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*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font:16px/1.7 "Microsoft YaHei","PingFang SC",sans-serif}a{color:var(--blue);text-underline-offset:4px}button,input,textarea{font:inherit}button{cursor:pointer;color:inherit}button,a{-webkit-tap-highlight-color:transparent}button:focus-visible,a:focus-visible,summary:focus-visible,input:focus-visible{outline:3px solid #79a8d7;outline-offset:3px}[hidden]{display:none!important}.skip-link{position:fixed;left:12px;top:-70px;background:white;padding:8px;z-index:10}.skip-link:focus{top:8px}.site-header{height:70px;padding:0 28px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line)}.brand{display:flex;align-items:center;gap:12px;color:var(--ink);text-decoration:none;font-size:16px;font-weight:600}.brand small{display:block;font-size:12px;font-weight:400;color:var(--muted);line-height:1.4}.brand-mark{display:grid;place-items:center;width:34px;height:34px;border:1px solid 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solid var(--blue);padding:5px 14px}.answer-feedback.correct{border-color:var(--green)}.answer-feedback.incorrect{border-color:var(--red)}.answer-feedback strong{display:block}.answer-feedback p{font-size:14px}.question-list{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:18px}.question-list a{padding:5px 10px;font-size:14px;text-decoration:none;border:1px solid var(--line);border-radius:4px}.question-list [aria-current]{background:var(--tint);border-color:#97b4d0}.results-table{width:100%;border-collapse:collapse;font-size:14px}.results-table th,.results-table td{text-align:left;padding:12px 8px;border-bottom:1px solid var(--line);vertical-align:top}.results-table th{color:var(--muted);font-weight:400}.results-table td:last-child{white-space:nowrap}.download-link{display:inline-block;margin:12px 0}.help-list{list-style:none;padding:0}.help-list li{border-bottom:1px solid var(--line);padding:12px 0}.help-list a{display:block;text-decoration:none}.note-box{margin-top:20px;font-size:13px}.note-box textarea{width:100%;min-height:90px;padding:8px;border:1px solid var(--line);border-radius:4px;background:var(--paper);color:var(--ink)}.error-note{color:var(--red);font-size:13px}.inline-answer{font-size:14px;color:var(--blue);background:none;border:0;padding:8px 0;text-decoration:underline}
@media(min-width:1500px){.workspace{padding-left:48px;padding-right:48px}.workbench{gap:40px;grid-template-columns:minmax(0,1fr) 200px}}
@media(max-width:1050px){.learning-shell{grid-template-columns:170px minmax(0,1fr)}.workspace{padding:20px}}
@media(max-width:900px){.workbench{grid-template-columns:minmax(0,1fr)}.actions{position:static;border-left:0;border-top:1px solid var(--line);padding:16px 0 0;max-width:none}.actions .primary{max-width:320px}.actions .secondary{display:inline-block;margin-right:20px}.actions p{margin-bottom:10px}}
@media(max-width:680px){.site-header{padding:0 16px;height:62px}.learning-shell{display:block}.sidebar{padding:8px 12px;border-right:0;border-bottom:1px solid var(--line);gap:6px}.sidebar nav{flex-direction:row;flex-wrap:wrap;gap:2px}.nav-group,.nav-link small{display:none}.nav-link{font-size:13px;padding:6px 8px}.local-records{margin:0;padding:0 8px;font-size:12px}.local-records summary{min-height:24px}.workspace{padding:16px 16px 32px}.journey{gap:6px;font-size:12px;margin-bottom:16px;padding-bottom:10px}h1{font-size:20px}.tabs{margin-bottom:14px}.tabs a{padding:6px 9px;font-size:14px}.results-table th,.results-table td{padding:9px 4px;font-size:13px}.problem-figure{margin:0 -4px}.actions .primary{max-width:none}.choice{padding:7px 12px}.brand small{font-size:11px}#board{min-height:240px}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}
.mobile-question{display:none}.source-diagram{display:block;max-width:100%;width:auto;max-height:95px;margin:16px 0}.original-option{padding-left:1.6em;text-indent:-1.6em}@media(max-width:680px){.q4-full-image{display:none}.mobile-question{display:block}.mobile-question p{font-size:16px;line-height:1.85}.mobile-question .source-diagram{max-width:100%;max-height:85px}.mobile-question .source{display:inline-block}}
.ai-companion{max-width:800px;margin-top:18px;border-top:1px solid var(--line);padding-top:16px}.ai-intro{display:flex;align-items:baseline;gap:10px;margin-bottom:8px}.ai-intro strong{font-size:17px;color:var(--blue)}.ai-intro span,.ai-guide,.ai-progress{color:var(--muted);font-size:14px}.ai-guide{margin:0 0 18px}.ai-turn,.ai-prompt{border-left:3px solid #a8bfd5;padding:8px 14px;margin:12px 0;background:var(--rail)}.ai-turn.ai-correct{border-left-color:var(--green)}.ai-turn.ai-retry{border-left-color:#d39b4a}.ai-speaker{font-size:12px;color:var(--muted);margin:0 0 3px}.ai-choice{margin:0;font-weight:600}.ai-response{margin:6px 0 0;font-size:14px}.ai-prompt{background:var(--tint);border-left-color:var(--blue);font-size:16px}.ai-prompt p:last-child{margin:0}.ai-options{display:grid;gap:8px;margin:12px 0}.ai-option{display:block;text-align:left;background:white;border:1px solid var(--line);border-radius:5px;padding:9px 12px;line-height:1.55;color:var(--ink)}.ai-option:hover,.ai-option:focus-visible{border-color:#87a8c7;background:var(--tint)}.ai-progress{margin-top:12px}.ai-complete{border-top:1px solid var(--line);margin-top:18px;padding-top:12px}.ai-complete h2{margin-top:0}.ai-complete ol{padding-left:22px}
.actions .ai-side-options{margin:12px 0}.actions .ai-option{width:100%;font-size:14px;padding:8px 10px}.actions .ai-progress{margin:10px 0;font-size:12px}.actions .secondary{width:100%;text-align:left}
/* 260908：把学生当前要做的事做成清晰、可识别的右侧操作区。 */
.workbench{grid-template-columns:minmax(0,1fr) 270px;gap:30px}
.actions{background:#f4f8fc;border:1px solid #cfdeec;border-radius:10px;padding:18px 18px 20px;box-shadow:0 6px 18px rgba(33,67,98,.08)}
.actions #actionLabel{display:block;color:var(--blue);font-size:15px;font-weight:600;margin-bottom:10px}
.actions #actionHint{font-size:15px;line-height:1.7;margin-bottom:16px}
.actions .primary{min-height:46px;font-size:15px;font-weight:600}
.actions .ai-side-options{margin:14px 0 12px}
.actions .ai-option{min-height:50px;font-size:15px;line-height:1.55;padding:10px 12px;text-align:left;border:1px solid #b8cde0;background:#fff;border-radius:7px}
.actions .ai-option:hover,.actions .ai-option:focus-visible{border-color:var(--blue);background:#edf5fc}
.actions .ai-progress{font-size:13px;line-height:1.55}
@media(min-width:1500px){.workbench{grid-template-columns:minmax(0,1fr) 290px}}
@media(max-width:1050px) and (min-width:901px){.workbench{grid-template-columns:minmax(0,1fr) 245px;gap:22px}}
/* 右侧只负责承载当前操作，不做额外卡片装饰。 */
.actions{background:transparent;border:0;border-left:1px solid var(--line);border-radius:0;box-shadow:none;padding:0 0 0 24px}
.retest-flow{margin:22px 0;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}
.retest-flow p{display:grid;grid-template-columns:145px minmax(0,1fr);gap:18px;margin:0;padding:12px 0;border-bottom:1px solid var(--line)}
.retest-flow p:last-child{border-bottom:0}
.retest-flow strong{font-size:15px;color:var(--ink)}
.retest-flow span{font-size:14px;color:var(--muted)}
@media(max-width:680px){.retest-flow p{display:block}.retest-flow span{display:block;margin-top:3px}}
@media(max-width:900px){.actions{border-left:0;border-top:1px solid var(--line);padding:16px 0 0}}
/* 问题探究内容全部归入右侧，给学生操作区留出足够宽度。 */
.workbench{grid-template-columns:minmax(0,1fr) 320px;gap:32px}
.actions .inquiry-side-content .ai-companion{max-width:none;margin-top:14px;border-top:1px solid var(--line);padding-top:14px}
.actions .ai-intro{display:block;margin-bottom:10px}
.actions .ai-intro strong{display:block;font-size:16px}
.actions .ai-intro span{display:block;font-size:13px;margin-top:2px}
.actions .ai-guide{font-size:13px;line-height:1.6;margin-bottom:10px}
.actions .ai-turn{background:transparent;padding:5px 10px;margin:8px 0}
.actions .ai-complete{margin-top:12px;padding-top:10px}
@media(min-width:1500px){.workbench{grid-template-columns:minmax(0,1fr) 340px}}
@media(max-width:1050px) and (min-width:901px){.workbench{grid-template-columns:minmax(0,1fr) 285px;gap:22px}}
@media(max-width:900px){.workbench{grid-template-columns:minmax(0,1fr)}}
@media(max-width:900px) and (min-width:501px){.workbench{grid-template-columns:minmax(0,1fr) 245px;gap:18px}.actions{position:sticky;top:16px;border-left:1px solid var(--line);border-top:0;padding:0 0 0 16px}}
/* 260909：问题探究需要更大的右侧输入区；中间题图适当收窄。 */
.workbench{grid-template-columns:minmax(0,1fr) 410px;gap:28px}
@media(min-width:1500px){.workbench{grid-template-columns:minmax(0,1fr) 450px;gap:36px}}
@media(max-width:1250px) and (min-width:901px){.workbench{grid-template-columns:minmax(0,1fr) 350px;gap:22px}}
@media(max-width:900px){.workbench{grid-template-columns:minmax(0,1fr)}.actions{position:static;border-left:0;border-top:1px solid var(--line);padding:18px 0 0}}
.problem-inquiry-panel{max-width:none}
.ai-empty{color:var(--muted);font-size:13px;margin:16px 0}
.ai-chat-log{border-top:1px solid var(--line);margin:16px 0 14px}
.ai-chat-turn{padding:9px 0;border-bottom:1px solid var(--line)}
.ai-chat-turn p{margin:3px 0;font-size:14px;line-height:1.65}
.ai-chat-speaker{color:var(--blue);font-size:12px!important}
.ai-chat-user p:last-child{color:var(--ink)}
.ai-chat-assistant p:last-child{color:var(--ink)}
.ai-question-form{border-top:1px solid var(--line);padding-top:14px;margin-top:14px}
.ai-question-form label{display:block;color:var(--ink);font-size:13px;margin-bottom:6px}
.ai-question-input,.ai-question-form textarea{display:block;width:100%;min-height:104px;resize:vertical;border:1px solid #b8cde0;border-radius:4px;background:#fff;color:var(--ink);padding:9px 10px;line-height:1.6}
.ai-question-form .primary{margin-top:10px}
.ai-question-form .primary:disabled{opacity:.65;cursor:wait}
@media(max-width:900px){.ai-question-form{max-width:620px}}
.pmuc-text{white-space:pre-wrap;overflow-wrap:anywhere}
.pmuc-history,.pmuc-prediction,.pmuc-error-detail{font-size:13px;color:var(--muted);margin:10px 0}
.pmuc-history summary,.pmuc-prediction summary{padding:5px 0}
.pmuc-prediction p{color:var(--ink);font-size:14px}
.actions .ai-chat-log:empty,.actions #actionHint:empty,.actions #problemInquiryStatus:empty{display:none}
.actions .ai-chat-log{margin-top:8px;border-top:0}
.actions .primary{text-align:center;text-decoration:none}
.ai-question-form textarea:focus-visible{outline:2px solid #79a8d7;outline-offset:2px}
@media(max-width:680px){.learning-shell{overflow-x:clip}}
.nav-title{margin:0 10px 10px;color:var(--ink);font-size:13px;font-weight:600}.tabs-caption{align-self:center;padding:7px 8px 7px 0;color:var(--muted);font-size:12px;white-space:nowrap}
.tab-locked{display:block;padding:7px 10px;color:#a2adb8;font-size:14px;border-bottom:2px solid transparent;cursor:not-allowed}
.tabs a[data-recommended="true"]{color:var(--blue)}
.tab-suggested{display:inline-block;margin-left:4px;font-size:10px;line-height:1;color:var(--blue);font-weight:600;vertical-align:1px}
.explanation-mode-tabs{display:flex;gap:0;border-bottom:1px solid var(--line);margin:0 0 14px;overflow-x:auto}
.explanation-mode-tabs button{flex:1 0 auto;border:0;border-bottom:2px solid transparent;background:transparent;padding:8px 7px;color:var(--muted);font-size:13px}
.explanation-mode-tabs button[aria-pressed="true"]{color:var(--blue);border-bottom-color:var(--blue);font-weight:600}
.explanation-mode-tabs small{display:block;font-size:10px;font-weight:400;line-height:1.2;color:var(--blue)}
/* 概念理解：只用分隔线组织讲解与操作，不增加卡片。 */
.concept-panel{margin-top:8px}
.concept-lesson{margin-top:16px;padding-top:14px;border-top:1px solid var(--line)}
.concept-lesson h2{font-size:16px;line-height:1.55;margin:0 0 10px}
.concept-lesson p{font-size:14px;line-height:1.75;margin:9px 0}
.concept-lesson .source{font-size:12px;color:var(--muted)}
.concept-example{padding-left:12px;border-left:2px solid #b4c9dc}
.concept-force-diagram{display:block;width:100%;max-width:390px;margin:10px auto}
.concept-topics{display:flex;flex-wrap:wrap;gap:8px 16px;border-bottom:1px solid var(--line);margin:6px 0 18px}
.concept-topics button{background:none;border:0;border-bottom:2px solid transparent;padding:6px 0;font-size:13px;color:var(--muted)}
.concept-topics button[aria-pressed="true"]{border-bottom-color:var(--blue);color:var(--blue)}
.concept-options{display:grid;margin:12px 0}
.concept-choice{border:0;border-bottom:1px solid var(--line);border-radius:0;background:none;padding:12px 4px;text-align:left;line-height:1.6;font-size:15px;min-height:44px}
.concept-choice[aria-pressed="true"]{color:var(--blue);font-weight:600;border-left:2px solid var(--blue);padding-left:10px}
.concept-choice:disabled{cursor:default;opacity:1}
.concept-feedback{font-size:14px;line-height:1.8;margin:14px 0;white-space:pre-wrap}
.concept-feedback:empty{display:none}
.concept-next{margin-top:16px}
.concept-resources{border-top:1px solid var(--line);margin-top:14px;padding-top:5px}
.concept-resources .secondary{margin-top:0}
.concept-help{margin-top:24px;border-top:1px solid var(--line);padding-top:12px}
.concept-help summary{font-size:14px;color:var(--blue);padding:4px 0}
.concept-help label{display:block;font-size:13px;margin:12px 0 6px}
.concept-help textarea{display:block;width:100%;min-height:92px;padding:10px;border:1px solid #b8cde0;border-radius:3px;resize:vertical;line-height:1.65}
.concept-help .primary{margin-top:10px}
.concept-help .primary:disabled{opacity:.65;cursor:wait}
.concept-help textarea:focus-visible{outline:2px solid #79a8d7;outline-offset:2px}
.concept-chat-turn{border-bottom:1px solid var(--line);padding:10px 0}
.concept-chat-turn p{white-space:pre-wrap;overflow-wrap:anywhere;font-size:14px;line-height:1.8}
.concept-help #conceptHelpStatus{margin:10px 0;font-size:13px}
.concept-help #conceptHelpStatus:empty{display:none}
.multimodal-input-tools{display:flex;align-items:center;gap:6px;margin-top:7px;min-height:30px}
.multimodal-button{appearance:none;display:inline-flex!important;align-items:center;justify-content:center;gap:4px;width:auto!important;min-height:30px!important;margin:0!important;padding:4px 9px!important;border:1px solid #b9cfe3!important;border-radius:5px!important;background:#f7fbff!important;color:var(--blue)!important;font-size:12px!important;font-weight:600;line-height:1.2;cursor:pointer}
.multimodal-button:hover{background:var(--tint)!important;border-color:#8eafce!important}
.multimodal-button:focus-visible{outline:3px solid #79a8d7;outline-offset:2px}
.multimodal-button.is-recording{background:#fff0ed!important;border-color:#c96c5b!important;color:#a54a3b!important;box-shadow:0 0 0 3px rgba(201,108,91,.14)}
.multimodal-button.has-recording{background:#eaf6ef!important;border-color:#81b995!important;color:#2f7048!important}
.multimodal-file{position:absolute!important;width:1px!important;height:1px!important;overflow:hidden!important;clip:rect(0 0 0 0)!important;clip-path:inset(50%)!important}
.multimodal-hint{color:var(--muted);font-size:11px;line-height:1.3}
.multimodal-input-preview{display:flex;align-items:flex-start;gap:8px;margin-top:7px;padding:7px 8px;border-left:3px solid #8eafce;background:#f7fafc;font-size:12px;line-height:1.55;overflow-wrap:anywhere}
.multimodal-input-preview img{width:52px;height:52px;object-fit:cover;border-radius:3px;border:1px solid #c8d9e7;flex:0 0 auto}
.multimodal-ocr-result{min-width:0}.multimodal-ocr-result p{margin:2px 0}.multimodal-formulas{display:flex;flex-wrap:wrap;gap:4px;margin-top:3px}.multimodal-formulas code{padding:1px 4px;border-radius:3px;background:#fff;color:var(--ink);font-family:ui-monospace,monospace}
.multimodal-warning{color:#9a6427}.multimodal-voice-result{margin:0;color:var(--ink)}
.multimodal-input-status{min-height:0;margin:5px 0 0;color:var(--muted);font-size:11px;line-height:1.45;overflow-wrap:anywhere}.multimodal-input-status:empty{display:none}.multimodal-input-status[data-error="true"]{color:#a4513d}
.concept-original-mobile{display:none}
.skip-link:not(:focus){clip-path:inset(50%);width:1px;height:1px;overflow:hidden}
.concept-context{font-size:13px;color:var(--muted)}
.concept-type{padding-bottom:12px;border-bottom:1px solid var(--line)}
.concept-thinking-path{padding-left:24px;margin:16px 0}
.concept-thinking-path li{padding-left:4px;margin:14px 0;font-size:14px}
.concept-thinking-path li::marker{color:var(--blue)}
.concept-thinking-path li p{margin:4px 0}
@media(max-width:1100px){
  .concept-original-desktop{display:none}
  .concept-original-mobile{display:block;font-size:16px;line-height:1.85}
  .concept-source-device{display:block;width:140px;margin:12px 0}
  .concept-source-device svg{display:block;width:140px;height:272px}
}
.written-work{margin:20px 0 8px;padding-top:4px;border-top:1px solid var(--line)}
.answer-form{margin:0}
.answer-form>.primary{margin-top:20px}
.part-answer{display:block;margin:16px 0}
.part-answer strong{display:block;font-size:14px;font-weight:600;margin-bottom:7px}
.part-answer textarea{display:block;width:100%;min-height:98px;padding:10px;border:1px solid #b8cde0;border-radius:4px;background:#fff;color:var(--ink);resize:vertical;line-height:1.65}
.part-answer textarea:focus-visible{outline:2px solid #79a8d7;outline-offset:2px}
.submitted-work{border-top:1px solid var(--line);margin:8px 0 18px}
.submitted-part{padding:10px 0;border-bottom:1px solid var(--line)}
.submitted-part strong{display:block;font-size:14px}
.submitted-part p{white-space:pre-wrap;font-size:14px;margin:6px 0 0}
.transfer-card{margin:20px 0;padding:16px;border-top:1px solid var(--line);border-bottom:1px solid var(--line);background:#fbfdff}
.transfer-card h3{margin-top:0}
.inquiry-prompt{padding:12px;border-left:3px solid var(--blue);background:var(--tint);font-size:15px;line-height:1.7}
.inquiry-feedback{padding:9px 11px;border-left:3px solid #d39b4a;background:#fffaf0;font-size:14px;line-height:1.7}
.inquiry-history{font-size:12px;margin:5px 0;color:var(--muted)}
.inquiry-history.correct{color:var(--green)}
.inquiry-history.incorrect{color:#a36a25}
.return-nav{margin:0 0 14px;font-size:13px}.return-nav a{color:var(--blue);text-decoration:none}.return-nav a:hover{text-decoration:underline}
.paper-links{display:flex;align-items:center;flex-wrap:wrap;gap:8px 22px;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:10px 0;margin:18px 0}.paper-links span{font-size:13px;color:var(--muted)}.paper-links .download-link{margin:0;font-size:14px;text-decoration:none}

/* 260910：右侧对话区固定在视口内；历史记录保留，但不再把整页向下撑长。 */
.actions{min-height:0;max-height:calc(100vh - 48px);overflow:hidden}
.actions #secondaryActions{min-width:0;min-height:0;max-height:calc(100vh - 174px);overflow-y:auto;overflow-x:hidden;overscroll-behavior:contain;scrollbar-gutter:stable;padding:0 8px 2px 0}
.actions #secondaryActions>*{min-width:0}
.actions #secondaryActions .ai-chat-log,.actions #secondaryActions .concept-chat{min-width:0}
.actions #secondaryActions .ai-question-form,.actions #secondaryActions .concept-help form{position:sticky;bottom:0;z-index:2;background:var(--paper);padding:12px 0 2px;margin-bottom:0}
.actions #secondaryActions .ai-question-form{border-top:1px solid var(--line)}
.actions #secondaryActions .concept-help form{border-top:1px solid var(--line)}
.actions #secondaryActions .pmuc-history,.actions #secondaryActions .conversation-history{margin:8px 0}
.actions #secondaryActions .pmuc-history summary,.actions #secondaryActions .conversation-history summary{padding:7px 0;color:var(--blue)}
.actions #secondaryActions .ai-chat-turn,.actions #secondaryActions .concept-chat-turn{overflow-wrap:anywhere}
@media(max-width:900px){.actions{max-height:none;overflow:visible}.actions #secondaryActions{max-height:none;overflow:visible;padding-right:0}.actions #secondaryActions .ai-question-form,.actions #secondaryActions .concept-help form{position:static}}

/* 260911：问题探究清爽版。保留题目、问题和回答，不用重复提示与分隔线制造层级。 */
.actions:has(.problem-inquiry-panel) #actionHint,
.actions:has(.problem-inquiry-panel) #nextButton{display:none}
.actions:has(.problem-inquiry-panel){padding-top:2px}
.actions .problem-inquiry-panel{margin:0;padding:0;background:transparent;border:0}
.actions .problem-inquiry-panel .ai-chat-log{display:grid;gap:16px;margin:0;border:0}
.actions .problem-inquiry-panel .ai-chat-turn{margin:0;padding:0;border:0;background:transparent}
.actions .problem-inquiry-panel .ai-chat-speaker{margin:0 0 5px;color:var(--muted);font-size:12px;line-height:1.3}
.actions .problem-inquiry-panel .pmuc-text{margin:0;font-size:14px;line-height:1.75;white-space:pre-wrap;overflow-wrap:anywhere}
.actions .problem-inquiry-panel .ai-chat-assistant .pmuc-text{padding:10px 12px;border-left:3px solid var(--blue);border-radius:0 5px 5px 0;background:var(--tint)}
.actions .problem-inquiry-panel .ai-chat-user .pmuc-text{padding-left:12px;color:var(--ink)}
.actions .problem-inquiry-panel .pmuc-history{margin:0 0 16px;border:0;color:var(--muted)}
.actions .problem-inquiry-panel .pmuc-history summary{min-height:0;padding:0;color:var(--blue);font-size:12px}
.actions .problem-inquiry-panel .pmuc-prediction{margin:0 0 16px;border:0;color:var(--muted)}
.actions .problem-inquiry-panel .pmuc-prediction summary{min-height:0;padding:0;font-size:12px}
.actions .problem-inquiry-panel .pmuc-prediction p{margin:7px 0 0;padding-left:12px;color:var(--ink);font-size:13px;line-height:1.6}
.actions .problem-inquiry-panel .ai-question-form{margin:20px 0 0;padding:16px 0 0;border-top:0;background:transparent}
.actions .problem-inquiry-panel .ai-question-form label{display:block;margin:0 0 6px;color:var(--muted);font-size:12px}
.actions .problem-inquiry-panel .ai-question-form textarea{min-height:82px;padding:9px 10px;border:1px solid #c8d9e7;border-radius:4px;box-shadow:none;font-size:14px;line-height:1.65}
.actions .problem-inquiry-panel .ai-question-form .primary{margin-top:8px;min-height:40px;font-size:14px}
.actions .problem-inquiry-panel .error-note{margin:14px 0 8px;font-size:13px;line-height:1.6}
.actions .problem-inquiry-panel .ai-progress{margin:12px 0 0;color:var(--muted);font-size:12px;line-height:1.5}
.actions .problem-inquiry-panel .concept-feedback{display:none}
.actions .problem-inquiry-panel .primary + .primary{margin-top:8px}
.actions .problem-inquiry-panel .secondary{font-size:12px}

/* 260911：原题作答采用最低负担证据。完整过程只作为折叠补充，不阻塞学生继续。 */
.quick-signal{border:0;margin:16px 0 0;padding:0}
.quick-signal legend{font-size:13px;color:var(--muted);padding:0;margin-bottom:7px}
.quick-signal-options{display:flex;flex-wrap:wrap;gap:6px 16px}
.quick-signal-options label{font-size:13px;color:var(--ink);white-space:nowrap}
.quick-signal-options input{accent-color:var(--blue);margin-right:5px}
.optional-evidence{border-top:1px solid var(--line);margin-top:16px;padding-top:10px}
.optional-evidence summary{font-size:13px;color:var(--blue);cursor:pointer;padding:3px 0}
.optional-evidence .part-answer{margin:10px 0 0}
.optional-evidence .part-answer textarea{min-height:76px}

/* 260911：补充证据保持收起状态，不和当前学习动作争夺注意力。 */
#evidenceTools{margin-top:18px;min-width:0}
.evidence-tools{border-top:1px solid var(--line);padding-top:10px}
.evidence-toggle{appearance:none;display:block!important;width:auto!important;min-height:28px!important;margin:0!important;padding:2px 0!important;border:0!important;background:transparent!important;color:var(--muted)!important;font-size:12px!important;font-weight:400;line-height:1.5;text-align:left;cursor:pointer}
.evidence-toggle::before{content:'＋';display:inline-block;width:18px;color:var(--blue);font-size:15px;line-height:1;vertical-align:-1px}
.evidence-toggle[aria-expanded="true"]::before{content:'−'}
.evidence-toggle:hover{color:var(--blue)!important}
.evidence-toggle:focus-visible{outline:3px solid #79a8d7;outline-offset:3px}
.evidence-tools-body{display:grid;gap:8px;margin-top:10px}
.evidence-note{display:block;width:100%;min-height:76px;resize:vertical;padding:8px 10px;border:1px solid #c9d8e6;border-radius:6px;background:var(--paper);color:var(--ink);font-size:13px;line-height:1.55}
.evidence-note::placeholder{color:#8a98a6}
.evidence-note:focus{border-color:#8eafce;outline:3px solid rgba(121,168,215,.22);outline-offset:1px}
.evidence-capture-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}
.evidence-mode-button{appearance:none;display:inline-flex!important;align-items:center;justify-content:center;width:100%!important;min-height:40px!important;margin:0!important;padding:8px 10px!important;border:1px solid #b9cfe3!important;border-radius:6px!important;background:#f7fbff!important;color:var(--blue)!important;font-size:13px!important;font-weight:600;line-height:1.35;text-align:center;text-decoration:none;transition:background-color .15s,border-color .15s,transform .05s}
.evidence-mode-button:hover{background:var(--tint)!important;border-color:#8eafce!important}
.evidence-mode-button:active{transform:translateY(1px)}
.evidence-mode-button:focus-visible{outline:3px solid #79a8d7;outline-offset:2px}
.evidence-mode-button.has-file{background:var(--tint)!important;border-color:#8eafce!important}
.evidence-mode-button.is-recording{background:#fff0ed!important;border-color:#c96c5b!important;color:#a54a3b!important;box-shadow:0 0 0 3px rgba(201,108,91,.14)}
.evidence-file-input{position:absolute!important;width:1px!important;height:1px!important;overflow:hidden!important;clip:rect(0 0 0 0)!important;white-space:nowrap!important;clip-path:inset(50%)!important}
.evidence-tools button{width:100%;min-height:36px;font-size:13px}
.evidence-tools .evidence-submit{appearance:none;display:block!important;width:100%!important;min-height:40px!important;margin:2px 0 0!important;padding:8px 10px!important;border:1px solid var(--blue)!important;border-radius:6px!important;background:var(--blue)!important;color:#fff!important;font-size:13px!important;font-weight:600;line-height:1.35;text-align:center;transition:background-color .15s,border-color .15s,transform .05s}
.evidence-tools .evidence-submit:hover{background:#224d7c!important;border-color:#224d7c!important}
.evidence-tools .evidence-submit:active{transform:translateY(1px)}
.evidence-tools .evidence-submit:focus-visible{outline:3px solid #79a8d7;outline-offset:2px}
.evidence-tools audio{width:100%;height:34px}
.evidence-status{min-height:0;margin:0;color:var(--muted);font-size:12px;line-height:1.5;overflow-wrap:anywhere}
.evidence-status:empty{display:none}
.evidence-status[data-error="true"]{color:#a4513d}
.preference-intro{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;margin:4px 0 24px;padding-bottom:16px;border-bottom:1px solid var(--line)}
.preference-intro h2{margin:0 0 4px;font-size:20px;color:var(--ink)}
.preference-intro p{margin:0}
.preference-subtitle{display:block;color:var(--muted);font-size:13px}
.preference-progress{flex:0 0 180px;height:6px;background:#e5edf4;border-radius:99px;overflow:hidden}
.preference-progress span{display:block;height:100%;background:var(--blue);border-radius:inherit}
.preference-questions{display:grid;gap:24px}
.preference-question{margin:0;padding-bottom:22px;border-bottom:1px solid var(--line)}
.preference-question-heading{display:flex;align-items:flex-start;gap:12px;margin-bottom:12px}
.preference-question-heading h3{margin:0;font-size:16px;line-height:1.6}
.preference-number{display:grid;place-items:center;flex:0 0 34px;height:28px;color:var(--blue);background:var(--tint);border-radius:5px;font-size:13px;font-weight:700}
.preference-options{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;padding-left:46px}
.preference-option{min-height:92px;padding:13px 15px;text-align:left;background:#fff;border:1px solid var(--line);border-radius:8px;transition:border-color .15s ease,background .15s ease,box-shadow .15s ease}
.preference-option:hover,.preference-option:focus-visible{border-color:#8eafd0;background:#f7fbff}
.preference-option[aria-pressed="true"]{border-color:var(--blue);background:var(--tint);box-shadow:inset 0 0 0 1px var(--blue)}
.preference-option-title{display:block;font-size:15px;font-weight:600;line-height:1.5}
.preference-option small{display:block;margin-top:5px;color:var(--muted);font-size:12px;line-height:1.55}
.preference-note{margin:20px 0 0;color:var(--muted);font-size:13px}
.preference-saved-note{max-width:620px;padding:18px 0 8px}
.preference-saved-note .eyebrow{margin:0 0 10px;color:var(--blue);font-size:13px;font-weight:700}
.preference-saved-note p:last-child{margin:0;color:var(--muted);font-size:15px;line-height:1.8}
.preference-summary{max-width:760px}
.preference-summary h2,.preference-setting h2{margin:0 0 12px;font-size:24px;line-height:1.45}
.preference-overview{max-width:680px;margin:0;color:var(--ink);font-size:16px;line-height:1.8}
.preference-summary-subtitle{margin:0 0 12px;color:var(--muted);font-size:14px;line-height:1.6}
.preference-summary-section{margin-top:30px}
.preference-summary-section h3{margin:0 0 14px;font-size:16px}
.preference-summary-cards{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}
.preference-summary-card{padding:15px 16px;border:1px solid var(--line);border-radius:8px;background:#fff}
.preference-summary-card h4{margin:0 0 6px;color:var(--blue);font-size:15px}
.preference-summary-card p{margin:0;color:var(--muted);font-size:13px;line-height:1.65}
.preference-presentation{margin:0;color:var(--ink);font-size:15px;line-height:1.7}
.preference-context-notes{padding:14px 16px;border:1px solid #d5e3ef;border-radius:8px;background:#f7fafc}
.preference-context-notes h3{margin-bottom:8px}
.preference-context-notes p{margin:0;color:var(--ink);font-size:14px;line-height:1.75}
.preference-context-notes ul{margin:0;padding:0;list-style:none}
.preference-context-notes li{padding:10px 0;border-top:1px solid #dce7f1}
.preference-context-notes li:first-child{border-top:0}
.preference-context-notes li strong{display:block;color:var(--blue);font-size:13px}
.preference-context-notes li span{display:block;color:var(--ink);font-size:14px;line-height:1.75}
.preference-test-explanation{padding-top:4px}
.preference-test-explanation>p{max-width:700px;color:var(--muted);font-size:14px;line-height:1.8}
.preference-test-dimensions{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px 24px;margin:8px 0 16px;padding:0;list-style:none;color:var(--ink);font-size:14px}
.preference-test-dimensions li{padding:8px 10px;border-left:3px solid #c7d9e9;background:#f7fafc}
.preference-state-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px;margin-top:18px}
.preference-state-grid article{padding:13px 14px;border:1px solid var(--line);border-radius:7px;background:#fff}
.preference-state-grid h4{margin:0 0 5px;color:var(--blue);font-size:14px}
.preference-state-grid p{margin:0;color:var(--muted);font-size:12px;line-height:1.65}
.preference-dynamic-note{margin:28px 0 0;padding-top:18px;border-top:1px solid var(--line);color:var(--muted);font-size:13px;line-height:1.8}
.preference-setting{max-width:760px}
.preference-setting .eyebrow{margin:0 0 10px;color:var(--blue);font-size:13px;font-weight:700}
.preference-setting-hint{margin:0 0 22px;color:var(--muted);font-size:14px;line-height:1.7}
.preference-choice .preference-option-title{font-size:14px}
.preference-choice[aria-pressed="true"]{border-color:var(--blue);background:var(--tint);box-shadow:inset 0 0 0 1px var(--blue)}
.preference-nav-steps{display:grid;gap:7px;margin:0;padding:0;list-style:none;color:var(--muted);font-size:12px}
.preference-nav-steps li{display:flex;align-items:center;gap:8px;padding:4px 0}
.preference-nav-steps li span{display:grid;place-items:center;width:20px;height:20px;border-radius:50%;background:#eaf1f8;color:var(--muted);font-size:11px}
.preference-nav-steps li.is-current{color:var(--blue);font-weight:600}
.preference-nav-steps li.is-current span{background:var(--blue);color:#fff}
.preference-nav-steps li.is-done span{background:#dfeaf5;color:var(--blue)}
.preference-result{max-width:850px}
.preference-result h2{margin:0 0 10px;font-size:22px}
.preference-result-list{list-style:none;padding:0;margin:24px 0;border-top:1px solid var(--line)}
.preference-result-list li{display:grid;grid-template-columns:minmax(0,1fr) minmax(210px,34%);gap:18px;padding:11px 0;border-bottom:1px solid var(--line);font-size:14px}
.preference-result-list strong{color:var(--blue);font-weight:600}
.preference-nav-progress{cursor:default;color:var(--muted)}
.header-links{display:flex;align-items:center;gap:18px}
.preference-link{font-size:13px;text-decoration:none}
@media(max-width:680px){
  .preference-intro{display:block;margin-bottom:18px}
  .preference-progress{width:100%;margin-top:14px}
  .preference-options{grid-template-columns:1fr;padding-left:0}
  .preference-option{min-height:0}
  .preference-summary-cards{grid-template-columns:1fr}
  .preference-test-dimensions,.preference-state-grid{grid-template-columns:1fr}
  .preference-result-list li{display:block}
  .preference-result-list strong{display:block;margin-top:4px}
  .header-links{gap:10px}
}