练习题5_响应式布局-图片优化.html 2.8 KB

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  1. <!DOCTYPE html>
  2. <html lang="en">
  3. <head>
  4. <meta charset="UTF-8">
  5. <meta name="viewport" content="width=device-width, initial-scale=1.0">
  6. <title>Document</title>
  7. <style>
  8. body{
  9. margin: 0;
  10. }
  11. figure{
  12. margin: 0;
  13. }
  14. .container{
  15. max-width: 980px;
  16. margin: 0 auto;
  17. }
  18. header,nav,footer{
  19. height: 50px;
  20. background-color:#ccc;
  21. font-size: 20px;
  22. text-align: center;
  23. line-height: 50px;
  24. font-weight: bolder;
  25. margin-bottom: 20px;
  26. }
  27. figure .bg-img{
  28. background-image: url("./img/1.jpg");
  29. background-size: contain;
  30. background-repeat: no-repeat;
  31. width: 100%;
  32. padding-bottom: 56%;
  33. }
  34. .content{
  35. display: flex;
  36. justify-content: space-between;
  37. margin: 20px 0;
  38. }
  39. .content article{
  40. background-color: chocolate;
  41. /* flex-grow:3; */
  42. width: 60%;
  43. }
  44. .content aside{
  45. background-color: palegreen;
  46. width: 38%;
  47. /* flex-grow: 1; */
  48. }
  49. @media screen and (min-width:480px) and (max-width:960px) {
  50. .container figure .bg-img{
  51. background-image: url("./img/2.jpg");
  52. }
  53. }
  54. @media screen and (max-width:480px) {
  55. .container figure .bg-img{
  56. background-image: url("./img/3.jpg");
  57. }
  58. .content{
  59. /* display: block; */
  60. flex-direction: column;
  61. }
  62. .content article,.content aside{
  63. width: 100%;
  64. margin-top: 20px;
  65. }
  66. }
  67. </style>
  68. </head>
  69. <body>
  70. <div class="container">
  71. <header>页头</header>
  72. <nav>导航</nav>
  73. <figure>
  74. <div class="bg-img"></div>
  75. <!-- <img src="./img/1.jpg" alt="img">
  76. <img src="./img/2.jpg" alt="img">
  77. <img src="./img/3.jpg" alt="img"> -->
  78. </figure>
  79. <div class="content">
  80. <article>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris sem erat, egestas quis luctus ut, rhoncus vitae risus. Integer venenatis libero sit amet sapien dictum, quis bibendum mi volutpat. Cras pretium quam quis magna facilisis, eget feugiat nisi lacinia.</article>
  81. <aside>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Mauris sem erat, egestas quis luctus ut, rhoncus vitae risus. Integer venenatis libero sit amet sapien dictum, quis bibendum mi volutpat. Cras pretium quam quis magna facilisis, eget feugiat nisi lacinia.</aside>
  82. </div>
  83. <footer>页脚</footer>
  84. </div>
  85. </body>
  86. </html>