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@media(max-width:420px){.topbar{align-items:flex-start;flex-direction:column}.nav{width:100%}.brand{white-space:nowrap}}
.lesson{padding:14px 0;border-top:1px solid #e0e9e0}.lesson summary{cursor:pointer;line-height:1.6;font-weight:700;min-height:44px}.lesson li{line-height:1.8;margin-bottom:8px}
.notebook-title{cursor:pointer;font-size:19px;font-weight:750;min-height:44px;line-height:1.8}
[hidden] { display: none !important; }
.history-row { flex-wrap: wrap; gap: 10px; }
.history-row .actions { margin-top: 0; flex-wrap: wrap; }
.history-answer { padding: 12px 0; border-bottom: 1px solid #e4e7ec; overflow-wrap: anywhere; }