@charset "UTF-8";
.lesson { display: grid; gap: var(--gap); grid-template-columns: minmax(0, 1fr) 260px; align-items: start; }
.lesson__toc { position: sticky; top: 96px; }
.lesson__toc ol { list-style: none; padding: 0; margin: 0; display: grid; gap: 4px; font-size: .92rem; }
.lesson__toc a { display: block; padding: 6px 10px; border-radius: 10px; color: var(--muted); text-decoration: none; }
.lesson__toc a:hover { color: var(--accent); box-shadow: var(--inset-sm); }
@media (max-width: 960px) { .lesson { grid-template-columns: 1fr; } .lesson__toc { position: static; order: -1; } }

.lesson__meta { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 1.2em; }

.demo { border-radius: var(--radius); box-shadow: var(--raised-sm); padding: 20px; margin: 0 0 1.2em; }
.demo__label { display: block; font-size: .75rem; font-weight: 700; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); margin-bottom: 10px; }

.lesson-nav { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 14px; margin-top: 2em; }

/* Демо урока про div и span */
.ds-strong { font-weight: 700; color: var(--danger); }
.ds-em { font-style: italic; color: var(--accent); }
.ds-mark { background: #ffe066; color: #1f2a3a; padding: 0 4px; border-radius: 4px; }
.ds-s { text-decoration: line-through; }
.ds-red { color: #e5484d; }
.ds-big { font-size: 1.2em; }
.ds-mono { font-family: var(--mono); }
.ds-button { display: inline-block; padding: 8px 16px; margin: 4px 6px 4px 0; border-radius: 12px; box-shadow: var(--raised-sm); cursor: pointer; font-weight: 600; user-select: none; }
.ds-button:active { box-shadow: var(--inset-sm); }
.ds-hidden { display: none; margin-top: 10px; padding: 12px; border-radius: 12px; box-shadow: var(--inset-sm); }
.ds-hidden.is-visible { display: block; }
.ds-input { display: block; min-height: 44px; padding: 10px 14px; border-radius: 12px; box-shadow: var(--inset-sm); margin: 6px 0; }
.ds-error { color: var(--danger); font-size: .9rem; }
.ds-success { color: var(--success); font-weight: 600; }
.ds-tooltip { position: relative; border-bottom: 1px dotted var(--accent); cursor: help; }
.ds-tooltip__text { position: absolute; bottom: 130%; left: 50%; transform: translateX(-50%); width: 220px; padding: 8px 10px; border-radius: 10px; background: var(--text); color: var(--bg); font-size: .85rem; text-align: center; opacity: 0; visibility: hidden; transition: opacity .2s; }
.ds-tooltip:hover .ds-tooltip__text, .ds-tooltip:focus .ds-tooltip__text { opacity: 1; visibility: visible; }
@keyframes ds-flash { 50% { background: #ffe066; color: #1f2a3a; } }
.ds-flash { animation: ds-flash 1.6s; border-radius: 4px; }
.ds-tabs { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 10px; }
.ds-tab.is-active { box-shadow: var(--inset-sm); color: var(--accent); }
.ds-panel { display: none; padding: 12px; border-radius: 12px; box-shadow: var(--inset-sm); }
.ds-panel.is-active { display: block; }
.ds-table { display: table; width: 100%; border-collapse: collapse; }
.ds-row { display: table-row; }
.ds-cell { display: table-cell; padding: 8px 10px; border-bottom: 1px solid color-mix(in srgb, var(--shadow-dark) 60%, transparent); }
.ds-row:first-child .ds-cell { font-weight: 700; }

/* Демо урока про кодировку CSS */
.enc-demo::before { content: "Это текст из ::before → "; color: var(--accent); font-weight: 700; }
.enc-demo::after { content: " ← а это из ::after"; color: var(--accent); font-weight: 700; }
.lesson-nav a:first-child svg { transform: scaleX(-1); }