:root{
--bg:#f3f3f1;--surface:#fff;--surface-2:#f8f8f6;--ink:#171817;--muted:#747773;--line:#dedfdb;--line-strong:#c8cac5;--accent:#20221f;--shadow:0 12px 38px rgba(20,22,18,.07);--radius:18px;
--sans:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;
}
*{box-sizing:border-box}html,body{margin:0;min-height:100%;font-family:var(--sans);color:var(--ink);background:var(--bg)}
button,input,select,textarea{font:inherit}button{cursor:pointer}
.app-shell{display:flex;min-height:100vh}.sidebar{position:fixed;inset:0 auto 0 0;width:258px;background:#ecece9;border-right:1px solid var(--line);padding:28px 18px;display:flex;flex-direction:column}
.brand{display:flex;align-items:center;gap:11px;padding:0 9px 30px}.brand-mark{display:grid;place-items:center;width:34px;height:34px;border-radius:10px;background:var(--ink);color:#fff;font-weight:800;font-size:20px}.brand strong{display:block;font-size:15px;letter-spacing:-.02em}.brand small{display:block;color:var(--muted);font-size:10px;margin-top:2px;letter-spacing:.03em}
.school-switch{border:1px solid var(--line);background:rgba(255,255,255,.56);border-radius:13px;padding:13px 14px;margin-bottom:24px}.eyebrow,.nav-label{font-size:10px;letter-spacing:.12em;text-transform:uppercase;color:#92948f}.school-switch strong{display:block;font-size:12px;margin:6px 0 3px}.muted{font-size:11px;color:var(--muted)}
nav{display:flex;flex-direction:column;gap:4px}.nav-label{margin:5px 10px 7px}.nav-label:not(:first-child){margin-top:22px}.nav-item{border:0;background:transparent;text-align:left;padding:11px 12px;border-radius:10px;color:#626560;display:flex;align-items:center;gap:12px;font-size:13px;transition:.18s}.nav-item span{font-size:9px;color:#a0a29d;width:16px}.nav-item:hover{background:rgba(255,255,255,.62);color:var(--ink)}.nav-item.active{background:var(--ink);color:#fff;box-shadow:0 5px 16px rgba(0,0,0,.12)}.nav-item.active span{color:#aaa}
.sidebar-bottom{margin-top:auto;border-top:1px solid var(--line);padding:17px 8px 0;display:flex;gap:9px;align-items:center}.sidebar-bottom strong{font-size:11px;display:block}.sidebar-bottom small{font-size:10px;color:var(--muted)}.sync-dot{width:7px;height:7px;border-radius:50%;background:#4b514b}
.main{margin-left:258px;width:calc(100% - 258px);padding:0 44px 56px}.topbar{height:105px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.breadcrumb{font-size:11px;color:var(--muted)}.topbar h1{font-size:24px;letter-spacing:-.035em;margin:7px 0 0}.top-actions{display:flex;gap:9px;align-items:center}.ghost-btn,.profile{border:1px solid var(--line-strong);background:var(--surface);padding:9px 13px;border-radius:10px;font-size:12px}.profile{display:flex;gap:10px;align-items:center}.profile span{display:grid;place-items:center;width:25px;height:25px;border-radius:7px;background:#e9eae7;font-size:9px;font-weight:700}
#content{padding-top:28px;max-width:1400px}.view-head{display:flex;justify-content:space-between;align-items:end;margin-bottom:20px}.view-head h2{font-size:17px;margin:0;letter-spacing:-.02em}.view-head p{margin:5px 0 0;color:var(--muted);font-size:12px}.actions{display:flex;gap:8px}.primary{border:1px solid var(--ink);background:var(--ink);color:#fff;border-radius:9px;padding:9px 14px;font-size:12px}.secondary{border:1px solid var(--line-strong);background:var(--surface);border-radius:9px;padding:9px 14px;font-size:12px}
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}.stat,.panel,.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}.stat{padding:18px 19px}.stat-top{display:flex;justify-content:space-between;color:var(--muted);font-size:11px}.stat-value{font-size:29px;font-weight:650;letter-spacing:-.05em;margin:14px 0 4px}.stat-note{font-size:10px;color:var(--muted)}
.grid-2{display:grid;grid-template-columns:1.35fr .65fr;gap:14px;margin-top:14px}.panel{padding:19px}.panel-title{display:flex;align-items:center;justify-content:space-between;margin-bottom:16px}.panel-title h3{font-size:13px;margin:0}.panel-title a{font-size:10px;color:var(--muted);text-decoration:none}
.activity{display:flex;flex-direction:column}.activity-row{display:grid;grid-template-columns:65px 1fr 80px;gap:12px;padding:13px 0;border-top:1px solid #ecece9;align-items:center}.activity-row:first-child{border-top:0}.date{font-size:10px;color:var(--muted)}.activity-row strong{font-size:12px}.activity-row small{display:block;color:var(--muted);font-size:10px;margin-top:4px}.score{font-size:13px;text-align:right;font-weight:650}
.mini-bars{display:flex;align-items:end;height:130px;gap:10px;padding:10px 3px 0}.bar-wrap{flex:1;text-align:center;height:100%;display:flex;flex-direction:column;justify-content:end;gap:7px}.bar{background:#252824;border-radius:5px 5px 2px 2px;min-height:8px}.bar-label{font-size:9px;color:var(--muted)}
.table-wrap{overflow:auto;border:1px solid var(--line);border-radius:13px;background:var(--surface)}table{width:100%;border-collapse:collapse;min-width:760px}th,td{padding:13px 14px;text-align:left;border-bottom:1px solid #ecece9;font-size:11px}th{background:#f8f8f6;color:#7b7e78;font-weight:500;font-size:10px}tr:last-child td{border-bottom:0}.tag{display:inline-flex;border:1px solid var(--line);border-radius:999px;padding:4px 8px;font-size:9px;background:#fafaf8}.status{font-size:10px}.status.live{font-weight:700}.status.done{color:var(--muted)}
.exam-layout{display:grid;grid-template-columns:minmax(0,1fr) 355px;gap:14px;height:calc(100vh - 165px);min-height:650px}.reader,.answer-sheet{background:var(--surface);border:1px solid var(--line);border-radius:18px;overflow:hidden;box-shadow:var(--shadow)}.reader-head,.sheet-head{height:57px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 16px}.reader-head strong,.sheet-head strong{font-size:12px}.reader-tools{display:flex;gap:5px}.tool{width:31px;height:30px;border:1px solid var(--line);background:#fff;border-radius:8px;font-size:11px}.paper{height:calc(100% - 57px);overflow:auto;padding:48px 8%;background:#f4f4f2}.paper-page{background:#fff;min-height:980px;max-width:820px;margin:auto;padding:55px 65px;box-shadow:0 12px 30px rgba(0,0,0,.06)}.paper-page h2{font-size:20px;margin:0 0 12px}.paper-page .q{margin-top:32px;font-size:13px;line-height:2}.paper-page .option{margin:5px 0;color:#42443f}.annotation{border-bottom:2px solid #555;padding-bottom:1px}.answer-sheet{display:flex;flex-direction:column}.sheet-body{overflow:auto;padding:14px}.timer{font-variant-numeric:tabular-nums;font-size:14px;font-weight:700}.save-state{font-size:9px;color:var(--muted);padding:8px 12px;background:#f7f7f5;border-radius:8px;margin-bottom:10px}.answer-row{border:1px solid var(--line);border-radius:11px;padding:12px;margin-bottom:8px}.answer-row.is-active{border-color:#6d706b;box-shadow:0 0 0 2px #eeeeeb}.answer-row-head{display:flex;justify-content:space-between;font-size:11px;margin-bottom:9px}.choices{display:grid;grid-template-columns:repeat(4,1fr);gap:5px}.choice{border:1px solid var(--line);background:#fafaf8;border-radius:7px;padding:7px 0;text-align:center;font-size:10px}.choice.selected{background:var(--ink);border-color:var(--ink);color:#fff}.submit-bar{margin-top:auto;border-top:1px solid var(--line);padding:13px 14px}.submit-bar button{width:100%}
.question-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.question-card{padding:17px}.question-card h3{font-size:13px;margin:12px 0 7px}.question-card p{font-size:10px;line-height:1.7;color:var(--muted);margin:0}.meta{display:flex;gap:6px;flex-wrap:wrap}.difficulty{font-size:10px;font-weight:700}
.version-list{display:grid;gap:9px}.version{border:1px solid var(--line);border-radius:12px;padding:15px;display:flex;justify-content:space-between;align-items:center;background:#fff}.version.current{border-color:#666a65;box-shadow:0 0 0 2px #ededeb}.version strong{font-size:12px}.version small{display:block;color:var(--muted);font-size:10px;margin-top:4px}.version .mark{font-size:9px;border:1px solid var(--line);border-radius:999px;padding:4px 7px}
.discussion{display:grid;grid-template-columns:1fr 310px;gap:14px}.comment{padding:15px 0;border-bottom:1px solid #ecece9}.comment:last-child{border:0}.comment-head{display:flex;justify-content:space-between;font-size:11px}.comment small{color:var(--muted)}.comment p{font-size:11px;line-height:1.7;margin:9px 0 0}.moderation{color:#6f716d;font-size:10px}
.profile-card{display:grid;grid-template-columns:110px 1fr;gap:20px;padding:22px}.avatar-lg{width:90px;height:90px;border-radius:22px;background:#242622;color:#fff;display:grid;place-items:center;font-size:27px;font-weight:700}.detail-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.detail{border-top:1px solid var(--line);padding-top:10px}.detail span{display:block;color:var(--muted);font-size:9px;margin-bottom:5px}.detail strong{font-size:12px}
.empty{padding:45px;text-align:center;color:var(--muted);font-size:12px}
@media(max-width:1050px){.sidebar{width:220px}.main{margin-left:220px;width:calc(100% - 220px);padding:0 24px}.stats{grid-template-columns:repeat(2,1fr)}.question-grid{grid-template-columns:repeat(2,1fr)}.exam-layout{grid-template-columns:1fr}.answer-sheet{min-height:520px}.discussion,.grid-2{grid-template-columns:1fr}}
@media(max-width:720px){.sidebar{position:static;width:100%;height:auto}.app-shell{display:block}.sidebar nav,.school-switch,.sidebar-bottom{display:none}.brand{padding-bottom:16px}.main{margin:0;width:100%;padding:0 14px}.topbar{height:85px}.topbar h1{font-size:18px}.stats,.question-grid{grid-template-columns:1fr}.top-actions .ghost-btn{display:none}.profile{padding:5px 8px}.exam-layout{height:auto}.paper{padding:20px}.paper-page{padding:30px 22px}.choices{grid-template-columns:repeat(2,1fr)}}


.empty{padding:34px;text-align:center;color:var(--muted);font-size:12px}
.real-question{padding:22px 0;border-bottom:1px solid var(--line)}
.real-question:last-child{border-bottom:0}
.real-question .q-no{font-size:11px;color:var(--muted);letter-spacing:.04em;margin-bottom:9px}
.real-question h3{font-size:15px;line-height:1.9;font-weight:600;margin:0 0 10px;white-space:pre-wrap}
.real-question>.muted{font-size:11px;margin-top:14px}

.form-panel{max-width:980px}
.form-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}
.form-grid label{display:flex;flex-direction:column;gap:8px;font-size:12px;font-weight:650;color:#3d403c}
.form-grid label.full{grid-column:1/-1}
.form-grid input,.form-grid select{width:100%;box-sizing:border-box;border:1px solid #d9dbd6;background:#fbfbf9;border-radius:10px;padding:12px 13px;font:inherit;color:#242724;outline:none}
.form-grid input:focus,.form-grid select:focus{border-color:#a9ada6;box-shadow:0 0 0 3px rgba(60,64,60,.06)}
.form-actions{display:flex;justify-content:flex-end;margin-top:22px;padding-top:18px;border-top:1px solid #ecece8}
.document-wrap{height:min(76vh,900px);min-height:560px;background:#ecece8;border:1px solid #dfe0dc;border-radius:12px;overflow:auto}
.document-frame{width:100%;height:100%;border:0;background:#fff}
.document-empty{height:100%;min-height:560px;display:flex;align-items:center;justify-content:center;flex-direction:column;gap:8px;color:#747871;background:#f7f7f4}
.document-empty strong{font-size:14px;color:#444843}
.document-empty span{font-size:12px}
.live-tag{font-variant-numeric:tabular-nums}
.answer-row.has-answer{background:#fafaf7}
.answer-row .choice:disabled{cursor:not-allowed;opacity:.58}
@media(max-width:900px){.form-grid{grid-template-columns:1fr}.form-grid label.full{grid-column:auto}.document-wrap{min-height:420px;height:62vh}}

.auth-shell{min-height:100vh;display:grid;place-items:center;padding:40px 18px;background:var(--bg)}
.auth-card{width:min(460px,100%);background:#fff;border:1px solid var(--line);border-radius:24px;box-shadow:var(--shadow);padding:30px}
.auth-brand{position:fixed;top:28px;left:32px;display:flex;align-items:center;gap:10px}.auth-brand strong{display:block;font-size:15px}.auth-brand span{display:block;color:var(--muted);font-size:10px;margin-top:3px}
.auth-copy .eyebrow{font-size:9px;letter-spacing:.14em}.auth-copy h1{font-size:25px;letter-spacing:-.04em;margin:8px 0}.auth-copy p{color:var(--muted);font-size:12px;line-height:1.7;margin-bottom:24px}
.auth-tabs{display:grid;grid-template-columns:1fr 1fr;background:#f5f5f2;padding:4px;border-radius:10px;margin-bottom:18px}.auth-tab{border:0;background:transparent;border-radius:7px;padding:9px;font-size:12px;color:var(--muted)}.auth-tab.active{background:#fff;color:var(--ink);box-shadow:0 2px 8px rgba(0,0,0,.05)}
.auth-form{display:grid;gap:12px}.auth-form label,.standalone-field{display:grid;gap:7px;font-size:11px;font-weight:650;color:#40433f}.auth-form input,.auth-form select,.standalone-field input,.auth-form textarea{width:100%;border:1px solid var(--line);background:#fbfbf9;border-radius:9px;padding:11px 12px;outline:none}.auth-form input:focus,.auth-form select:focus,.standalone-field input:focus{border-color:#a9ada6}.wide{width:100%;margin-top:4px}.form-error{min-height:16px;color:#555;font-size:10px}.field-help{font-size:9px;color:var(--muted);font-weight:400}.full textarea{resize:vertical;line-height:1.65}
.auth-base{position:fixed;bottom:25px;display:flex;gap:8px;align-items:center;background:rgba(255,255,255,.78);border:1px solid var(--line);border-radius:11px;padding:7px}.auth-base span{font-size:9px;color:var(--muted)}.auth-base input{width:min(330px,45vw);border:0;background:transparent;outline:0;font-size:10px}
@media(max-width:720px){.auth-brand{position:static;margin-bottom:25px}.auth-shell{display:block;padding:25px 14px}.auth-base{position:static;margin:14px auto 0;width:max-content;max-width:100%}.auth-base input{width:170px}}

.import-preview{margin-top:18px;border:1px dashed var(--line-strong);border-radius:12px;background:#fafaf8;padding:16px;display:grid;gap:8px;font-size:11px;color:var(--muted)}
.import-preview strong{color:var(--ink);font-size:12px}.import-preview span{font-size:10px}.import-preview code{display:block;white-space:pre-wrap;max-height:220px;overflow:auto;background:#f1f1ee;border-radius:9px;padding:12px;font-size:9px;color:#50534e}
.field-label{font-size:11px;font-weight:650;margin-bottom:9px}.check-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}.check-item{display:flex;align-items:center;gap:7px;border:1px solid var(--line);border-radius:9px;padding:10px 11px;background:#fbfbf9;font-size:11px;font-weight:500}.check-item input{accent-color:#20221f}@media(max-width:900px){.check-grid{grid-template-columns:1fr 1fr}}@media(max-width:600px){.check-grid{grid-template-columns:1fr}}
.profile-summary{font-size:14px;line-height:1.85;color:#2e312e}.ai-list{margin:0;padding-left:20px;color:#3f423e;font-size:12px;line-height:2}.version-list{display:grid;gap:7px}.version{display:flex;justify-content:space-between;align-items:center;border:1px solid var(--line);border-radius:10px;padding:11px 13px;background:#fbfbf9}.version.current{border-color:#b6b9b3;background:#f5f5f2}.version small{display:block;color:var(--muted);font-size:9px;margin-top:3px}.mark{font-size:10px;color:var(--muted)}.generated-q{padding:18px 0;border-top:1px solid var(--line)}.generated-q:first-of-type{border-top:0}.generated-q h3{font-size:15px;line-height:1.65;margin:7px 0 12px}.option-grid{display:grid;grid-template-columns:1fr 1fr;gap:7px}.option-grid>div{border:1px solid var(--line);border-radius:8px;padding:9px;font-size:11px;background:#fafaf8}.generated-answer{margin-top:11px;font-size:10px;color:var(--muted);line-height:1.7}@media(max-width:600px){.option-grid{grid-template-columns:1fr}}