Tips - CSS Layout

*{margin: 0px;} // 去缝隙
header_t_l{... float:left;} // 对齐方式
header_t_r{... float:left;} // 用display:inline?
header_b{... float:left;}  // (?)<div>是block级别的
@reference_1

The Old Way - using {float: left;}{clear: left;}
The New Way - using {display: inline-block;}

@reference_2

...CSS box model中，width/height不算入padding和border...

@reference_3

img{vertical-align:middle;} //图片和input输入框水平对齐