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<html><head><style>[class|=top] { background: yellow;}</style></head><body><h1>Demo of the [attribute|=value] selector</h1><p>Elements with a class attribute value of "top" or "top-" is styled with a yellow background:</p><h1 class="top-header">Welcome</h1><p class="top-text">Hello world!</p><p class="topcontent">Are you learning CSS?</p></body></html>