/* M-77 习题集自助导入：沿用教师端 token、按钮与抽屉，不影响班级资料上传。 */
.ro-book-head{display:flex;align-items:center;justify-content:space-between;gap:16px;margin:14px 0 10px}
.ro-book-head p{margin:0;color:var(--muted);font-size:14px;line-height:1.6}
.ro-book-head .btn{flex:none}
.mbi{display:flex;flex-direction:column;gap:20px;padding:24px;min-height:100%;font-size:14px;color:var(--ink)}
.mbi-head h2{margin:0 0 6px;font-size:24px;line-height:1.3}
.mbi-head p{margin:0;color:var(--muted);line-height:1.6}
.mbi-steps{display:flex;gap:16px;border-bottom:1px solid var(--line);padding-bottom:14px;color:var(--faint);font-size:13px;flex-wrap:wrap}
.mbi-steps b{color:var(--pri-t)}
.mbi-form{display:flex;flex-direction:column;gap:16px;max-width:660px}
.mbi-form .field{display:flex;flex-direction:column;gap:6px}
.mbi-form .field>span{font-weight:600}
.mbi-form input,.mbi-form select{min-height:42px}
.mbi-file{display:flex;align-items:center;gap:12px;min-height:54px;flex-wrap:wrap;border-bottom:1px solid var(--line)}
.mbi-file[hidden]{display:none}
.mbi-file b{min-width:130px}
.mbi-file span{min-width:0;overflow-wrap:anywhere;color:var(--muted)}
.mbi-help{margin:0;color:var(--muted);line-height:1.7;max-width:72ch}
.mbi-error{margin:0;padding:12px 14px;border-radius:var(--r-sm);background:var(--bad-s);color:var(--bad-d);line-height:1.6}
.mbi-note{margin:0;padding:10px 0;color:var(--amber-d);display:flex;align-items:center;gap:12px;flex-wrap:wrap}
.mbi-answer-source{display:flex;align-items:center;gap:12px;flex-wrap:wrap;padding:12px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.mbi-answer-source>div{flex:1 1 260px}
.mbi-answer-source p{margin:4px 0 0;color:var(--muted);line-height:1.6}
.mbi-progress{margin:0;color:var(--pri-t);font-size:16px;font-weight:600}
.mbi-actions{display:flex;align-items:center;gap:10px;flex-wrap:wrap;margin-top:auto;padding-top:12px}
.mbi-resume{border-top:1px solid var(--line);padding-top:16px}
.mbi-resume h3{margin:0 0 10px;font-size:16px}
.mbi-resume>p{color:var(--faint);margin:0}
.mbi-resume-row{width:100%;min-height:48px;border:0;border-bottom:1px solid var(--line);background:transparent;text-align:left;display:flex;align-items:center;justify-content:space-between;gap:12px;color:var(--ink);font:inherit}
.mbi-resume-row:hover{color:var(--pri-t);background:var(--soft)}
.mbi-resume-row small{color:var(--muted)}
.mbi-summary{display:flex;gap:8px;flex-wrap:wrap}
.mbi-summary strong{padding:8px 12px;border-radius:var(--r-sm);background:var(--pri-s);color:var(--pri-t);font-size:13px}
.mbi-summary .bad{background:var(--bad-s);color:var(--bad-d)}
.mbi-list{display:flex;flex-direction:column;gap:12px;max-height:60vh;overflow:auto}
.mbi-group{background:var(--soft);border-radius:var(--r-sm)}
.mbi-group summary{cursor:pointer;min-height:48px;padding:12px 14px;font-weight:600;list-style:none}
.mbi-group summary small{margin-left:8px;color:var(--muted);font-weight:400}
.mbi-group summary::-webkit-details-marker{display:none}
.mbi-question{padding:14px;background:var(--panel);border-top:1px solid var(--line)}
.mbi-question-head{display:flex;align-items:baseline;gap:10px;flex-wrap:wrap}
.mbi-question-head small{color:var(--faint);font-size:12px;overflow-wrap:anywhere}
.mbi-images{display:flex;align-items:flex-start;gap:12px;flex-wrap:wrap;margin:10px 0}
.mbi-images img{display:block;max-width:min(100%,520px);max-height:310px;object-fit:contain;background:#fff;border:1px solid var(--line2);border-radius:var(--r-xs)}
.mbi-question-actions{display:flex;align-items:center;gap:14px;flex-wrap:wrap}
.mbi-question-actions label{display:flex;align-items:center;gap:8px;min-height:44px;cursor:pointer}
.mbi-question-actions input{width:18px;height:18px;accent-color:var(--pri)}
.mbi-crop-editor{padding:16px;border:2px solid var(--pri);border-radius:var(--r-sm);background:var(--panel)}
.mbi-crop-editor h3{margin:0 0 8px;font-size:18px}
.mbi-crop-parts{display:flex;gap:16px;overflow-x:auto;margin-top:16px}
.mbi-crop-part{flex:0 0 min(100%,540px);min-width:0}
.mbi-crop-part>b{display:block;margin-bottom:8px}
.mbi-crop-canvas{position:relative;width:fit-content;max-width:100%;border:1px solid var(--line2);background:#fff}
.mbi-crop-canvas img{display:block;max-width:100%;width:520px;height:auto;touch-action:none;cursor:crosshair;user-select:none}
.mbi-crop-selection{position:absolute;left:0;right:0;border:2px solid var(--pri);background:color-mix(in srgb,var(--pri) 18%,transparent);pointer-events:none}
.mbi-crop-fields{display:flex;gap:12px;margin-top:8px}
.mbi-crop-fields label{display:flex;flex-direction:column;gap:4px;flex:1;min-width:0}
.mbi-crop-fields input{width:100%;min-height:44px}
.mbi-answer-pages{display:flex;flex-direction:column;gap:18px;max-height:60vh;overflow:auto}
.mbi-answer-pages section{padding:16px;background:var(--soft);border-radius:var(--r-sm)}
.mbi-answer-pages h3{margin:0 0 12px;font-size:16px}
.mbi-answer-pages img{max-width:min(100%,480px);max-height:300px;object-fit:contain;background:#fff}
.mbi-answer-row{display:grid;grid-template-columns:100px 100px minmax(0,1fr);gap:10px;margin-top:12px}
.mbi-answer-row label{display:flex;flex-direction:column;gap:5px;font-size:12px;color:var(--muted)}
.mbi-answer-row input,.mbi-answer-row textarea{min-width:0;font:inherit;font-size:14px;color:var(--ink);border:1px solid var(--line2);border-radius:var(--r-xs);padding:8px;background:#fff}
.mbi-answer-row textarea{min-height:72px;resize:vertical}
.mbi :focus-visible,.ro-book-head :focus-visible{outline:2px solid var(--pri);outline-offset:2px}
@media(max-width:700px){.ro-book-head{align-items:flex-start;flex-direction:column}.mbi{padding:16px}.mbi-file b{min-width:100%}.mbi-list,.mbi-answer-pages{max-height:none}.mbi-answer-row{grid-template-columns:1fr 1fr}.mbi-answer-row label:nth-child(3){grid-column:1/-1}.mbi-crop-parts{display:block}.mbi-crop-part+.mbi-crop-part{margin-top:24px}}