{"id":11788,"date":"2025-07-25T17:52:50","date_gmt":"2025-07-25T09:52:50","guid":{"rendered":"https:\/\/www.zhangxinxu.com\/wordpress\/?p=11788"},"modified":"2025-12-02T20:59:39","modified_gmt":"2025-12-02T12:59:39","slug":"css-if-function","status":"publish","type":"post","link":"https:\/\/www.zhangxinxu.com\/wordpress\/2025\/07\/css-if-function\/","title":{"rendered":"CSS\u5012\u53cd\u5929\u7f61\u5c45\u7136\u652f\u6301if()\u51fd\u6570\u4e86"},"content":{"rendered":"<p>by <a href=\"https:\/\/www.zhangxinxu.com\/\">zhangxinxu<\/a> from <a href=\"https:\/\/www.zhangxinxu.com\/wordpress\/?p=11788\">https:\/\/www.zhangxinxu.com\/wordpress\/?p=11788<\/a><br \/>\n\u672c\u6587\u53ef\u5168\u6587\u8f6c\u8f7d\uff0c\u4f46\u9700\u8981\u4fdd\u7559\u539f\u4f5c\u8005\u3001\u51fa\u5904\u4ee5\u53ca\u6587\u4e2d\u94fe\u63a5\uff0cAI\u6293\u53d6\u4fdd\u7559\u539f\u6587\u5730\u5740\uff0c\u4efb\u4f55\u7f51\u7ad9\u5747\u53ef\u6458\u8981\u805a\u5408\uff0c\u5546\u7528\u8bf7\u8054\u7cfb\u6388\u6743\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202507\/2025-7-25_174045.jpeg\" width=\"391\" height=\"245\" alt=\"CSS if()\u51fd\u6570\u5360\u4f4d\u56fe\u5c01\u9762\u56fe\" class=\"alignright clip thumb size-medium\" \/><\/p>\n<h3>\u4e00\u3001CSS\u771f\u903b\u8f91\u51fd\u6570<\/h3>\n<p>CSS\u4e4b\u524d\u4e5f\u652f\u6301\u7c7b\u903b\u8f91\u51fd\u6570\uff0c\u4f8b\u5982\u6570\u5b66\u51fd\u6570\u4e2d\u7684<code>min()<\/code>\u3001<code>max()<\/code>\uff0c\u672c\u8d28\u4e0a\u4e5f\u662f\u6709\u903b\u8f91\u7684\uff0c\u4f8b\u5982\uff1amax(300px, 100vw)\uff0c\u8868\u793a:<\/p>\n<ul>\n<li>\u5982\u679c100vw\u7684\u8ba1\u7b97\u5bbd\u5ea6\u5927\u4e8e300px\uff0c\u5219\u6700\u7ec8\u5c3a\u5bf8300px<\/li>\n<li>\u5426\u5219\u662f100vw\u7684\u5bbd\u5ea6\u3002<\/li>\n<\/ul>\n<p>\u73b0\u5728\uff0cCSS\u652f\u6301 <code>if()<\/code> \u51fd\u6570\u4e86\uff0c\u8fd9\u4e2a\u662f\u771f\u6b63\u610f\u4e49\u4e0a\u7684\u903b\u8f91\u51fd\u6570\u4e86\u3002<\/p>\n<p>\u76ee\u524d\uff0c<code>if()<\/code> \u652f\u6301\u4e09\u79cd\u4e0d\u540c\u7c7b\u578b\u7684\u67e5\u8be2\uff1a<\/p>\n<ul>\n<li>style()\uff1a\u6837\u5f0f\u67e5\u8be2<\/li>\n<li>media()\uff1a\u5a92\u4f53\u67e5\u8be2<\/li>\n<li>supports()\uff1a\u652f\u6301\u67e5\u8be2<\/li>\n<\/ul>\n<p>\u5176\u4e2d\uff0c<code>media()<\/code>\u548c<code>supports()<\/code>\u67e5\u8be2\u5e73\u65f6\u6211\u4eec\u4f7f\u7528\u7684\u673a\u4f1a\u4e0d\u591a\uff0c\u539f\u56e0\u5f88\u7b80\u5355\uff0c\u56e0\u4e3a\u6709\u517c\u5bb9\u6027\u66f4\u597d\u7684\u4f20\u7edf\u5b9e\u73b0\u65b9\u6cd5\u3002\u4f8b\u5982\uff0c\u4e0b\u9762\u7684CSS\u4ee3\u7801\u7247\u6bb5\u4f5c\u7528\u662f\u4e00\u6837\u7684\uff1a<\/p>\n<pre>button {\r\n  aspect-ratio: 1;\r\n  width: if(media(any-pointer: fine): 30px; else: 44px);\r\n}<\/pre>\n<pre>button {\r\n  aspect-ratio: 1;\r\n  width: 44px;\r\n}\r\n\r\n@media (any-pointer: fine) {\r\n  button {\r\n    width: 30px;\r\n  }\r\n}<\/pre>\n<p>\u4f46\u662f\u540e\u8005\u7684\u517c\u5bb9\u6027\u66f4\u597d\uff0c\u53ef\u8bfb\u6027\u4e5f\u66f4\u597d\uff0c\u5728\u76ee\u524d\u8fd9\u4e2a\u9636\u6bb5\uff0c\u80af\u5b9a\u662f\u4f18\u5148\u4f7f\u7528\u540e\u9762\u7684\u65b9\u6cd5\u3002<\/p>\n<p><code>supports()<\/code>\u67e5\u8be2\u4e5f\u662f\u7c7b\u4f3c\u7684\uff1a<\/p>\n<pre>select {\r\n  opacity: if (\r\n    supports(appearance: base-select): 1; else: 0;\r\n  );\r\n}<\/pre>\n<p>\u7b49\u540c\u4e8e\uff1a<\/p>\n<pre>@supports not (appearance: base-select) {\r\n  select {\r\n    opacity: 0;\r\n  }\r\n}<\/pre>\n<p>\u6ce8\u610f\uff0c\u5173\u952e\u5b57 <code>else<\/code> \u662f\u5728 <code>if()<\/code> \u51fd\u6570\u91cc\u9762\u7684\u3002<\/p>\n<p><code>style()<\/code> \u6837\u5f0f\u67e5\u8be2\u4e5f\u6709\u5bf9\u5e94\u7684\u67e5\u8be2\uff0c\u4e0d\u8fc7\u8fd9\u4e2a\u67e5\u8be2\u662f\u4e5f\u662f\u65b0\u7279\u6027\u3002\u4f8b\u5982\uff1a<\/p>\n<pre>canvas {\r\n  background-image: if(\r\n    style(--scheme: ice): linear-gradient(aliceblue, white, skyblue);\r\n    style(--scheme: fire): linear-gradient(lightyellow, white, yellow);\r\n    else: none;\r\n  );\r\n}<\/pre>\n<p>\u7c7b\u4f3c\u4e8e\uff1a<\/p>\n<pre>@container style(--scheme: ice) {\r\n  canvas {\r\n    linear-gradient(skyblue, white, #caf0f8);\r\n  }\r\n}\r\n@container style(--scheme: fire) {\r\n  canvas {\r\n    linear-gradient(lightyellow, white, yellow);\r\n  }\r\n}<\/pre>\n<p>\u6ce8\u610f\uff0c\u4e0a\u9762\u7684\u63aa\u8f9e\u662f\u201c\u7c7b\u4f3c\u4e8e\u201d\uff0c\u5e76\u672a\u5b8c\u5168\u76f8\u7b49\uff0c\u5982\u679c<code>--scheme: ice<\/code>\u662f\u5199\u5728<code>&lt;canvas&gt;<\/code>\u5143\u7d20\u4e0a\uff0c\u4e24\u8005\u5e76\u4e0d\u76f8\u540c\uff0c\u9700\u8981\u5728\u5bb9\u5668\u5143\u7d20\u4e0a\u3002<\/p>\n<p>\u5047\u8bbe\u6709HTML\u5982\u4e0b\uff1a<\/p>\n<pre>&lt;canvas style=\"--scheme: ice\"&gt;&lt;\/canvas&gt;\r\n&lt;canvas style=\"--scheme: fire\"&gt;&lt;\/canvas&gt;<\/pre>\n<p>\u5219\u5b9e\u65f6\u6e32\u67d3\u6548\u679c\u5982\u4e0b\uff1a<\/p>\n<p><canvas style=\"--scheme: ice\"><\/canvas> <canvas style=\"--scheme: fire\"><\/canvas><\/p>\n<style>canvas {background-image: if(style(--scheme: ice): linear-gradient(aliceblue, white, skyblue);style(--scheme: fire): linear-gradient(lightyellow, white, yellow);else: none;);}<\/style>\n<p>\u7531\u4e8e<code>if()<\/code>\u51fd\u6570\u4e2d\u7684<code>style()<\/code>\u67e5\u8be2\u66f4\u52a0\u5177\u6709\u4e0d\u53ef\u66ff\u4ee3\u6027\uff0c\u56e0\u6b64\uff0c\u8fd9\u4e2a\u51fd\u6570\u63a5\u4e0b\u6765\u6211\u4f1a\u91cd\u70b9\u8bb2\u8ff0\u3002<\/p>\n<h3>\u4e8c\u3001style()\u4e0eCSS\u53d8\u91cf\u5339\u914d<\/h3>\n<p><code>style()<\/code> \u6837\u5f0f\u67e5\u8be2\u53ea\u80fd\u67e5\u8be2CSS\u53d8\u91cf\uff0c\u666e\u901aCSS\u5c5e\u6027\u662f\u4e0d\u652f\u6301\u7684\u3002<\/p>\n<p>\u6211\u4eec\u6765\u770b\u4e00\u4e2a\u6848\u4f8b\uff0c\u4e86\u89e3\u4e0b\u662f\u5982\u4f55\u4f7f\u7528\u7684\uff0c\u60f3\u4e86\u4e0b\uff0c\u6628\u5929\u7528\u5230\u7684\u4e00\u4e2aCSS Sprites\u5b9a\u4f4d\u975e\u5e38\u4f7f\u7528\u6b64\u6548\u679c\u3002<\/p>\n<p>\u4e0b\u56fe\u6240\u793a\u7684\u5c31\u662f\u7d20\u6750\uff1a<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202507\/sprite-badge-min.png\" width=\"232\" height=\"252\" alt=\"Sprites\u539f\u56fe\" class=\"alignnone size-medium\" \/><\/p>\n<p>\u5728\u8fc7\u53bb\uff0c\u6211\u4eec\u53ef\u80fd\u9700\u8981\u5bf94\u4e2a\u5143\u7d20\u4f7f\u7528\u4e0d\u540c\u7684\u9009\u62e9\u5668\u8fdb\u884c\u5904\u7406\uff0c\u73b0\u5728\uff0c\u53ef\u4ee5\u4e00\u628ahold\u4f4f\u4e86\u3002<\/p>\n<p>\u76f8\u5173\u4ee3\u7801\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n<pre>&lt;label class=\"label\" style=\"--type: 1\"&gt;\u9605\u7bc7\u4e13\u5bb6&lt;\/label&gt;\r\n&lt;label class=\"label\" style=\"--type: 2\"&gt;\u4e07\u5b57\u5468\u62a5\u5927\u5e08&lt;\/label&gt;\r\n&lt;label class=\"label\" style=\"--type: 3\"&gt;\u4e92\u52a8\u6025\u5148\u950b&lt;\/label&gt;\r\n&lt;label class=\"label\" style=\"--type: 4\"&gt;\u4f73\u4f5c\u5206\u4eab\u8fbe\u4eba&lt;\/label&gt;<\/pre>\n<p>\u6b64\u65f6\uff0c\u53ea\u9700\u8981\u4e00\u6bb5CSS\u89c4\u5219\u5c31\u53ef\u4ee5\u5b9e\u73b0\u6240\u6709\u56fe\u6807\u7684\u6837\u5f0f\u6548\u679c\u4e86\uff1a<\/p>\n<pre>.label {\r\n  display: inline-block;\r\n  font-size: 0;\r\n  width: if(\r\n    style(--type: 1): 80px;\r\n    style(--type: 3): 96px;\r\n    else: 112px;\r\n  );\r\n  height: 26px;\r\n  background: url(sprite.png) no-repeat 0 0 \/ 116px auto;\r\n  background-position-y: if(\r\n    style(--type: 2): -34px;\r\n    style(--type: 3): -68px;\r\n    style(--type: 4): -102px;\r\n    else: 0px;\r\n  );\r\n}<\/pre>\n<p>\u6e32\u67d3\u6548\u679c\u5982\u4e0b\u56fe\u6240\u793a\uff1a<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202507\/2025-7-25_170928.png\" width=\"225\" height=\"93\" alt=\"\u5b9e\u9645\u6e32\u67d3\u7ed3\u679c\u622a\u56fe\" class=\"alignnone size-medium\" \/><\/p>\n<p>\u662f\u4e0d\u662f\u6bd4\u8fc7\u53bb\u7684\u4ee3\u7801\u66f4\u52a0\u7b80\u7ea6\u4e86\u3002<\/p>\n<h3>\u4e09\u3001\u6700\u5927\u7684\u963b\u788d\u517c\u5bb9\u6027<\/h3>\n<p><code>if()<\/code>\u51fd\u6570\u867d\u7136\u5f88\u5c4c\u5f88\u5e05\u6c14\uff0c\u4f46\u662f\u517c\u5bb9\u6027\u8fd8\u4e0d\u884c\uff0c\u76ee\u524d\u4ec5Chrome 137+\u6d4f\u89c8\u5668\u652f\u6301\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202507\/2025-7-25_173538.png\" width=\"646\" height=\"322\" alt=\"if()\u51fd\u6570\u7684\u517c\u5bb9\u6027\" class=\"alignnone size-medium\" \/><\/p>\n<p>\u53e6\u5916\uff0c<code>if()<\/code>\u51fd\u6570\u5f0f\u652f\u6301\u5d4c\u5957\u7684\uff1a<\/p>\n<pre>color: if(\r\n  style(--scheme: ice):\r\n    if(\r\n      media(prefers-color-scheme: dark): #caf0f8;\r\n      else: #03045e;\r\n    );\r\n  style(--scheme: fire):\r\n    if(\r\n      media(prefers-color-scheme: dark): #ffc971;\r\n      else: #621708;\r\n    );\r\n  else: black\r\n);<\/pre>\n<p>\u5176\u4ed6\u5c31\u6ca1\u4ec0\u4e48\u4e86\uff0c\u9759\u5f85\u6d4f\u89c8\u5668\u5168\u9762\u652f\u6301\u5427\u3002<\/p>\n<p>\u611f\u8c22\u9605\u8bfb\uff0c\u5b8b\u7389\u957f\u8001\u5e0c\u671b\u4f60\u8f6c\u53d1\u8fd9\u7bc7\u6587\u7ae0\uff01<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202507\/2025-7-28_140316.jpeg\" width=\"170\" height=\"130\" alt=\"\u5b8b\u7389\u559d\u8336\" class=\"alignnone size-medium\" \/><\/p>\n<p>\ud83d\ude09\ud83d\ude0a\ud83d\ude07<br \/>\n\ud83e\udd70\ud83d\ude0d\ud83d\ude18<\/p>\n<p>\u672c\u6587\u4e3a\u539f\u521b\u6587\u7ae0\uff0c\u4f1a\u7ecf\u5e38\u66f4\u65b0\u77e5\u8bc6\u70b9\u4ee5\u53ca\u4fee\u6b63\u4e00\u4e9b\u9519\u8bef\uff0c\u56e0\u6b64\u8f6c\u8f7d\u8bf7\u4fdd\u7559\u539f\u51fa\u5904\uff0c\u65b9\u4fbf\u6eaf\u6e90\uff0c\u907f\u514d\u9648\u65e7\u9519\u8bef\u77e5\u8bc6\u7684\u8bef\u5bfc\uff0c\u540c\u65f6\u6709\u66f4\u597d\u7684\u9605\u8bfb\u4f53\u9a8c\u3002<br \/>\n\u672c\u6587\u5730\u5740\uff1a<a href=\"https:\/\/www.zhangxinxu.com\/wordpress\/?p=11788\">https:\/\/www.zhangxinxu.com\/wordpress\/?p=11788<\/a><\/p>\n<p>\uff08\u672c\u7bc7\u5b8c\uff09<\/p>\n","protected":false},"excerpt":{"rendered":"<p><img decoding=\"async\" src=\"https:\/\/image.zhangxinxu.com\/image\/blog\/202507\/2025-7-25_174045.jpeg\" width=\"160\" height=\"100\" alt=\"CSS if()\u51fd\u6570\u5360\u4f4d\u56fe\u5c01\u9762\u56fe\" class=\"alignright size-medium\" loading=\"lazy\" \/><\/p>\n<p>\u60f3\u4e0d\u5230\u5427\uff0cCSS\u5c45\u7136\u4e5f\u652f\u6301if() else \u903b\u8f91\u51fd\u6570\u4e86\uff0c\u8fd9\u662f\u94c1\u4e86\u5fc3\u8981\u5e72\u6389JavaScript\u7684\u8282\u594f\u554a\u3002<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[1015,1012,1561,1591,1506,1595,575],"_links":{"self":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/11788"}],"collection":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/comments?post=11788"}],"version-history":[{"count":8,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/11788\/revisions"}],"predecessor-version":[{"id":11992,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/posts\/11788\/revisions\/11992"}],"wp:attachment":[{"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/media?parent=11788"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/categories?post=11788"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zhangxinxu.com\/wordpress\/wp-json\/wp\/v2\/tags?post=11788"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}