/* 참조 시트 오버레이 공용 스타일 — 단일 정본.
   UI_bluebook(base_exam.html)과 UI_basic(exam/base_exam.html) 이 함께 링크한다.
   마크업: templates/exam/partials/_reference_sheet.html
   내용 판정: quiz/services/reference_sheets.py */

/* 오버레이 공용 껍데기 (Desmos 오버레이도 같이 쓴다) */
.bb-tool-overlay { display:none; position:fixed; top:64px; right:20px; background:#fff; border:1.5px solid #e5e7eb; border-radius:12px; z-index:400; box-shadow:0 8px 32px rgba(0,0,0,.14); overflow:hidden; }
.bb-tool-overlay.show { display:flex; flex-direction:column; }
.bb-tool-overlay.desmos-overlay { width:640px; height:520px; }
.bb-tool-overlay.ref-overlay { width:440px; }
.bb-tool-overlay.ref-overlay-wide { width:min(760px, calc(100vw - 40px)); }
.bb-overlay-header { background:#f9fafb; border-bottom:1px solid #e5e7eb; padding:10px 14px; display:flex; align-items:center; justify-content:space-between; font-size:13px; font-weight:600; color:#374151; cursor:move; flex-shrink:0; user-select:none; }
.bb-overlay-close { background:none; border:none; cursor:pointer; color:#9ca3af; font-size:16px; width:24px; height:24px; display:flex; align-items:center; justify-content:center; border-radius:4px; transition:background .1s,color .1s; }
.bb-overlay-close:hover { background:#f3f4f6; color:#374151; }

/* 시트 본문 */
.bb-ref-content { padding:14px 16px; overflow-y:auto; max-height:calc(100vh - 160px); }
.ref-section { margin-bottom:14px; }
.ref-section h3 { font-size:10.5px; font-weight:700; text-transform:uppercase; letter-spacing:.08em; color:#6b7280; margin-bottom:6px; border-bottom:1px solid #e5e7eb; padding-bottom:3px; margin-top:0; }
.ref-grid { display:grid; grid-template-columns:1fr 1fr; gap:5px; }
.ref-formula { background:#f9fafb; border:1px solid #e5e7eb; border-radius:5px; padding:6px 8px; font-size:12.5px; }
.ref-formula strong { display:block; color:#374151; font-size:10.5px; margin-bottom:2px; }
.ref-note { font-size:11px; color:#9ca3af; margin-top:10px; border-top:1px solid #e5e7eb; padding-top:8px; }
.ref-note-top { margin-top:0; border-top:none; padding-top:0; margin-bottom:10px; }

/* 시트가 둘 이상일 때의 탭 */
.ref-tabs { display:flex; gap:2px; padding:8px 12px 0; border-bottom:1px solid #e5e7eb; flex-shrink:0; }
.ref-tab { background:none; border:none; border-bottom:2px solid transparent; padding:6px 12px 8px; font-size:12.5px; font-weight:600; color:#6b7280; cursor:pointer; }
.ref-tab:hover { color:#374151; }
.ref-tab.is-active { color:#0f766e; border-bottom-color:#0f766e; }
.ref-pane { display:none; }
.ref-pane.is-active { display:block; }

/* 원본 스캔 페이지 (적분표) */
.ref-page-img { display:block; width:100%; height:auto; border:1px solid #e5e7eb; border-radius:6px; margin-bottom:12px; background:#fff; }