可以是属性值,也可以是具体的一些值
<!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> .container { width: 200px; height: 200px; background-color: bisque; } img { width: 20px; height: 20px; /* 使行内元素盒模型与其行内元素容器垂直对齐。例如,用于垂直对齐一行文本内的图片<img>: */ vertical-align: middle; } </style> </head> <body> <div class="container"> <span>更上一层楼</span> <img src="./dino.svg" alt=""> </div> </body> </html>