1 <!DOCTYPE html> 2 <html lang="en"> 3 4 <head> 5 <meta charset="UTF-8"> 6 <meta name="viewport" content="width=device-width, initial-scale=1.0"> 7 <meta http-equiv="X-UA-Compatible" content="ie=edge"> 8 <meta name="author" content="杨欣"> 9 <title>css三角形</title> 10 <style> 11 .triangle{ 12 width: 0; 13 height: 0; 14 border-width: 40px; 15 border-style: solid; 16 border-color: transparent transparent transparent red; 17 /*border-color的四个值代表上右下左，分别实现下左上右箭头 */ 18 } 19 </style> 20 </head> 21 22 <body> 23 <div class="triangle"></div> 24 </body> 25 26 </html>
