:root{--ink:#232426;--muted:#777b82;--line:#e7e8eb;--blue:#0071e3;--bg:#f5f5f7;--m1:#526b7b;--m2:#766b80;--m3:#647d68}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:14px/1.65 -apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei",sans-serif}button,input,select,textarea{font:inherit}button,a,input,select,textarea{-webkit-tap-highlight-color:transparent}button{border:1px solid var(--line);border-radius:12px;padding:8px 16px;background:#fff;color:var(--ink);cursor:pointer}button:hover{background:#f2f3f5}button:disabled{opacity:.5;cursor:wait}button:focus-visible,a:focus-visible,input:focus-visible,select:focus-visible,textarea:focus-visible{outline:3px solid 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.outline-group{padding:16px 0;border-bottom:1px solid var(--line)}.outline-group summary{cursor:pointer;font-weight:600;line-height:1.8}.outline-group .inspector-list{padding-top:16px}.outline-group summary:focus-visible{outline:2px solid #0071e3;outline-offset:4px}
.assistant{width:640px;max-width:calc(100vw - 32px);height:calc(100dvh - 32px);max-height:1000px;top:16px;bottom:auto;display:flex;flex-direction:column}.assistant[hidden]{display:none}.assistant>header,.assistant>.ai-controls,.assistant>.ai-toolbar,.assistant>#ai-context,.assistant>.ai-settings-panel,.assistant>#ai-prompt-hint,.assistant>form,.assistant>.footnote{flex-shrink:0}.assistant .messages{flex:1;min-height:100px;max-height:none;overflow:auto}.ai-toolbar{display:flex;gap:8px;padding:0 20px 8px}.ai-toolbar button{font-size:12px;padding:4px 12px}.ai-settings-panel{margin:0 20px 8px;max-height:220px;overflow:auto}.ai-settings-panel summary{color:var(--muted);font-size:12px}.ai-setting-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.ai-settings-panel label{display:block;font-size:12px;margin:8px 0}.ai-settings-panel select,.ai-settings-panel input{display:block;width:100%;min-width:0;border:1px solid var(--line);border-radius:8px;padding:8px;background:#fff}.assistant #ai-prompt-hint{font-size:12px;padding:0 20px;margin:0 0 8px}.assistant #ai-context{margin:0 20px 8px;padding:8px 12px;font-size:12px}.assistant .message{overflow-wrap:anywhere}.assistant .message h3{margin:12px 0 4px}.assistant .message pre{white-space:pre-wrap}.assistant .message code{background:#eef0f3;border-radius:4px;padding:0 4px}.assistant .message math{font-size:1.1em;max-width:100%;overflow:auto}.assistant .message math[display="block"]{display:block;margin:12px 0}.ai-resource-links{display:grid;gap:8px}.ai-answer-actions{display:flex;flex-wrap:wrap;gap:12px;margin-top:12px}.ai-answer-actions button{font-size:12px}.ai-error{border:1px solid #d4b9aa!important;color:#805238}.ai-page-actions{display:flex;gap:12px;justify-content:flex-end;margin-bottom:20px}.assistant #chat-form{padding:12px 20px}.assistant #chat-form textarea{min-height:72px;max-height:120px}.assistant .footnote{padding:0 20px 12px;margin:0;font-size:11px}@media(max-width:600px){.assistant{top:8px;right:8px;max-width:calc(100vw - 16px);height:calc(100dvh - 16px);border-radius:20px}.ai-setting-grid{grid-template-columns:1fr}.ai-settings-panel{max-height:180px}.assistant .ai-controls{flex-wrap:wrap}.ai-page-actions{justify-content:flex-start;flex-wrap:wrap}}
.ai-table{overflow-x:auto;white-space:normal;margin:12px 0}.ai-table table{border-collapse:collapse;width:100%;font-size:12px}.ai-table th,.ai-table td{padding:8px;border:1px solid var(--line);vertical-align:top;min-width:64px}.ai-table th{background:#edf0f3}.ai-table td:last-child{min-width:120px}

/* Compact everyday chat; teaching parameters live in their own dialog. */
#assistant [hidden]{display:none!important}#assistant header>div{flex:1}#assistant header{gap:12px}#assistant .messages{min-height:120px}#chat-form{display:flex;flex-direction:column;gap:12px}#chat-form textarea{width:100%;min-height:96px} .ai-input-actions{display:flex;align-items:center;gap:8px}.ai-input-actions small{flex:1;color:var(--muted,#737780);font-size:12px}#ai-tool-settings{padding:16px 0}#assistant .footnote{margin:0;padding:0 16px 12px}