/* 课程正文与教学组件样式 */

.unit { display: grid; gap: 18px; padding-bottom: 8px; }
.prose { font-size: 17px; line-height: 1.85; color: var(--ink); overflow-wrap: anywhere; }
.prose > :first-child { margin-top: 0; }
.prose > :last-child { margin-bottom: 0; }
.prose p { margin: 0 0 14px; }
.prose ul, .prose ol { margin: 0 0 14px; padding-left: 1.6em; }
.prose li { margin: 4px 0; }
.prose li > p { margin: 0; }
.prose strong { font-weight: 700; color: #0E1722; }
.prose a { text-decoration: underline; text-underline-offset: 3px; }
.prose hr { border: 0; border-top: 1px solid var(--line); margin: 28px 0; }
.prose img { max-width: 100%; height: auto; }
.prose code { font-family: var(--mono); font-size: .88em; background: #EEF2F6; padding: 1px 6px; border-radius: 5px; }
.prose pre { background: #0F1B27; color: #E6EDF3; padding: 14px 16px; border-radius: 10px; overflow-x: auto; font-size: 14px; line-height: 1.6; }
.prose pre code { background: none; padding: 0; color: inherit; }
.prose blockquote { margin: 0 0 14px; padding: 8px 16px; border-left: 4px solid var(--blue-100); background: #F0F5F9; color: var(--ink-2); border-radius: 0 8px 8px 0; }
.prose blockquote > :last-child { margin-bottom: 0; }
.prose .katex { font-size: 1.06em; }
.prose .katex-display { margin: 14px 0; overflow-x: auto; overflow-y: hidden; padding: 4px 0; }

/* 章节标题 */
.unit h2 {
  font-size: 24px; font-weight: 800; margin: 44px 0 4px; padding-top: 4px; position: relative;
  display: flex; align-items: center; gap: 12px; scroll-margin-top: 120px; counter-increment: stage;
}
.unit { counter-reset: stage; }
.unit h2::before {
  content: counter(stage); flex: none; width: 32px; height: 32px; border-radius: 9px; background: var(--blue); color: #fff;
  font-size: 16px; display: grid; place-items: center;
}
.unit > h2:first-child { margin-top: 24px; }
.prose h2 { margin: 40px 0 8px; }
.prose h3 { font-size: 20px; font-weight: 700; margin: 30px 0 10px; scroll-margin-top: 120px; padding-left: 12px; border-left: 4px solid var(--amber); }
.prose h4 { font-size: 17px; font-weight: 700; margin: 22px 0 8px; scroll-margin-top: 120px; }
.prose h2 + h3 { margin-top: 14px; }

/* 表格 */
.table-wrap { overflow-x: auto; margin: 6px 0 18px; border: 1px solid var(--line); border-radius: 10px; background: #fff; -webkit-overflow-scrolling: touch; }
.table-wrap table { border-collapse: collapse; width: 100%; font-size: 15px; line-height: 1.6; min-width: 420px; }
.table-wrap th { background: var(--blue-50); color: var(--blue-700); font-weight: 700; text-align: left; white-space: nowrap; }
.table-wrap th, .table-wrap td { padding: 9px 14px; border-bottom: 1px solid var(--line-2); border-right: 1px solid var(--line-2); vertical-align: top; }
.table-wrap th:last-child, .table-wrap td:last-child { border-right: 0; }
.table-wrap tbody tr:last-child td { border-bottom: 0; }
.table-wrap tbody tr:nth-child(even) td { background: #FAFBFD; }
.prose table[border] , .prose table { border-collapse: collapse; }

/* 图示 */
figure.diagram { margin: 10px 0 6px; padding: 18px 14px; background: #fff; border: 1px solid var(--line); border-radius: 12px; overflow-x: auto; text-align: center; }
figure.diagram svg { max-width: 100%; height: auto; }
.diagram-body[aria-busy] { color: var(--muted); font-size: 14px; padding: 30px 0; }
.diagram-error { color: var(--red); font-size: 14px; margin-bottom: 8px; }
.diagram pre { text-align: left; font-size: 12px; }
.prose p.caption { text-align: center; color: var(--muted); font-size: 14px; margin: 0 0 18px; }
.prose p.caption em { font-style: normal; }

/* 学习目标 */
.objectives { background: linear-gradient(180deg, #F2F8FC, #fff); border: 1px solid var(--blue-100); border-radius: 14px; padding: 6px 20px; }
.objectives ul { list-style: none; margin: 0; padding: 0; }
.objectives li { display: grid; grid-template-columns: 56px 1fr; gap: 12px; padding: 12px 0; border-bottom: 1px dashed var(--blue-100); font-size: 16px; line-height: 1.7; }
.objectives li:last-child { border-bottom: 0; }
.obj-tag { height: 26px; align-self: start; margin-top: 1px; text-align: center; border-radius: 6px; font-size: 13px; font-weight: 700; line-height: 26px; background: var(--blue); color: #fff; }
.objectives li[data-kind="能力"] .obj-tag { background: #1E7F8C; }
.objectives li[data-kind="素养"] .obj-tag { background: #8A5A00; }

/* 提示块 */
.callout { border-radius: 12px; border: 1px solid var(--line); background: #fff; overflow: hidden; margin: 6px 0; }
.callout-head { display: flex; align-items: center; gap: 10px; padding: 9px 16px; font-weight: 700; font-size: 15px; }
.callout-label { font-size: 12.5px; padding: 1px 9px; border-radius: 5px; color: #fff; background: var(--blue); letter-spacing: .08em; }
.callout-body { padding: 4px 18px 14px; }
.callout-body.prose { font-size: 16.5px; }
.callout-keypoint { border-color: #F2D98A; background: #FFFBEB; }
.callout-keypoint .callout-label { background: #B07A00; }
.callout-keypoint .callout-head { color: #6B4A00; }
.callout-tip { border-color: #BFE3D0; background: #F2FAF6; }
.callout-tip .callout-label { background: var(--green); }
.callout-warn { border-color: #F2C4BF; background: #FFF6F5; }
.callout-warn .callout-label { background: var(--red); }
.callout-example { border-color: var(--blue-100); background: #F5F9FC; }
.callout-example .callout-label { background: var(--blue); }
.callout-case { border: 0; border-left: 5px solid var(--blue); border-radius: 0 12px 12px 0; background: #F0F5F9; box-shadow: var(--shadow-1); }
.callout-case .callout-label { background: var(--blue-700); }
.callout-case .callout-head { font-size: 17px; }
.callout-summary { border-color: #BFE3D0; background: #F2FAF6; }
.callout-summary .callout-label { background: var(--green); }

/* 思考 */
.think { border: 1px dashed #8FB4D0; border-radius: 12px; background: #F7FBFE; padding: 14px 18px 16px; display: grid; gap: 10px; justify-items: start; }
.think-label { font-size: 12.5px; font-weight: 700; color: var(--blue); background: var(--blue-50); padding: 1px 10px; border-radius: 5px; letter-spacing: .08em; }
.think-q { font-weight: 600; }
.think-a { background: #fff; border: 1px solid var(--line); border-left: 4px solid var(--green); border-radius: 8px; padding: 12px 16px; width: 100%; font-size: 16px; }
.think-a[hidden] { display: none; }

/* 作答框 */
.answer { width: 100%; display: grid; gap: 4px; }
.answer textarea { width: 100%; resize: vertical; min-height: 76px; border: 1px solid var(--line); background: #fff; border-radius: 9px; padding: 10px 12px; font: inherit; font-size: 16px; line-height: 1.7; color: var(--ink); }
.answer textarea:focus { outline: 3px solid #BCD9EE; border-color: var(--blue); }
.answer textarea::placeholder { color: #98A5B3; }
.answer-status { font-size: 12.5px; color: var(--muted); min-height: 18px; text-align: right; }

/* 测验 */
.quiz { background: #fff; border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px 18px; display: grid; gap: 12px; box-shadow: var(--shadow-1); }
.quiz-head { display: flex; align-items: center; gap: 10px; }
.quiz-no { font-weight: 800; color: var(--blue); }
.quiz-type { font-size: 12px; padding: 1px 9px; border-radius: 5px; background: var(--amber-50); color: var(--amber-700); font-weight: 700; }
.quiz-q { font-weight: 600; font-size: 17px; }
.quiz-opts { display: grid; gap: 8px; }
.quiz-opt { display: grid; grid-template-columns: 32px 1fr; gap: 12px; align-items: start; text-align: left; width: 100%; padding: 11px 14px; background: #fff; border: 1.5px solid var(--line); border-radius: 10px; font-size: 16px; line-height: 1.65; transition: border-color .12s, background .12s; }
.quiz-opt:hover:not(:disabled) { border-color: var(--blue); background: #F7FBFE; }
.opt-key { width: 28px; height: 28px; border-radius: 50%; border: 1.5px solid #B6C1CC; display: grid; place-items: center; font-weight: 700; font-size: 14px; color: var(--ink-2); }
.quiz-opt.is-picked { border-color: var(--blue); background: var(--blue-50); }
.quiz-opt.is-picked .opt-key { background: var(--blue); border-color: var(--blue); color: #fff; }
.quiz-opt:disabled { cursor: default; color: var(--ink); }
.quiz-opt.is-right { border-color: var(--green); background: var(--green-50); }
.quiz-opt.is-right .opt-key { background: var(--green); border-color: var(--green); color: #fff; }
.quiz-opt.is-wrong { border-color: var(--red); background: var(--red-50); }
.quiz-opt.is-wrong .opt-key { background: var(--red); border-color: var(--red); color: #fff; }
.quiz > .btn { justify-self: start; }
.quiz-feedback { border-radius: 10px; padding: 12px 16px; font-size: 16px; }
.quiz-feedback[hidden] { display: none; }
.quiz-feedback.is-correct { background: var(--green-50); border: 1px solid #BFE3D0; }
.quiz-feedback.is-incorrect { background: var(--red-50); border: 1px solid #F2C4BF; }
.quiz-feedback.is-ref { background: #F5F9FC; border: 1px solid var(--blue-100); }
.quiz-verdict { font-weight: 700; }
.is-correct .quiz-verdict { color: var(--green); } .is-incorrect .quiz-verdict { color: var(--red); }
.quiz-exp { margin-top: 6px; font-size: 15.5px; color: var(--ink-2); }
.quiz-ref strong { display: block; margin-bottom: 4px; color: var(--blue-700); }
.quiz-feedback .btn-text { margin-top: 6px; }

/* 实践 / 自评 / 拓展 */
.practice, .rubric { border: 1px solid var(--line); border-radius: 14px; background: #fff; padding: 18px 20px; display: grid; gap: 14px; }
.practice { border-color: #F2D98A; background: linear-gradient(180deg, #FFFCF0, #fff 40%); }
.practice-extend { border-color: #C9B8E8; background: linear-gradient(180deg, #F9F6FE, #fff 40%); }
.rubric { border-color: var(--blue-100); }
.practice-head { display: flex; align-items: center; gap: 10px; }
.practice-label { font-size: 12.5px; font-weight: 700; padding: 1px 10px; border-radius: 5px; background: #B07A00; color: #fff; letter-spacing: .08em; }
.practice-extend .practice-label { background: #6B4BB0; }
.rubric .practice-label { background: var(--blue); }
.practice-title { font-size: 18px; margin: 0; }
.field { display: grid; gap: 6px; }
.field-label { font-weight: 600; font-size: 16px; }
.practice-progress { font-size: 13px; color: var(--muted); }
.rubric-cell input { width: 72px; height: 34px; border: 1px solid var(--line); border-radius: 7px; padding: 0 8px; font: inherit; text-align: center; }
.rubric-cell input:focus { outline: 3px solid #BCD9EE; border-color: var(--blue); }
.rubric-total { font-weight: 800; color: var(--blue); text-align: right; font-size: 17px; }

@media (max-width: 720px) {
  .prose { font-size: 16.5px; }
  .unit h2 { font-size: 21px; }
  .objectives li { grid-template-columns: 1fr; gap: 4px; }
  .obj-tag { width: 52px; }
  .quiz, .practice, .rubric { padding: 16px; }
  .callout-body { padding: 2px 14px 12px; }
}