只显示下边框的Text.(

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原理可以是隐藏其他3个方向的边框:

<DIV align=center >
只有下边框：<INPUT style="BORDER-RIGHT: medium none; BORDER-TOP: medium none; BORDER-LEFT: medium none; COLOR: rgb(255,0,0); BORDER-BOTTOM: rgb(192,192,192) 1px solid" name=answer>
</DIV>