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/* Readable classroom labels, including narrow displays. */
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.extension-notice{position:absolute;top:52px;left:12px;right:12px;z-index:2;max-width:340px;margin:auto;padding:11px 14px;text-align:center;border:1px solid #a9c6ff;border-radius:10px;background:#eff6fff5;box-shadow:0 5px 20px #3c6bc21a;color:#245bb0;pointer-events:none;opacity:0;visibility:hidden}.extension-notice strong{display:block;font-size:14px}.extension-notice span{display:block;font-size:12px;line-height:1.6;margin-top:4px}.extension-notice.show{animation:container-extension 3.6s ease-in-out forwards}@keyframes container-extension{0%{opacity:0;visibility:visible;transform:translateY(6px)}12%,36%,62%,78%{opacity:1;visibility:visible;transform:translateY(0)}24%,49%{opacity:.35;visibility:visible}99%{visibility:visible}100%{opacity:0;visibility:hidden;transform:translateY(-4px)}}

.chamber-caption{flex-wrap:wrap;gap:6px 10px}#thermal-activity{font-size:11px;color:#6785b0;flex-basis:100%;padding-left:2px}

/* Teacher Li's cheerful flask identity. */
.brand{font-size:19px;letter-spacing:.3px;flex-shrink:0}.brand-mark{display:block;width:52px;height:52px;background:transparent;border-radius:0;flex-shrink:0}.brand-en{font-size:11px;letter-spacing:1.8px;font-weight:500;color:#8499ad;margin-top:6px}.lab-label{white-space:nowrap}@media(max-width:650px){.site-header{gap:12px}.brand{font-size:15px;gap:8px}.brand-mark{width:44px;height:44px}.brand-en{font-size:10px;letter-spacing:1px;margin-top:5px}.lab-label{font-size:10px;padding:6px 8px}}@media(max-width:390px){.site-header .lab-label{display:none}}