/* v7增量显示层。手机纵向保持v6；学生端按CSS可用空间扩展，不识别品牌。
   教师端仍保留原布局。最终回退为容器内滚动，禁止以隐藏题干换空间。 */
body[data-portal="student"]{--v7-page:1120px}
body[data-portal="student"] .review-question>*,body[data-portal="student"] .quiz-card>*,body[data-portal="student"] .word-panel>*{min-width:0}
body[data-portal="student"] .review-sentence{overflow-wrap:anywhere}
body[data-portal="student"] .modal .btn{white-space:normal}
body[data-portal="student"] .v6-answer-dock{width:100%}
@media(min-width:700px){
 body[data-portal="student"]{max-width:1200px;box-shadow:0 0 0 1px #dfe6d9;background:#f6f8f2}
 body[data-portal="student"].review-theme{background:#f3f8f8}
 body[data-portal="student"] .topbar{padding:0 30px;height:72px;max-width:1120px}
 body[data-portal="student"] .main{max-width:1040px;padding:0 30px;margin:25px auto 40px}
 body[data-portal="student"] .page-header h1{font-size:32px}
 body[data-portal="student"] .landing{max-width:1000px;display:grid;grid-template-columns:1fr 1fr;align-items:center;gap:36px;padding:36px 30px}
 body[data-portal="student"] .landing-copy h1{font-size:40px;line-height:1.45}
 body[data-portal="student"] .landing-copy h1 br{display:block}
 body[data-portal="student"] .landing-copy>p{display:block;font-size:15px;line-height:1.9;margin-top:16px}
 body[data-portal="student"] .login-card{padding:30px}
 body[data-portal="student"] .children-grid,body[data-portal="student"] .enrollment-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
 body[data-portal="student"] .v4-welcome{padding:28px 30px}
 body[data-portal="student"] .v4-welcome h2{font-size:34px;line-height:1.5}
 body[data-portal="student"] .v4-course{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 20px}
 body[data-portal="student"] .v4-course>.row,body[data-portal="student"] .v4-course>p{grid-column:1/-1}
 body[data-portal="student"] .v4-task{display:flex;flex-direction:column;padding:25px}
 body[data-portal="student"] .v4-task>.btn{margin-top:auto}
 body[data-portal="student"] .v4-upcoming{grid-template-columns:repeat(2,minmax(0,1fr))}
 body[data-portal="student"] .review-intro{max-width:760px;margin:0 auto;padding:32px}
 body[data-portal="student"] .review-intro h2{font-size:30px}
 body[data-portal="student"] .review-steps{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
 body[data-portal="student"] .review-steps li{padding:40px 0 4px}
 body[data-portal="student"] .review-steps b{font-size:16px}
 body[data-portal="student"] .modal{max-width:680px!important;border-radius:24px;padding:28px;max-height:calc(var(--visual-height,100dvh) - 40px)}
 body[data-portal="student"] .modal-backdrop{align-items:center;padding:20px}
 body[data-portal="student"] #toast{max-width:min(calc(100vw - 48px),620px)}
 body[data-portal="student"] .footer{max-width:1040px;display:flex;justify-content:space-between}
 body[data-portal="student"][data-view="review"] .review-shell{width:min(100%,760px);max-width:760px;padding:18px 24px;gap:12px}
 body[data-portal="student"][data-view="review"] .review-heading h1{font-size:24px}
 body[data-portal="student"][data-view="review"] .review-heading>p:last-child{font-size:13px}
 body[data-portal="student"][data-view="review"] .review-question{padding:24px!important;gap:16px}
 body[data-portal="student"][data-view="review"] .v6-prompt{min-height:110px}
 body[data-portal="student"][data-view="review"] .v6-meaning{font-size:36px}
 body[data-portal="student"][data-view="review"] .review-options{grid-template-columns:repeat(2,minmax(0,1fr));grid-template-rows:repeat(2,minmax(64px,1fr));gap:12px!important;min-height:160px;max-height:320px}
 body[data-portal="student"][data-view="review"] .review-option{font-size:22px;min-height:64px!important;padding:15px!important;flex-wrap:wrap}
 body[data-portal="student"][data-view="review"] .review-option small{margin-left:auto}
 body[data-portal="student"][data-view="review"] .review-listen{min-height:100px}
 body[data-portal="student"][data-view="review"] .review-listen span{font-size:24px}
 body[data-portal="student"][data-view="review"] .review-listen svg{width:36px;height:36px}
 body[data-portal="student"][data-view="review"] .review-sentence{font-size:29px;line-height:1.6}
 body[data-portal="student"][data-view="review"] .review-translation{font-size:16px}
 body[data-portal="student"][data-view="review"] .review-feedback{padding:14px 16px}
 body[data-portal="student"][data-view="review"] .review-feedback p{font-size:16px}
 body[data-portal="student"][data-view="review"] .review-feedback b{font-size:16px}
 body[data-portal="student"][data-view="review"] .review-feedback .v6-choice-note{font-size:13px}
 body[data-portal="student"][data-view="review"] .v6-answer-dock{min-height:50px}
 body[data-portal="student"][data-view="review"] .review-uncertain,body[data-portal="student"][data-view="review"] .v6-answer-dock>.btn{min-height:50px!important;font-size:16px}
 body[data-portal="student"][data-view="review"] .spelling-label{font-size:14px}
 body[data-portal="student"][data-view="review"] .spelling-field>.input{font-size:26px!important;min-height:52px}
 body[data-portal="student"][data-view="review-report"] .review-report{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(0,1fr);gap:20px;padding-top:18px}
 body[data-portal="student"][data-view="review-report"] .review-report-hero{grid-column:1/-1;padding-bottom:0}
 body[data-portal="student"][data-view="review-report"] .review-report-hero h1{font-size:30px}
 body[data-portal="student"][data-view="review-report"] .review-summary{margin:0;padding:22px;align-self:start}
 body[data-portal="student"][data-view="review-report"] .review-summary p{font-size:15px;margin-top:12px}
 body[data-portal="student"][data-view="review-report"] .review-summary b{font-size:15px}
 body[data-portal="student"][data-view="review-report"] .review-report-actions{align-self:start}
 body[data-portal="student"][data-view="review-report"] .report-section{grid-column:1/-1;margin-top:12px}
 body[data-portal="student"] .review-focus-list{grid-template-columns:repeat(2,minmax(0,1fr))}
 body[data-portal="student"] .review-focus-list>article{border-bottom:1px solid #e7efed}
 body[data-portal="student"] .review-focus-list>article:nth-child(odd){border-right:1px solid #e7efed}
 body[data-portal="student"][data-view="report"] .report-hero h1{max-width:none;font-size:32px}
 body[data-portal="student"] .report-rows{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 28px}
 body[data-portal="student"] .report-actions{width:min(100%,1040px)}
 body[data-portal="student"] .report-stat b{font-size:36px}
}
/* 宽而矮的窗口：题干和录音在左，选项/输入及反馈操作在右。 */
body[data-portal="student"].v7-landscape{max-width:1200px}
body[data-portal="student"].v7-landscape .topbar{max-width:1120px}
body[data-portal="student"].v7-landscape[data-view="review-report"] .review-report{display:grid;grid-template-columns:minmax(0,1.1fr) minmax(0,1fr);gap:12px 18px}
body[data-portal="student"].v7-landscape[data-view="review-report"] .review-report-hero{grid-column:1/-1;padding:0}
body[data-portal="student"].v7-landscape[data-view="review-report"] .review-summary{margin:0;align-self:start}
body[data-portal="student"].v7-landscape[data-view="review-report"] .review-report-actions{align-self:start;gap:6px}
body[data-portal="student"].v7-landscape[data-view="review-report"] .report-section{grid-column:1/-1}
body[data-portal="student"].v7-landscape .study-brandbar{max-width:1120px;width:100%;height:54px;padding:0 24px}
body[data-portal="student"].v7-landscape[data-view="study"]{padding-bottom:0;overflow:hidden}
body[data-portal="student"].v7-landscape .study-shell{max-width:1120px;height:calc(var(--v7-vh,100dvh) - 54px);margin:0 auto;padding:14px 24px 18px;display:flex;flex-direction:column;gap:12px;min-height:0}
body[data-portal="student"].v7-landscape .study-head{flex:none;margin:0}
body[data-portal="student"].v7-landscape .study-head .progress{margin-top:7px}
body[data-portal="student"].v7-landscape .study-note{display:none}
body[data-portal="student"].v7-landscape .quiz-card{flex:1;min-height:0;display:grid;grid-template-columns:minmax(0,.85fr) minmax(0,1.15fr);grid-template-rows:auto minmax(0,1fr) auto auto;column-gap:32px;row-gap:10px;padding:28px;border-radius:24px;text-align:left;overflow:auto}
body[data-portal="student"].v7-landscape .question-type{grid-column:1;grid-row:1;display:block;align-self:start}
body[data-portal="student"].v7-landscape .question-type .badge{margin:0 0 6px}
body[data-portal="student"].v7-landscape .quiz-card h1{grid-column:1;grid-row:2;margin:0;align-self:center;font-size:36px;line-height:1.5}
body[data-portal="student"].v7-landscape .quiz-card h1 small{display:block;margin:0 0 8px!important}
body[data-portal="student"].v7-landscape .quiz-options{grid-column:2;grid-row:1/5;grid-template-columns:1fr;grid-template-rows:repeat(4,minmax(52px,1fr));gap:12px;align-self:center;width:100%}
body[data-portal="student"].v7-landscape .option{min-height:64px;font-size:25px;padding:16px 20px}
body[data-portal="student"].v7-landscape .skip{grid-column:1;grid-row:3;position:static;transform:none;left:auto;right:auto;min-height:48px;padding:10px 12px;width:100%;border:1px solid #d9e2d4;border-radius:12px;text-align:center;font-size:14px;background:#f5f8f1;align-self:end}
body[data-portal="student"].v7-landscape .answer-result{grid-column:1;grid-row:3;padding:10px 0 0;font-size:14px}
body[data-portal="student"].v7-landscape .result-next-hint{grid-column:1;grid-row:4;margin:0;font-size:13px}
body[data-portal="student"].v7-landscape .study-shell>.feedback{flex:none;margin:0;padding:10px 15px}
body[data-portal="student"].v7-landscape .word-panel{display:grid;grid-template-columns:minmax(0,.85fr) minmax(0,1.15fr);gap:18px 30px;padding:26px;flex:1;min-height:0;overflow:auto;align-content:center}
body[data-portal="student"].v7-landscape .word-title{grid-column:1;grid-row:1;margin:0}
body[data-portal="student"].v7-landscape .word-title h1{font-size:42px}
body[data-portal="student"].v7-landscape .meaning-line{grid-column:1;grid-row:2;margin:0;font-size:20px}
body[data-portal="student"].v7-landscape .word-detail{grid-column:2;grid-row:1/3;display:grid;grid-template-columns:1fr;gap:24px}
body[data-portal="student"].v7-landscape .detail-en{font-size:22px}
body[data-portal="student"].v7-landscape .detail-cn{font-size:15px}
body[data-portal="student"].v7-landscape .lecture-group{grid-column:1/-1;margin:0;padding-top:14px}
body[data-portal="student"].v7-landscape .learning-actions{position:static;transform:none;left:auto;right:auto;width:100%;padding:0;background:none;border:0;display:flex;flex-direction:row;gap:20px;justify-content:flex-end;flex:none}
body[data-portal="student"].v7-landscape .learning-actions>.note{display:block;max-width:none;margin-right:auto;text-align:left}
body[data-portal="student"].v7-landscape .learning-actions>.btn{width:auto;max-width:none;min-width:220px}
body[data-portal="student"].v7-landscape[data-view="review"] .review-shell{width:min(100%,1120px);max-width:1120px;padding:18px 24px;gap:12px}
body[data-portal="student"].v7-landscape[data-view="review"] .review-question{display:grid;grid-template-columns:minmax(0,.85fr) minmax(0,1.15fr);grid-template-rows:minmax(0,1fr) auto auto;gap:12px 28px;padding:24px!important;overflow:auto}
body[data-portal="student"].v7-landscape[data-view="review"] .v6-prompt{grid-column:1;grid-row:1/4;padding:26px;background:#edf6f6;border-radius:18px;min-height:0;justify-content:center;align-self:stretch;gap:12px}
body[data-portal="student"].v7-landscape[data-view="review"] .v6-meaning{font-size:clamp(27px,3vw,40px)}
body[data-portal="student"].v7-landscape[data-view="review"] .v6-type{font-size:14px}
body[data-portal="student"].v7-landscape[data-view="review"] .review-listen{min-height:110px;background:#fff}
body[data-portal="student"].v7-landscape[data-view="review"] .audio-hint{font-size:13px;line-height:1.6}
body[data-portal="student"].v7-landscape[data-view="review"] .review-options{grid-column:2;grid-row:1;grid-template-columns:1fr;grid-template-rows:repeat(4,minmax(52px,1fr));max-height:420px;min-height:220px;gap:12px!important;align-self:stretch}
body[data-portal="student"].v7-landscape[data-view="review"] .review-option{padding:14px 16px!important;min-height:52px!important;font-size:22px}
body[data-portal="student"].v7-landscape[data-view="review"] #review-spelling{grid-column:2;grid-row:1;align-self:center;flex:none;min-height:0;gap:16px}
body[data-portal="student"].v7-landscape[data-view="review"] .review-feedback{grid-column:2;grid-row:2;margin:0}
body[data-portal="student"].v7-landscape[data-view="review"] .v6-feedback-space{display:none}
body[data-portal="student"].v7-landscape[data-view="review"] .v6-answer-dock{grid-column:2;grid-row:3;margin:0;min-width:0}
/* 低可视高度（手机横屏或键盘）采用2乘2选项，题干仍完整保留。 */
body[data-portal="student"].v7-landscape.v7-compact .study-brandbar{height:38px;padding:0 16px}
body[data-portal="student"].v7-landscape.v7-compact .study-shell{height:calc(var(--v7-vh,100dvh) - 38px);padding:6px 12px 8px;gap:6px}
body[data-portal="student"].v7-landscape.v7-compact .study-head .btn{min-height:30px;padding:3px 0}
body[data-portal="student"].v7-landscape.v7-compact .study-head .progress{margin-top:4px;height:3px}
body[data-portal="student"].v7-landscape.v7-compact .quiz-card{padding:12px 16px;gap:5px 20px}
body[data-portal="student"].v7-landscape.v7-compact .question-type .badge{font-size:10px;margin:0}
body[data-portal="student"].v7-landscape.v7-compact .question-type p{display:none}
body[data-portal="student"].v7-landscape.v7-compact .quiz-card h1{font-size:25px;line-height:1.35}
body[data-portal="student"].v7-landscape.v7-compact .quiz-card h1 small{font-size:12px!important;margin:0 0 4px!important}
body[data-portal="student"].v7-landscape.v7-compact .quiz-options{grid-template-columns:repeat(2,minmax(0,1fr));grid-template-rows:repeat(2,minmax(52px,1fr));gap:8px}
body[data-portal="student"].v7-landscape.v7-compact .option{min-height:52px;padding:8px 9px;font-size:17px;gap:8px}
body[data-portal="student"].v7-landscape.v7-compact .skip{min-height:40px;padding:7px;font-size:12px}
body[data-portal="student"].v7-landscape.v7-compact .answer-result{font-size:12px;line-height:1.4;padding:0;gap:2px}
body[data-portal="student"].v7-landscape.v7-compact .result-next-hint{font-size:11px;line-height:1.4}
body[data-portal="student"].v7-landscape.v7-compact .word-panel{padding:12px 16px;gap:8px 20px;align-content:start}
body[data-portal="student"].v7-landscape.v7-compact .word-title h1{font-size:28px;margin:0 0 4px}
body[data-portal="student"].v7-landscape.v7-compact .word-title .kicker{display:none}
body[data-portal="student"].v7-landscape.v7-compact .phonetic{font-size:12px}
body[data-portal="student"].v7-landscape.v7-compact .meaning-line{padding:8px 10px;font-size:16px}
body[data-portal="student"].v7-landscape.v7-compact .word-detail{gap:12px;grid-template-columns:repeat(2,minmax(0,1fr))}
body[data-portal="student"].v7-landscape.v7-compact .detail-en{font-size:15px;line-height:1.5}
body[data-portal="student"].v7-landscape.v7-compact .detail-cn{font-size:12px;line-height:1.5;margin-top:4px}
body[data-portal="student"].v7-landscape.v7-compact .detail-label{font-size:9px;letter-spacing:0;margin-bottom:4px}
body[data-portal="student"].v7-landscape.v7-compact .lecture-group{display:none}
body[data-portal="student"].v7-landscape.v7-compact .study-shell>.feedback{font-size:11px;line-height:1.4;padding:5px 10px}
body[data-portal="student"].v7-landscape.v7-compact .learning-actions>.note{font-size:11px}
body[data-portal="student"].v7-landscape.v7-compact .learning-actions>.btn{min-height:40px;min-width:185px;padding:8px 14px;font-size:14px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-shell{padding:5px 12px;gap:5px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-top,body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-top>.btn{min-height:30px;font-size:12px;padding-top:3px;padding-bottom:3px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-heading{min-height:20px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-heading h1{font-size:16px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-heading>p:last-child{font-size:11px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-question{padding:10px 12px!important;gap:6px 16px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .v6-prompt{padding:14px;gap:7px;min-height:0}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .v6-meaning{font-size:26px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-options{grid-template-columns:repeat(2,minmax(0,1fr));grid-template-rows:repeat(2,minmax(44px,1fr));gap:6px!important;min-height:94px;max-height:190px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-option{padding:7px 9px!important;min-height:44px!important;font-size:16px;gap:6px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-option small{font-size:9px;white-space:normal}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-feedback{padding:6px 8px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-feedback p,body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-feedback b{font-size:12px;line-height:1.4}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-feedback .v6-choice-note{font-size:11px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-listen{min-height:60px;margin:0}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-listen span{font-size:18px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-sentence{font-size:20px;line-height:1.5}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-translation{font-size:12px;line-height:1.5}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] #review-spelling{gap:5px;min-height:0}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .spelling-label{font-size:11px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .spelling-field>.input{font-size:22px!important;min-height:40px;padding:5px 10px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] #review-spelling>.btn{min-height:38px;padding:6px}
body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .v6-answer-dock,body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .review-uncertain,body[data-portal="student"].v7-landscape.v7-compact[data-view="review"] .v6-answer-dock>.btn{min-height:36px!important;font-size:13px;padding:6px}
/* 横屏刘海及边缘手势安全区域。可用区域仍由visualViewport决定。 */
body[data-portal="student"].v7-landscape{--v7-side:24px}
body[data-portal="student"].v7-landscape.v7-compact{--v7-side:12px}
body[data-portal="student"].v7-landscape .study-brandbar,body[data-portal="student"].v7-landscape .study-shell,body[data-portal="student"].v7-landscape[data-view="review"] .review-shell{padding-left:max(var(--v7-side),env(safe-area-inset-left,0px));padding-right:max(var(--v7-side),env(safe-area-inset-right,0px))}