使用css3中的rgba:
r: red,取正整数或者百分数;
g:green,取正整数或者百分数;
b:blue,取正整数或者百分数;
a:alpha,取0~1之间的数
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>css3的rgba</title> <style> *{ padding: 0; margin: 0; } body{ padding: 50px; } .mydemo{ padding: 25px; background-color: red; background-color:rgba(255,0,0,0.5); } .mydemo p{ color: black; } </style> </head> <body> <div class="mydemo"> <p>myIp</p> </div> </html>