-read-btn{
  border:none;
  border-radius:999px;
  padding:4px 10px;
  font-size:.78rem;
  cursor:pointer;
  background:#e5e7eb;
  color:#111827;
}

.quiz-stem{
  font-size:.9rem;
  font-weight:700;
  margin-bottom:8px;
  line-height:1.4;
}

/* 多图 PNG 容器 */
.quiz-images{
  display:none;
  margin-bottom:10px;
}
.quiz-images.money-combo{
  display:flex;
  flex-wrap:wrap;
  gap:8px;
  justify-content:center;
  align-items:center;
}
.quiz-images.money-four-sets{
  display:flex;
  gap:12px;
  justify-content:space-between;
}
.quiz-images.money-four-sets .money-set{
  flex:1 1 0;
  display:flex;
  flex-direction:column;
  align-items:center;
}
.quiz-images.money-four-sets .money-set-label{
  font-size:0.9rem;
  margin-bottom:4px;
  font-weight:600;
}
.quiz-images.money-four-sets .money-set-row{
  display:flex;
  flex-wrap:wrap;
  justify-content:center;
  gap:4px;
}
.quiz-images img{
  height:70px;
  object-fit:contain;
}

/* Canvas 区 */
#quizCanvas{
  width:100%;
  height:260px;
  border-radius:8px;
  border:1px solid #e5e7eb;
  background:#ffffff;
  display:none;
  margin-bottom:10px;
}

/* 单张图 PNG */
#quizImage {
  max-width:100%;
  max-height:260px;
  display:none;
  margin:0 auto 10px;
}

/* ABCD 选项 */
.quiz-options{
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:8px 10px;
  margin-top:6px;
}
.opt-btn{
  border-radius:999px;
  border:1px solid #d1d5db;
  background:#f9fafb;
  padding:8px 12px;
  font-size:.9rem;
  cursor:pointer;
  text-align:left;
  display:inline-flex;
  align-items:center;
  gap:6px;
}
.opt-btn span.opt-label{
  font-weight:700;
}
.opt-btn.correct{
  border-color:#16a34a;
  background:#dcfce7;
}
.opt-btn.wrong{
  border-color:#dc2626;
  background:#fee2e2;
}

/* 底部按钮 */
.quiz-footer{
  margin-top:10px;
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:8px;
  font-size:.8rem;
  color:#6b7280;
}
.quiz-footer button{
  border-radius:999px;
  border:1px solid #d1d5db;
  background:#ffffff;
  padding:6px 12px;
  font-size:.8rem;
  cursor:pointer;
}
.quiz-footer button:disabled{
  opacity:.4;
  cursor:default;
}

/* 打印区按钮 */
.actions-print{
  justify-content:flex-end;
}
.actions-print .btn{
  padding:6px 12px;
  font-size:.8rem;
}

/* 图片题（打印版兼容） */
.qimg-wrapper {
  display: flex;
  flex-direction: column;
  gap: 12px;
  justify-content: center;
  align-items: center;
  padding: 16px 0;
}
.qimg-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
}
.qimg-item {
  position: relative;
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.qimg-item img {
  max-width: 100%;
  max-height: 100%;
}
.qimg-item.removed img {
  filter: grayscale(100%);
  opacity: 0.35;
}
.qimg-item.removed::before,
.qimg-item.removed::after {
  content: "";
  position: absolute;
  left: 10%;
  right: 10%;
  top: 50%;
  height: 3px;
  background: #e11d48;
  transform-origin: center;
}
.qimg-item.removed::before {
  transform: translateY(-50%) rotate(45deg);
}
.qimg-item.removed::after {
  transform: translateY(-50%) rotate(-45deg);
}

/* 选项 layout 小屏幕兼容 */
@media (max-width:640px){
  .quiz-options{
    grid-template-columns:1fr;
  }
}