css3语法: (750px设计图的1rem = 100px) @media only screen and (min-width: 320px) and (max-width: 479px){ html { font-size: 42.67px !important; } } @media only screen and (min-width: 480px) and (max-width: 639px){ html { font-size: 64px !important; } } @media only screen and
