{"id":177,"date":"2024-12-12T23:18:03","date_gmt":"2024-12-12T15:18:03","guid":{"rendered":"https:\/\/www.laixuexila.com\/?p=177"},"modified":"2024-12-12T23:18:03","modified_gmt":"2024-12-12T15:18:03","slug":"css-%e9%80%89%e6%8b%a9%e5%99%a8%ef%bc%9a%e4%bb%8e%e5%88%9d%e5%ad%a6%e8%80%85%e5%88%b0%e4%b8%93%e5%ae%b6%e7%9a%84%e5%ae%8c%e6%95%b4%e6%8c%87%e5%8d%97","status":"publish","type":"post","link":"https:\/\/www.laixuexila.com\/index.php\/2024\/12\/12\/css-%e9%80%89%e6%8b%a9%e5%99%a8%ef%bc%9a%e4%bb%8e%e5%88%9d%e5%ad%a6%e8%80%85%e5%88%b0%e4%b8%93%e5%ae%b6%e7%9a%84%e5%ae%8c%e6%95%b4%e6%8c%87%e5%8d%97\/","title":{"rendered":"CSS \u9009\u62e9\u5668\uff1a\u4ece\u521d\u5b66\u8005\u5230\u4e13\u5bb6\u7684\u5b8c\u6574\u6307\u5357"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">CSS \u9009\u62e9\u5668\u662f\u524d\u7aef\u5f00\u53d1\u4e2d\u7684\u57fa\u7840\u548c\u6838\u5fc3\uff0c\u7528\u4e8e\u9009\u62e9 HTML \u5143\u7d20\u5e76\u5e94\u7528\u6837\u5f0f\u3002\u4ee5\u4e0b\u6307\u5357\u4ece\u57fa\u7840\u5230\u9ad8\u7ea7\u9010\u6b65\u8bb2\u89e3 CSS \u9009\u62e9\u5668\uff0c\u5e2e\u52a9\u4f60\u5168\u9762\u638c\u63e1\u8fd9\u4e00\u6280\u80fd\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e00\u3001\u57fa\u7840\u9009\u62e9\u5668\uff08\u521d\u5b66\u8005\u9636\u6bb5\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u901a\u7528\u9009\u62e9\u5668\uff08<code>*<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5339\u914d\u6240\u6709\u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>* {\n  margin: 0;\n  padding: 0;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u7c7b\u578b\u9009\u62e9\u5668\uff08\u6807\u7b7e\u9009\u62e9\u5668\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u7279\u5b9a\u7684 HTML \u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>p {\n  color: blue;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u7c7b\u9009\u62e9\u5668\uff08<code>.classname<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u5177\u6709\u7279\u5b9a\u7c7b\u7684\u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>.card {\n  background-color: #f9f9f9;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">4. <strong>ID \u9009\u62e9\u5668\uff08<code>#id<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u5177\u6709\u7279\u5b9a ID \u7684\u5143\u7d20\uff08\u5c3d\u91cf\u5c11\u7528\uff09\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#header {\n  height: 60px;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">5. <strong>\u5206\u7ec4\u9009\u62e9\u5668\uff08<code>,<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3a\u591a\u4e2a\u5143\u7d20\u5e94\u7528\u76f8\u540c\u6837\u5f0f\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1, h2, h3 {\n  font-weight: bold;\n}<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e8c\u3001\u7ec4\u5408\u9009\u62e9\u5668\uff08\u8fdb\u9636\u9636\u6bb5\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u540e\u4ee3\u9009\u62e9\u5668\uff08<code>A B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9 A \u5143\u7d20\u5185\u7684\u6240\u6709 B \u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>div p {\n  color: gray;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u5b50\u9009\u62e9\u5668\uff08<code>A &gt; B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9 A \u5143\u7d20\u7684\u76f4\u63a5\u5b50\u5143\u7d20 B\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>ul &gt; li {\n  list-style: none;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u76f8\u90bb\u5144\u5f1f\u9009\u62e9\u5668\uff08<code>A + B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u7d27\u63a5\u5728 A \u5143\u7d20\u540e\u7684\u5144\u5f1f\u5143\u7d20 B\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1 + p {\n  font-size: 14px;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">4. <strong>\u901a\u7528\u5144\u5f1f\u9009\u62e9\u5668\uff08<code>A ~ B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9 A \u5143\u7d20\u540e\u6240\u6709\u5144\u5f1f B \u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1 ~ p {\n  color: #888;\n}<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e09\u3001\u5c5e\u6027\u9009\u62e9\u5668\uff08\u9ad8\u6548\u7b5b\u9009\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u57fa\u672c\u5c5e\u6027\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr]<\/code>\uff1a\u5177\u6709\u67d0\u5c5e\u6027\u7684\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  &#91;disabled] {\n    opacity: 0.5;\n  }<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u57fa\u4e8e\u5c5e\u6027\u503c\u7684\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u5b8c\u5168\u5339\u914d\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  input&#91;type=\"text\"] {\n    border: 1px solid #ccc;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr~=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u5305\u542b\u6307\u5b9a\u5355\u8bcd\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  &#91;class~=\"button\"] {\n    padding: 10px;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr|=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u4ee5\u6307\u5b9a\u503c\u5f00\u5934\uff0c\u540e\u53ef\u8ddf\u8fde\u5b57\u7b26\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  &#91;lang|=\"en\"] {\n    font-style: italic;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr^=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u4ee5\u6307\u5b9a\u503c\u5f00\u5934\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  a&#91;href^=\"https\"] {\n    color: green;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr$=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u4ee5\u6307\u5b9a\u503c\u7ed3\u5c3e\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  img&#91;src$=\".jpg\"] {\n    border-radius: 5px;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr*=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u5305\u542b\u6307\u5b9a\u503c\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  a&#91;href*=\"example\"] {\n    text-decoration: underline;\n  }<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u56db\u3001\u4f2a\u7c7b\u9009\u62e9\u5668\uff08\u52a8\u6001\u6837\u5f0f\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u5e38\u89c1\u52a8\u6001\u4f2a\u7c7b<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:hover<\/code>\uff1a\u9f20\u6807\u60ac\u505c\u65f6\u89e6\u53d1\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  button:hover {\n    background-color: #ddd;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:focus<\/code>\uff1a\u5143\u7d20\u83b7\u53d6\u7126\u70b9\u65f6\u89e6\u53d1\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  input:focus {\n    outline: 2px solid blue;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:active<\/code>\uff1a\u5143\u7d20\u88ab\u6fc0\u6d3b\u65f6\u89e6\u53d1\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  a:active {\n    color: red;\n  }<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u7ed3\u6784\u6027\u4f2a\u7c7b<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:nth-child(n)<\/code>\uff1a\u9009\u62e9\u7236\u5143\u7d20\u4e2d\u7b2c n \u4e2a\u5b50\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  li:nth-child(2) {\n    color: red;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:nth-last-child(n)<\/code>\uff1a\u9009\u62e9\u5012\u6570\u7b2c n \u4e2a\u5b50\u5143\u7d20\u3002<\/li>\n\n\n\n<li><code>:first-child<\/code> \/ <code>:last-child<\/code>\uff1a\u7b2c\u4e00\u4e2a\/\u6700\u540e\u4e00\u4e2a\u5b50\u5143\u7d20\u3002<\/li>\n\n\n\n<li><code>:only-child<\/code>\uff1a\u552f\u4e00\u5b50\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u76ee\u6807\u4f2a\u7c7b<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:target<\/code>\uff1a\u5339\u914d\u5f53\u524d URL \u6307\u5b9a\u7684\u76ee\u6807\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  #section1:target {\n    background-color: yellow;\n  }<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e94\u3001\u4f2a\u5143\u7d20\uff08\u9ad8\u7ea7\u7f8e\u5316\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <code>::before<\/code> \u548c <code>::after<\/code><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u7528\u4e8e\u5728\u5143\u7d20\u524d\u540e\u63d2\u5165\u5185\u5bb9\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1::before {\n  content: \"\u2605\";\n  color: gold;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <code>::first-letter<\/code> \u548c <code>::first-line<\/code><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3a\u6bb5\u843d\u9996\u5b57\u6bcd\u6216\u9996\u884c\u8bbe\u7f6e\u6837\u5f0f\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>p::first-letter {\n  font-size: 2em;\n  font-weight: bold;\n}<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u516d\u3001\u4f18\u5148\u7ea7\u4e0e\u5c42\u53e0\u89c4\u5219<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u9009\u62e9\u5668\u4f18\u5148\u7ea7<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5185\u8054\u6837\u5f0f\uff1a<code>style=\"\"<\/code>\uff08\u4f18\u5148\u7ea7\u6700\u9ad8\uff09<\/li>\n\n\n\n<li>ID \u9009\u62e9\u5668\uff1a<code>#id<\/code><\/li>\n\n\n\n<li>\u7c7b\u3001\u5c5e\u6027\u9009\u62e9\u5668\u3001\u4f2a\u7c7b\uff1a<code>.class<\/code>\u3001<code>[attr]<\/code>\u3001<code>:hover<\/code><\/li>\n\n\n\n<li>\u5143\u7d20\u9009\u62e9\u5668\u548c\u4f2a\u5143\u7d20\uff1a<code>p<\/code>\u3001<code>::before<\/code><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u6743\u91cd\u8ba1\u7b97<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f18\u5148\u7ea7\u7531\u6743\u91cd\u51b3\u5b9a\uff0c\u89c4\u5219\u5982\u4e0b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5185\u8054\u6837\u5f0f\uff1a1000<\/li>\n\n\n\n<li>ID \u9009\u62e9\u5668\uff1a100<\/li>\n\n\n\n<li>\u7c7b\u9009\u62e9\u5668\uff1a10<\/li>\n\n\n\n<li>\u5143\u7d20\u9009\u62e9\u5668\uff1a1<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f8b\u5982\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* \u6743\u91cd\uff1a10 *\/\n.class {\n  color: red;\n}\n\/* \u6743\u91cd\uff1a100 *\/\n#id {\n  color: blue;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u7ec8 <code>#id<\/code> \u6837\u5f0f\u4f1a\u751f\u6548\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e03\u3001\u7ec4\u5408\u4e0e\u5c42\u53e0\uff08\u4e13\u5bb6\u7ea7\u5e94\u7528\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u7ec4\u5408\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5c06\u9009\u62e9\u5668\u7ec4\u5408\u4ee5\u5b9e\u73b0\u7cbe\u786e\u5339\u914d\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>div#header &gt; ul.menu li:first-child a {\n  color: #333;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u5c42\u53e0\uff08Cascade\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">CSS \u6837\u5f0f\u7684\u5c42\u53e0\u6027\u5141\u8bb8\u591a\u6761\u89c4\u5219\u5e94\u7528\u4e8e\u540c\u4e00\u5143\u7d20\uff0c\u6839\u636e\u4f18\u5148\u7ea7\u548c\u6743\u91cd\u51b3\u5b9a\u6700\u7ec8\u6837\u5f0f\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u903b\u8f91\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528\u4f2a\u7c7b\u548c\u903b\u8f91\u64cd\u4f5c\u5b9e\u73b0\u590d\u6742\u5339\u914d\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:is()<\/code>\uff1a\u5339\u914d\u591a\u4e2a\u9009\u62e9\u5668\u4e4b\u4e00\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  :is(h1, h2, h3) {\n    margin: 0;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:not()<\/code>\uff1a\u6392\u9664\u7279\u5b9a\u9009\u62e9\u5668\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  div:not(.active) {\n    opacity: 0.5;\n  }<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u8fc7\u7cfb\u7edf\u638c\u63e1\u4e0a\u8ff0\u9009\u62e9\u5668\uff0c\u4f60\u53ef\u4ee5\u5728\u9879\u76ee\u4e2d\u9ad8\u6548\u5730\u7b5b\u9009\u3001\u5339\u914d\u5143\u7d20\u5e76\u63a7\u5236\u6837\u5f0f\u3002\u5982\u679c\u9700\u8981\u66f4\u6df1\u5165\u7684\u5b9e\u8df5\u548c\u6848\u4f8b\u5206\u6790\uff0c\u53ef\u4ee5\u7ee7\u7eed\u4ea4\u6d41\uff01<\/p>\n\n\n\n<h3 class=\"wp-block-heading\"><strong>CSS \u9009\u62e9\u5668\uff1a\u4ece\u521d\u5b66\u8005\u5230\u4e13\u5bb6\u7684\u5b8c\u6574\u6307\u5357<\/strong><\/h3>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">CSS \u9009\u62e9\u5668\u662f\u524d\u7aef\u5f00\u53d1\u4e2d\u7684\u57fa\u7840\u548c\u6838\u5fc3\uff0c\u7528\u4e8e\u9009\u62e9 HTML \u5143\u7d20\u5e76\u5e94\u7528\u6837\u5f0f\u3002\u4ee5\u4e0b\u6307\u5357\u4ece\u57fa\u7840\u5230\u9ad8\u7ea7\u9010\u6b65\u8bb2\u89e3 CSS \u9009\u62e9\u5668\uff0c\u5e2e\u52a9\u4f60\u5168\u9762\u638c\u63e1\u8fd9\u4e00\u6280\u80fd\u3002<\/p>\n<\/blockquote>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e00\u3001\u57fa\u7840\u9009\u62e9\u5668\uff08\u521d\u5b66\u8005\u9636\u6bb5\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u901a\u7528\u9009\u62e9\u5668\uff08<code>*<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5339\u914d\u6240\u6709\u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>* {\n  margin: 0;\n  padding: 0;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u7c7b\u578b\u9009\u62e9\u5668\uff08\u6807\u7b7e\u9009\u62e9\u5668\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u7279\u5b9a\u7684 HTML \u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>p {\n  color: blue;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u7c7b\u9009\u62e9\u5668\uff08<code>.classname<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u5177\u6709\u7279\u5b9a\u7c7b\u7684\u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>.card {\n  background-color: #f9f9f9;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">4. <strong>ID \u9009\u62e9\u5668\uff08<code>#id<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u5177\u6709\u7279\u5b9a ID \u7684\u5143\u7d20\uff08\u5c3d\u91cf\u5c11\u7528\uff09\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>#header {\n  height: 60px;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">5. <strong>\u5206\u7ec4\u9009\u62e9\u5668\uff08<code>,<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3a\u591a\u4e2a\u5143\u7d20\u5e94\u7528\u76f8\u540c\u6837\u5f0f\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1, h2, h3 {\n  font-weight: bold;\n}<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e8c\u3001\u7ec4\u5408\u9009\u62e9\u5668\uff08\u8fdb\u9636\u9636\u6bb5\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u540e\u4ee3\u9009\u62e9\u5668\uff08<code>A B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9 A \u5143\u7d20\u5185\u7684\u6240\u6709 B \u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>div p {\n  color: gray;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u5b50\u9009\u62e9\u5668\uff08<code>A &gt; B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9 A \u5143\u7d20\u7684\u76f4\u63a5\u5b50\u5143\u7d20 B\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>ul &gt; li {\n  list-style: none;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u76f8\u90bb\u5144\u5f1f\u9009\u62e9\u5668\uff08<code>A + B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9\u7d27\u63a5\u5728 A \u5143\u7d20\u540e\u7684\u5144\u5f1f\u5143\u7d20 B\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1 + p {\n  font-size: 14px;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">4. <strong>\u901a\u7528\u5144\u5f1f\u9009\u62e9\u5668\uff08<code>A ~ B<\/code>\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u9009\u62e9 A \u5143\u7d20\u540e\u6240\u6709\u5144\u5f1f B \u5143\u7d20\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1 ~ p {\n  color: #888;\n}<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e09\u3001\u5c5e\u6027\u9009\u62e9\u5668\uff08\u9ad8\u6548\u7b5b\u9009\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u57fa\u672c\u5c5e\u6027\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr]<\/code>\uff1a\u5177\u6709\u67d0\u5c5e\u6027\u7684\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  &#91;disabled] {\n    opacity: 0.5;\n  }<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u57fa\u4e8e\u5c5e\u6027\u503c\u7684\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u5b8c\u5168\u5339\u914d\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  input&#91;type=\"text\"] {\n    border: 1px solid #ccc;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr~=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u5305\u542b\u6307\u5b9a\u5355\u8bcd\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  &#91;class~=\"button\"] {\n    padding: 10px;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr|=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u4ee5\u6307\u5b9a\u503c\u5f00\u5934\uff0c\u540e\u53ef\u8ddf\u8fde\u5b57\u7b26\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  &#91;lang|=\"en\"] {\n    font-style: italic;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr^=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u4ee5\u6307\u5b9a\u503c\u5f00\u5934\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  a&#91;href^=\"https\"] {\n    color: green;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr$=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u4ee5\u6307\u5b9a\u503c\u7ed3\u5c3e\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  img&#91;src$=\".jpg\"] {\n    border-radius: 5px;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>[attr*=\"value\"]<\/code>\uff1a\u5c5e\u6027\u503c\u5305\u542b\u6307\u5b9a\u503c\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  a&#91;href*=\"example\"] {\n    text-decoration: underline;\n  }<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u56db\u3001\u4f2a\u7c7b\u9009\u62e9\u5668\uff08\u52a8\u6001\u6837\u5f0f\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u5e38\u89c1\u52a8\u6001\u4f2a\u7c7b<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:hover<\/code>\uff1a\u9f20\u6807\u60ac\u505c\u65f6\u89e6\u53d1\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  button:hover {\n    background-color: #ddd;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:focus<\/code>\uff1a\u5143\u7d20\u83b7\u53d6\u7126\u70b9\u65f6\u89e6\u53d1\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  input:focus {\n    outline: 2px solid blue;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:active<\/code>\uff1a\u5143\u7d20\u88ab\u6fc0\u6d3b\u65f6\u89e6\u53d1\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  a:active {\n    color: red;\n  }<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u7ed3\u6784\u6027\u4f2a\u7c7b<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:nth-child(n)<\/code>\uff1a\u9009\u62e9\u7236\u5143\u7d20\u4e2d\u7b2c n \u4e2a\u5b50\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  li:nth-child(2) {\n    color: red;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:nth-last-child(n)<\/code>\uff1a\u9009\u62e9\u5012\u6570\u7b2c n \u4e2a\u5b50\u5143\u7d20\u3002<\/li>\n\n\n\n<li><code>:first-child<\/code> \/ <code>:last-child<\/code>\uff1a\u7b2c\u4e00\u4e2a\/\u6700\u540e\u4e00\u4e2a\u5b50\u5143\u7d20\u3002<\/li>\n\n\n\n<li><code>:only-child<\/code>\uff1a\u552f\u4e00\u5b50\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u76ee\u6807\u4f2a\u7c7b<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:target<\/code>\uff1a\u5339\u914d\u5f53\u524d URL \u6307\u5b9a\u7684\u76ee\u6807\u5143\u7d20\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  #section1:target {\n    background-color: yellow;\n  }<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e94\u3001\u4f2a\u5143\u7d20\uff08\u9ad8\u7ea7\u7f8e\u5316\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <code>::before<\/code> \u548c <code>::after<\/code><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u7528\u4e8e\u5728\u5143\u7d20\u524d\u540e\u63d2\u5165\u5185\u5bb9\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>h1::before {\n  content: \"\u2605\";\n  color: gold;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <code>::first-letter<\/code> \u548c <code>::first-line<\/code><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4e3a\u6bb5\u843d\u9996\u5b57\u6bcd\u6216\u9996\u884c\u8bbe\u7f6e\u6837\u5f0f\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>p::first-letter {\n  font-size: 2em;\n  font-weight: bold;\n}<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u516d\u3001\u4f18\u5148\u7ea7\u4e0e\u5c42\u53e0\u89c4\u5219<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u9009\u62e9\u5668\u4f18\u5148\u7ea7<\/strong><\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5185\u8054\u6837\u5f0f\uff1a<code>style=\"\"<\/code>\uff08\u4f18\u5148\u7ea7\u6700\u9ad8\uff09<\/li>\n\n\n\n<li>ID \u9009\u62e9\u5668\uff1a<code>#id<\/code><\/li>\n\n\n\n<li>\u7c7b\u3001\u5c5e\u6027\u9009\u62e9\u5668\u3001\u4f2a\u7c7b\uff1a<code>.class<\/code>\u3001<code>[attr]<\/code>\u3001<code>:hover<\/code><\/li>\n\n\n\n<li>\u5143\u7d20\u9009\u62e9\u5668\u548c\u4f2a\u5143\u7d20\uff1a<code>p<\/code>\u3001<code>::before<\/code><\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u6743\u91cd\u8ba1\u7b97<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f18\u5148\u7ea7\u7531\u6743\u91cd\u51b3\u5b9a\uff0c\u89c4\u5219\u5982\u4e0b\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5185\u8054\u6837\u5f0f\uff1a1000<\/li>\n\n\n\n<li>ID \u9009\u62e9\u5668\uff1a100<\/li>\n\n\n\n<li>\u7c7b\u9009\u62e9\u5668\uff1a10<\/li>\n\n\n\n<li>\u5143\u7d20\u9009\u62e9\u5668\uff1a1<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f8b\u5982\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* \u6743\u91cd\uff1a10 *\/\n.class {\n  color: red;\n}\n\/* \u6743\u91cd\uff1a100 *\/\n#id {\n  color: blue;\n}<\/code><\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">\u6700\u7ec8 <code>#id<\/code> \u6837\u5f0f\u4f1a\u751f\u6548\u3002<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e03\u3001\u7ec4\u5408\u4e0e\u5c42\u53e0\uff08\u4e13\u5bb6\u7ea7\u5e94\u7528\uff09<\/h2>\n\n\n\n<h3 class=\"wp-block-heading\">1. <strong>\u7ec4\u5408\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u5c06\u9009\u62e9\u5668\u7ec4\u5408\u4ee5\u5b9e\u73b0\u7cbe\u786e\u5339\u914d\uff1a<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>div#header &gt; ul.menu li:first-child a {\n  color: #333;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">2. <strong>\u5c42\u53e0\uff08Cascade\uff09<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">CSS \u6837\u5f0f\u7684\u5c42\u53e0\u6027\u5141\u8bb8\u591a\u6761\u89c4\u5219\u5e94\u7528\u4e8e\u540c\u4e00\u5143\u7d20\uff0c\u6839\u636e\u4f18\u5148\u7ea7\u548c\u6743\u91cd\u51b3\u5b9a\u6700\u7ec8\u6837\u5f0f\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">3. <strong>\u903b\u8f91\u9009\u62e9\u5668<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">\u4f7f\u7528\u4f2a\u7c7b\u548c\u903b\u8f91\u64cd\u4f5c\u5b9e\u73b0\u590d\u6742\u5339\u914d\uff1a<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:is()<\/code>\uff1a\u5339\u914d\u591a\u4e2a\u9009\u62e9\u5668\u4e4b\u4e00\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  :is(h1, h2, h3) {\n    margin: 0;\n  }<\/code><\/pre>\n\n\n\n<ul class=\"wp-block-list\">\n<li><code>:not()<\/code>\uff1a\u6392\u9664\u7279\u5b9a\u9009\u62e9\u5668\u3002<\/li>\n<\/ul>\n\n\n\n<pre class=\"wp-block-code\"><code>  div:not(.active) {\n    opacity: 0.5;\n  }<\/code><\/pre>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p class=\"wp-block-paragraph\">\u901a\u8fc7\u7cfb\u7edf\u638c\u63e1\u4e0a\u8ff0\u9009\u62e9\u5668\uff0c\u4f60\u53ef\u4ee5\u5728\u9879\u76ee\u4e2d\u9ad8\u6548\u5730\u7b5b\u9009\u3001\u5339\u914d\u5143\u7d20\u5e76\u63a7\u5236\u6837\u5f0f\u3002<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u4ee5\u4e0a\u4e3a\u5982\u4f55\u6709\u6548\u638c\u63e1css\u9009\u62e9\u5668\u7684\u8be6\u7ec6\u4ecb\u7ecd\uff0c\u66f4\u591a\u4fe1\u606f\u8bf7\u5173\u6ce8\u5176\u4ed6\u76f8\u5173\u6587\u7ae0\uff01<\/p>\n","protected":false},"excerpt":{"rendered":"<p>CSS \u9009\u62e9\u5668\u662f\u524d\u7aef\u5f00\u53d1\u4e2d\u7684\u57fa\u7840\u548c\u6838\u5fc3\uff0c\u7528\u4e8e\u9009\u62e9 HTML \u5143\u7d20\u5e76\u5e94\u7528\u6837\u5f0f\u3002\u4ee5\u4e0b\u6307\u5357\u4ece\u57fa\u7840\u5230\u9ad8\u7ea7\u9010\u6b65\u8bb2\u89e3 CS [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[55],"tags":[],"class_list":["post-177","post","type-post","status-publish","format-standard","hentry","category-css"],"_links":{"self":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/177","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/comments?post=177"}],"version-history":[{"count":1,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/177\/revisions"}],"predecessor-version":[{"id":178,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/posts\/177\/revisions\/178"}],"wp:attachment":[{"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/media?parent=177"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/categories?post=177"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.laixuexila.com\/index.php\/wp-json\/wp\/v2\/tags?post=177"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}