The Old NetISSUE #8 of 60

proper nesting · no overlap allowed

Pixel PeteVSQuirks Mode

Pixel Pete saysElements must nest without overlapping — close the inner element before the outer.

XML requires a strict tree: text is valid, but the overlapping text is not. HTML browsers quietly fix overlaps; XHTML parsers reject them. Always close in reverse order of opening — last opened, first closed.

Power-ups you unlock

Strict tree: no overlapping tags
Close in reverse order of opening
Browsers auto-fix overlaps in HTML
XHTML parsers reject them outright

Quirks Mode attacks — common mistakes

Overlapping inline formatting tags
Closing the outer element before the inner
Relying on browser recovery in strict XHTML

Boss battleFix an overlapping / pair so they nest correctly.

Example code

<!doctype html><html><head><meta charset="utf-8"></head>
<body style="background:#06040d;color:#e6e0ff;font-family:monospace;padding:20px"><pre>invalid: &lt;b&gt;&lt;i&gt;x&lt;/b&gt;&lt;/i&gt;
valid:   &lt;b&gt;&lt;i&gt;x&lt;/i&gt;&lt;/b&gt;</pre></body></html>

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