html { font-family: sans-serif; line-height: 1.4; overflow-wrap: break-word; }
body { margin: 0 auto; max-width: 40rem; padding: 1rem; }
figure { margin: 1.5rem 0; padding: 0; }
figcaption { margin-top: 0.5rem; }
.screen { background: #ccc; border: 2px solid #777; padding: 0.5rem; }
.bar { font-weight: bold; }
.box { background: #e6e6e6; border: 1px solid #999; padding: 0.4rem; margin-top: 0.4rem; }
.box .box { background: #f2f2f2; }
.cols { display: flex; flex-wrap: wrap; gap: 0.4rem; }
.cols > .box { flex: 1 1 10rem; }
.out { border-style: dashed; border-width: 2px; }
.tree, .tree ul { list-style: none; margin: 0; padding-inline-start: 1.25rem; border-inline-start: 1px solid #999; }
.tree { padding-inline-start: 0; border: 0; }
.tree li { margin: 0.2rem 0; }