#txtList { font-size:14px; height:20px; border-bottom:none; } #txtResult { font-size:16px; font-weight:bold; color:dimgray; height:30px; border-top:none; } .calc-inner { margin:0 auto; border:1px solid darkgray; width:280px; padding:8px; } .result,.op-number { margin:0 auto; width:280px; } .result>input { width:280px; text-align:right; border:1px solid gray; display:block; padding-right:6px; box-sizing:border-box; } ul,li { margin:0; padding:0; } li { list-style:none; } .op-number { margin-top:10px; } .op-number li { float:left; padding:5px; } .op-number>ul::after { content:""; display:block; height:0; overflow:hidden; font-size:0; clear:both; } .op-number li>input { width:60px; height:42px; line-height:28px; }