:root{color-scheme:light;--bg:#f4f6fb;--surface:#fff;--surface-2:#f8faff;--text:#202b49;--muted:#77819b;--line:#e7eaf3;--primary:#5368d8;--primary-dark:#4053bf;--primary-soft:#edf0ff;--mint:#dff7f0;--mint-strong:#28a888;--yellow:#ffe7a0;--shadow:0 12px 35px rgba(40,55,110,.07);--radius:20px;font-family:'Noto Sans KR',system-ui,-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--text);font-size:14px;line-height:1.55;transition:background .2s,color .2s}body.dark{color-scheme:dark;--bg:#141827;--surface:#1d2335;--surface-2:#222a3f;--text:#edf1ff;--muted:#a0aac6;--line:#343c53;--primary:#91a0ff;--primary-dark:#aeb8ff;--primary-soft:#2c3557;--mint:#1e453f;--mint-strong:#79dec4;--yellow:#4c4326;--shadow:0 12px 35px rgba(0,0,0,.2)}button,input,select,textarea{font:inherit}button{cursor:pointer}button:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible,.rich-editor:focus-visible{outline:3px solid rgba(83,104,216,.25);outline-offset:2px}button:disabled{opacity:.55;cursor:not-allowed}a{color:inherit;text-decoration:none}button:focus:not(:focus-visible){outline:none}[hidden]{display:none!important}.app-shell{max-width:1680px;margin:auto;min-height:100vh}.topbar{height:82px;background:var(--surface);border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 34px;position:sticky;top:0;z-index:20}.brand{display:flex;align-items:center;gap:12px;min-width:250px}.brand-mark{width:42px;height:42px;border-radius:14px;background:linear-gradient(135deg,#5368d8,#8190ff);color:white;display:grid;place-items:center;font-size:25px;font-weight:800;position:relative;box-shadow:0 7px 16px rgba(83,104,216,.25)}.brand-mark i{position:absolute;font-style:normal;font-size:14px;right:-4px;top:-5px;color:#f9c75c;text-shadow:0 1px 3px #fff}.brand-copy{display:flex;flex-direction:column;gap:1px}.brand-copy 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.avatar{width:34px;height:34px;border-radius:50%;background:var(--primary-soft);color:var(--primary);display:grid;place-items:center;font-weight:800}.user-chip strong{display:block;font-size:12px}.user-chip small{display:block;color:var(--muted);font-size:10px}.button{border:1px solid transparent;border-radius:11px;padding:10px 16px;font-size:12px;font-weight:700;display:inline-flex;align-items:center;justify-content:center;gap:7px;line-height:1.3;transition:transform .15s,background .15s,border-color .15s;white-space:nowrap}.button:hover{transform:translateY(-1px)}.button-primary{background:var(--primary);color:white;box-shadow:0 6px 13px rgba(83,104,216,.16)}body.dark 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var(--line);border-radius:10px;background:var(--surface);color:var(--muted);font-size:24px;display:grid;place-items:center;position:absolute;right:18px;top:17px;line-height:1}.modal-kicker{font-size:9px;color:var(--primary);font-weight:800;letter-spacing:1.7px}.modal-panel h2{font-size:21px;letter-spacing:-.6px;margin:5px 0 5px}.modal-intro{font-size:11px;color:var(--muted);line-height:1.7;margin:0 0 18px}.auth-tabs,.admin-tabs{display:flex;gap:5px;background:var(--surface-2);padding:4px;border-radius:11px;margin:19px 0 18px}.auth-tab,.admin-tab{flex:1;border:0;border-radius:8px;padding:9px;background:transparent;color:var(--muted);font-size:12px;font-weight:700}.auth-tab.active,.admin-tab.active{background:var(--surface);color:var(--primary);box-shadow:0 2px 7px rgba(30,40,90,.08)}.form-stack{display:grid;gap:12px}.form-stack label,.compose-label{display:grid;gap:6px;font-size:11px;font-weight:700;color:var(--text)}.form-stack input,.form-stack textarea,.form-stack 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var(--line);background:var(--surface);border-radius:7px;font-size:13px;font-weight:800;cursor:pointer}.color-tool input{position:absolute;inset:0;width:100%;height:100%;opacity:0;cursor:pointer}.highlight-tool{color:#a77e11}.rich-editor{min-height:350px;max-height:55vh;overflow:auto;border:1px solid var(--line);border-radius:0 0 11px 11px;padding:17px;background:var(--surface);font-size:14px;line-height:1.9;overflow-wrap:anywhere;outline:none}.rich-editor:empty:before{content:attr(data-placeholder);color:var(--muted);pointer-events:none}.rich-editor:focus{border-color:#bac4f6}.rich-editor img{max-width:100%;height:auto;cursor:pointer;vertical-align:middle}.rich-editor .math-node{white-space:nowrap;background:var(--primary-soft);border-radius:5px;padding:2px}.rich-editor table{border-collapse:collapse}.rich-editor td,.rich-editor th{border:1px solid var(--line);padding:5px}.image-size-row{display:flex;align-items:center;gap:9px;padding:8px 12px;background:var(--primary-soft);border:1px solid var(--line);border-bottom:0;font-size:10px;color:var(--text)}.image-size-row input{flex:1;min-width:70px;accent-color:var(--primary)}.image-size-row span{white-space:nowrap}.muted-mini{color:var(--muted);font-size:9px}.compose-bottom{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-top:13px}.draft-status{font-size:10px;color:var(--muted)}.compose-buttons{display:flex;align-items:center;gap:8px}.equation-panel{width:min(100%,610px)}.equation-help{font-size:11px;color:var(--muted);line-height:1.7}.equation-panel>.compose-label{margin-top:13px}.equation-slots{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:9px;margin:12px 0}.equation-slot label{display:grid;gap:5px;font-size:10px;color:var(--muted)}.equation-slot input{min-width:0;width:100%;padding:9px;border:1px solid var(--line);border-radius:9px;background:var(--surface-2);color:var(--text)}.equation-preview-label{font-size:10px;color:var(--muted);margin:10px 0 5px}.equation-preview{background:var(--surface-2);border:1px solid var(--line);border-radius:10px;min-height:65px;display:flex;align-items:center;justify-content:center;padding:14px;overflow:auto;font-size:18px}.equation-panel textarea{width:100%;resize:vertical;line-height:1.6}.equation-actions{justify-content:flex-end;margin-top:15px}.material-panel{width:min(100%,540px)}.admin-panel{width:min(100%,760px)}.admin-search{display:flex;gap:8px;margin:12px 0}.admin-search input,.inline-add input{min-width:0;flex:1;padding:10px 12px;border:1px solid var(--line);background:var(--surface-2);color:var(--text);border-radius:10px;font-size:11px}.student-table{max-height:380px;overflow:auto;border:1px solid var(--line);border-radius:10px}.student-row{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:10px;align-items:center;padding:11px 12px;border-bottom:1px solid var(--line)}.student-row:last-child{border-bottom:0}.student-row strong{display:block;font-size:11px}.student-row small{display:block;color:var(--muted);font-size:10px}.student-row .button{font-size:10px;padding:7px 9px}.inline-add{display:flex;gap:8px;margin:13px 0}.admin-category-list{display:grid;gap:8px}.admin-category-row{display:flex;justify-content:space-between;gap:10px;align-items:center;padding:10px 12px;border:1px solid var(--line);border-radius:10px;font-size:11px}.admin-category-row .button{padding:6px 9px;font-size:10px}.toast-region{position:fixed;right:20px;bottom:20px;z-index:100;display:grid;gap:8px;max-width:min(390px,calc(100vw - 40px))}.toast{background:#202943;color:#fff;border-radius:12px;padding:12px 15px;box-shadow:0 8px 24px rgba(0,0,0,.2);font-size:11px;animation:toast-in .2s ease-out}.toast.error{background:#9d3145}.toast.success{background:#176c59}@keyframes toast-in{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}body.dark .welcome-strip{background:linear-gradient(110deg,#2b3356 0%,#252b46 50%,#1c403d 100%);color:#f0f2ff}body.dark .welcome-copy p{color:#bdc6e4}body.dark .question-card:hover{border-color:#505a80}body.dark .notice-panel{border-color:#434c6d}body.dark .button-danger{background:#4b2832;border-color:#683642}body.dark .pill-label.featured{background:#4b3c20;color:#ffdc87}body.dark .pill-label.answered{background:#1f443b;color:#8ce6c3}body.dark .pill-label.teacher{background:#3e2c56;color:#d4b2ff}
@media(max-width:1320px){.layout{grid-template-columns:200px minmax(350px,1fr) 250px;gap:17px;padding:20px}.topbar{padding:0 24px}.right-sidebar{gap:10px}.side-card{padding:15px 13px}.welcome-art{right:15px}.welcome-copy h1{font-size:22px}}
@media(max-width:1080px){.layout{grid-template-columns:190px minmax(0,1fr)}.right-sidebar{position:static;grid-column:2;grid-template-columns:repeat(2,minmax(0,1fr));align-items:start}.points-card{grid-column:1/-1}.rank-list{grid-template-columns:repeat(3,minmax(0,1fr))}.welcome-art{opacity:.45}.left-sidebar{top:100px}}
@media(max-width:720px){.topbar{height:68px;padding:0 15px}.brand{min-width:0;gap:8px}.brand-mark{width:37px;height:37px;border-radius:12px;font-size:22px}.brand-copy strong{font-size:14px}.brand-copy small{font-size:8px;letter-spacing:1px}.connection-badge{display:none}.topbar-actions{gap:8px}.user-area .button{font-size:10px;padding:9px 10px}.user-chip>div:last-child{display:none}.layout{display:flex;flex-direction:column;padding:13px 12px 28px;gap:18px}.left-sidebar{position:static;width:100%;min-height:0;padding:0;display:block;order:0}.sidebar-label,.side-divider,.sidebar-section-heading,.category-list,.left-tip,.sidebar-footer{display:none}.left-sidebar:after{content:'질문 게시판 · 학습자료실에서 과학 탐험을 시작해요';display:block;text-align:center;color:var(--muted);font-size:10px;padding:0 0 4px}.left-sidebar .nav-item{display:inline-flex;width:auto;margin:0 5px 0 0;padding:9px 12px;font-size:11px}.main-content{width:100%;order:1}.right-sidebar{width:100%;order:2;grid-column:auto;display:grid;grid-template-columns:1fr 1fr;gap:10px}.profile-card{grid-column:1/-1}.points-card{grid-column:1/-1}.welcome-strip{min-height:145px;padding:23px 20px;margin-bottom:22px;border-radius:17px}.welcome-copy h1{font-size:20px;max-width:270px}.welcome-copy p{font-size:10px;max-width:250px}.welcome-art{right:-31px;transform:scale(.72);opacity:.35}.page-heading{align-items:flex-start;gap:10px;margin-bottom:16px}.page-heading h2{font-size:20px}.page-heading p{font-size:10px;max-width:240px}.page-heading .button-large{font-size:10px;padding:11px 10px}.board-toolbar{align-items:stretch;flex-direction:column}.search-box{max-width:none;flex:auto}.toolbar-right{justify-content:space-between}.notice-panel{align-items:flex-start;padding:13px;gap:9px}.notice-panel .button{align-self:center;margin-left:0;font-size:10px;padding:8px}.notice-panel p{font-size:10px}.question-head{padding:12px;gap:9px}.question-number{width:31px;height:31px;border-radius:10px}.question-title{font-size:12px}.question-meta{gap:6px;font-size:9px}.question-side{gap:5px}.like-mini{font-size:10px}.question-full{padding:14px 13px}.question-actions .push-right{margin-left:0}.materials-grid{grid-template-columns:1fr}.side-card{padding:14px}.rank-list{grid-template-columns:repeat(2,minmax(0,1fr))}.modal-backdrop{padding:9px}.modal-panel{padding:24px 18px 20px;border-radius:17px;max-height:calc(100vh - 18px)}.compose-panel{padding:21px 13px 15px}.compose-head{padding-right:36px}.compose-head h2{font-size:19px}.field-row{grid-template-columns:1fr}.editor-toolbar{gap:2px;padding:5px}.editor-toolbar button{padding:4px 5px;font-size:10px}.editor-toolbar select{max-width:85px}.tool-separator{margin:0 1px}.rich-editor{min-height:310px;padding:12px;font-size:13px}.compose-bottom{align-items:flex-start;flex-direction:column}.compose-buttons{width:100%;justify-content:flex-end}.draft-status{font-size:9px}.image-size-row{flex-wrap:wrap}.image-size-row input{flex-basis:100%;order:4}.equation-slots{grid-template-columns:1fr 1fr}.student-row{grid-template-columns:minmax(0,1fr) auto}.student-row .button{white-space:normal}.admin-panel{padding:23px 13px}.admin-search{flex-direction:column}.featured-card{grid-column:auto}.profile-empty{padding-top:10px}}
@media(hover:none){.question-card .question-full{display:none}.question-card.is-expanded .question-full{display:block}}

/* Version 2 updates: announcements, notifications, uploads and teacher management */
.notice-banner{background:linear-gradient(110deg,#e9edff 0%,#f5f6ff 55%,#e5faf3 100%);border:1px solid rgba(83,104,216,.16);border-radius:22px;padding:20px 25px;margin-bottom:26px;color:#25335f;box-shadow:0 8px 24px rgba(40,55,110,.04)}
.notice-banner-heading{display:flex;align-items:center;justify-content:space-between;gap:12px;margin-bottom:8px}.notice-title-label{font-size:12px;font-weight:850;letter-spacing:.5px;color:#5368d8}.notice-controls{display:flex;align-items:center;gap:8px}.notice-controls .button{padding:6px 10px;font-size:11px}.notice-content h1{font-size:22px;line-height:1.4;letter-spacing:-.6px;margin:9px 0}.notice-content p{font-size:13px;color:#53617f;line-height:1.8;white-space:pre-wrap;overflow-wrap:anywhere;margin:0}.notice-content small{display:block;margin-top:10px;font-size:10px;color:#7a86a2}
.notification-wrap{position:relative}.notification-button{position:relative}.notification-badge{position:absolute;top:-5px;right:-5px;min-width:18px;height:18px;border-radius:99px;background:#e44d72;color:#fff;font-size:10px;line-height:18px;font-weight:800;text-align:center;padding:0 4px;border:2px solid var(--surface)}.notifications-panel{position:absolute;top:48px;right:-42px;width:min(360px,calc(100vw - 30px));max-height:min(480px,70vh);overflow:auto;padding:13px;background:var(--surface);color:var(--text);border:1px solid var(--line);border-radius:16px;box-shadow:0 16px 44px rgba(27,36,78,.2);z-index:90}.notifications-heading{display:flex;align-items:center;justify-content:space-between;padding:2px 2px 10px;border-bottom:1px solid var(--line);margin-bottom:6px}.notification-item{display:flex;width:100%;flex-direction:column;gap:4px;text-align:left;padding:11px 10px;border:0;border-radius:10px;background:transparent;color:var(--text);border-bottom:1px solid var(--line)}.notification-item:hover,.notification-item.unread{background:var(--primary-soft)}.notification-item strong{font-size:12px}.notification-item span{font-size:11px;color:var(--muted);line-height:1.5}.notification-item small{font-size:10px;color:var(--muted)}
.compose-message{margin:10px 0 0;font-size:12px;white-space:pre-wrap}.compose-message.error{color:#d64c5e}.compose-message.success{color:#23866a}
.selected-material-files{display:grid;gap:5px;padding:2px 0}.selected-material-file{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:8px 10px;border:1px solid var(--line);border-radius:9px;background:var(--surface-2);font-size:11px}.selected-file-name{min-width:0;overflow-wrap:anywhere}.selected-file-name small{display:inline-block;color:var(--muted);margin-left:5px}.danger-text{color:#d64c5e!important;flex-shrink:0}.student-row-actions{display:flex;gap:6px;flex-wrap:wrap;justify-content:flex-end}.student-row-actions .button{padding:7px 9px;font-size:10px}.category-order-buttons{display:flex;gap:4px}.category-order-buttons .tiny-icon{min-width:25px;height:25px}.admin-category-name{flex:1;min-width:0;overflow-wrap:anywhere}.notice-edit-panel{width:min(640px,calc(100vw - 28px))}.notice-edit-panel textarea{resize:vertical;min-height:140px}
@media(max-width:850px){.notice-banner{padding:17px 18px}.notice-content h1{font-size:19px}.notifications-panel{right:-75px}.student-row-actions{justify-content:flex-start}}


/* Version 3 updates: stable document numbers, date search and material preview */
.date-filter-row{display:flex;align-items:end;gap:8px;flex-wrap:wrap;margin:10px 0 17px;padding:11px 13px;border:1px solid var(--line);border-radius:12px;background:var(--surface)}
.date-filter-row label{display:flex;align-items:center;gap:7px;font-size:10px;font-weight:700;color:var(--muted)}
.date-filter-row input{min-width:135px;padding:8px 9px;border:1px solid var(--line);border-radius:8px;background:var(--surface-2);color:var(--text);font:inherit}
.date-filter-row .button{font-size:10px;padding:8px 11px}
.date-range-separator{font-size:12px;color:var(--muted);padding-bottom:8px}
.date-filter-message{font-size:10px;color:#d95567;flex-basis:100%;min-height:0}
.question-number{width:auto;min-width:64px;height:36px;padding:0 7px;border-radius:10px;white-space:nowrap;font-size:10px;font-variant-numeric:tabular-nums}
.rank-dot.king{background:#e1a52b;box-shadow:0 0 0 3px rgba(225,165,43,.15)}
.teacher-rank-note{font-size:10px;color:var(--muted);margin:8px 0 0}
.material-preview-panel{width:min(1100px,calc(100vw - 36px));height:min(90vh,900px);display:flex;flex-direction:column;gap:10px}
.material-preview-body{flex:1;min-height:180px;overflow:auto;border:1px solid var(--line);border-radius:12px;background:var(--surface-2);padding:10px;display:flex;flex-direction:column;align-items:stretch}
.material-preview-frame{width:100%;height:100%;min-height:60vh;border:0;background:white;border-radius:8px}
.material-preview-image{display:block;max-width:100%;max-height:66vh;object-fit:contain;margin:auto}
.material-preview-media{width:100%;max-height:65vh;margin:auto}
.material-text-preview{white-space:pre-wrap;overflow-wrap:anywhere;max-height:65vh;overflow:auto;font:12px/1.65 ui-monospace,SFMono-Regular,Menlo,monospace;color:var(--text);background:var(--surface);padding:15px;border-radius:8px;margin:0}
.material-docx-preview{background:var(--surface);color:var(--text);padding:22px;line-height:1.8;border-radius:8px;overflow-wrap:anywhere}
.material-docx-preview img{max-width:100%;height:auto}
.material-docx-preview table,.material-spreadsheet{border-collapse:collapse;max-width:100%;background:var(--surface);font-size:11px}
.material-docx-preview td,.material-docx-preview th,.material-spreadsheet td,.material-spreadsheet th{border:1px solid var(--line);padding:6px 8px;vertical-align:top}
.material-spreadsheet{width:100%;white-space:pre-wrap}.spreadsheet-preview-tabs{display:flex;gap:6px;overflow:auto;margin-bottom:10px}.spreadsheet-preview-tabs .button{flex-shrink:0;font-size:10px;padding:7px 10px}.spreadsheet-preview-content{overflow:auto;max-height:62vh}
.pptx-preview-host{width:100%;overflow:auto;background:var(--surface);border-radius:8px;padding:12px}.pptx-preview-host>*{max-width:100%}
.preview-loading,.preview-fallback{margin:auto;text-align:center;color:var(--muted);padding:28px;max-width:600px;line-height:1.8}.preview-fallback-icon{font-size:40px;margin-bottom:12px}.preview-fallback strong{display:block;color:var(--text);font-size:14px;margin-bottom:8px}.preview-fallback p{font-size:12px;overflow-wrap:anywhere}
.material-preview-footer{display:flex;align-items:center;justify-content:space-between;gap:12px}.material-preview-footer .form-note{margin:0;max-width:65%}
@media(max-width:720px){.date-filter-row{align-items:stretch}.date-filter-row label{flex:1;min-width:100%;justify-content:space-between}.date-filter-row input{min-width:0;max-width:60%}.date-range-separator{display:none}.material-preview-panel{width:calc(100vw - 18px);height:calc(100vh - 18px);padding:20px 12px}.material-preview-footer{align-items:flex-start;flex-direction:column}.material-preview-footer .form-note{max-width:100%}.question-number{min-width:59px;padding:0 5px;font-size:9px}}
body.dark .material-preview-body{background:var(--surface-2)}

.material-doc-structure-preview{display:grid;gap:14px}.document-section-preview{background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:17px}.document-section-preview h3{font-size:12px;color:var(--primary);margin:0 0 10px}.document-section-text{white-space:pre-wrap;overflow-wrap:anywhere;font-size:12px;line-height:1.8;color:var(--text);min-height:24px}


/* v4 interactive equation editor */
.equation-panel{width:min(100%,920px)}
.equation-category-tabs{display:flex;gap:6px;flex-wrap:wrap;margin:14px 0 10px;padding-bottom:3px}
.equation-category-tab{border:1px solid var(--line);background:var(--surface-2);color:var(--text);border-radius:9px;padding:8px 11px;font-size:11px;font-weight:750;cursor:pointer}
.equation-category-tab.active,.equation-category-tab:hover{background:var(--primary-soft);border-color:var(--primary);color:var(--primary)}
.equation-template-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:8px;max-height:190px;overflow:auto;padding:2px 2px 9px}
.equation-template-card{min-width:0;min-height:77px;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:9px;padding:8px;border:1px solid var(--line);border-radius:10px;background:var(--surface);color:var(--text);cursor:pointer;transition:border-color .15s,background .15s}
.equation-template-card:hover,.equation-template-card.selected{border-color:var(--primary);background:var(--primary-soft)}
.equation-template-preview{min-height:34px;display:flex;align-items:center;justify-content:center;max-width:100%;overflow:hidden;font-size:20px;line-height:1.3}
.equation-template-name{font-size:10px;color:var(--muted);text-align:center;line-height:1.35}
.math-entry-heading,.symbol-toolbar-heading{display:flex;justify-content:space-between;align-items:baseline;gap:12px;margin:13px 0 7px;font-size:11px;color:var(--text)}
.math-entry-heading span,.symbol-toolbar-heading span{font-size:9px;color:var(--muted);font-weight:400}
.equation-mathfield{box-sizing:border-box;display:block;width:100%;min-height:74px;padding:13px;border:1px solid var(--line);border-radius:11px;background:var(--surface);color:var(--text);font-size:25px;--hue:235;--contains-highlight-background-color:rgba(91,109,220,.16);--placeholder-color:var(--primary);--placeholder-opacity:1}
.equation-mathfield:focus{outline:2px solid rgba(88,105,220,.25);border-color:var(--primary)}
.math-live-actions{display:flex;justify-content:flex-end;gap:6px;margin-top:6px}
.math-live-actions .button{font-size:10px;padding:7px 10px}
.symbol-toolbar{display:flex;align-items:stretch;gap:4px;flex-wrap:wrap;padding:5px;border:1px solid var(--line);border-radius:10px;background:var(--surface-2);overflow:visible}
.symbol-group{position:relative;display:flex;align-self:stretch;min-height:39px;border:1px solid var(--line);border-radius:7px;background:var(--surface);color:var(--text)}
.symbol-main,.symbol-caret{border:0;background:transparent;color:inherit;cursor:pointer;min-width:29px;padding:5px 7px;font-size:18px;line-height:1.2}
.symbol-main:hover,.symbol-caret:hover{background:var(--primary-soft);color:var(--primary)}
.symbol-caret{min-width:17px;padding:5px 4px;font-size:10px;color:var(--muted)}
.symbol-menu{position:absolute;left:0;top:calc(100% + 4px);z-index:30;width:min(284px,80vw);max-height:210px;overflow:auto;padding:7px;display:grid;grid-template-columns:repeat(6,minmax(0,1fr));gap:4px;border:1px solid var(--line);border-radius:10px;background:var(--surface);box-shadow:0 8px 28px rgba(20,30,65,.17)}
.symbol-menu[hidden]{display:none}
.symbol-menu-item{min-width:0;min-height:34px;border:1px solid transparent;border-radius:6px;background:var(--surface-2);color:var(--text);font-size:14px;cursor:pointer;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.symbol-menu-item:hover{border-color:var(--primary);background:var(--primary-soft);color:var(--primary)}
.latex-details{margin-top:10px;border:1px solid var(--line);border-radius:9px;padding:9px 11px}
.latex-details summary{cursor:pointer;font-size:10px;color:var(--muted);font-weight:700}
.latex-details .compose-label{margin-top:10px}
.latex-details textarea{width:100%;margin-top:7px;border:1px solid var(--line);border-radius:8px;padding:9px;background:var(--surface-2);color:var(--text);font:12px/1.6 ui-monospace,SFMono-Regular,Menlo,monospace}
.equation-preview{margin-top:5px;min-height:56px}
@media(max-width:720px){.equation-template-grid{grid-template-columns:repeat(2,minmax(0,1fr));max-height:170px}.equation-template-card{min-height:69px}.equation-template-preview{font-size:17px}.equation-mathfield{font-size:21px;min-height:68px}.math-entry-heading,.symbol-toolbar-heading{align-items:flex-start;flex-direction:column;gap:3px}.symbol-menu{grid-template-columns:repeat(5,minmax(0,1fr))}.equation-category-tab{padding:7px 8px;font-size:10px}}