3 methods: 1. Use the text-align attribute to set "text-align: center;" to the parent element containing img. 2. Use the flexible box layout and set "display: flex;justify-content: center;" to the parent element. 3. Use grid layout and set "display:grid;align-items:center;justify-items:center;" to the parent element.
The operating environment of this tutorial: Windows 7 system, CSS3&&HTML5 version, Dell G3 computer.
Method 1: Use the text alignment attribute text-align
text-align to control the alignment of text lines in the element. You can set a parent div for img, so that img can be the text of the div, and then use text-align to modify the div attributes. (Add attributes to the parent element)
Note: The child element must be inline or inline-block; if the child element is also a div, you need to set display: inline/inline-block for the child element. Here the child element img is inline so omit this step. This method is suitable for inline elements, such as the centering of img
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <style> #pic { border: 1px solid red; text-align: center; /*表示div的子元素居中*/ } </style> </head> <body> <div id="pic"> <img src="img/2.jpg" class="logo" alt="Img in css does not know the width and height, how to achieve centering" > </div> </body> </html>
Method 2: Use flexible box layout
css
#pic { display: flex; justify-content: center; }
Flexible box layout can achieve almost any layout using a few lines of css. And the most amazing thing is that even the top two rows of n pictures can be centered, without having to consider the picture layout and position.
Method 3: Using grid layout
Flexible boxes are most commonly used in navigation bars. In contrast, grid layout is a universal layout system.
#pic { display: grid; align-items: center; /*块级方向(纵向)上的全部栅格元素居中对齐*/ justify-items: center; /*行内方向(横向)所有的元素中线对齐*/ }
#So it is very convenient to deal with the problem of aligning multiple pictures.
(Learning video sharing: web front-end)
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