<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>Document</title> <style> .banner { position: relative; margin: 0 auto; width: 1226px; height: 600px; } .mask { position: absolute; left: 0; bottom: 0; /* 绝对定位的盒子显示模式具备行内块特点: 加宽度高度生效, 如果没有宽度也没有内容, 盒子的宽度尺寸就是0 */ /* width: 1226px; */ /* 如果子级和父级的宽度相同 */ width: 100%; height: 150px; background-color: rgba(0,0,0, .5); } </style> </head> <body> <div class="banner"> <img src="./images/bg.jpg" alt=""> <!-- 遮罩 --> <div class="mask">111</div> </div> </body> </html>
