{"id":9496,"date":"2026-02-03T11:46:35","date_gmt":"2026-02-03T02:46:35","guid":{"rendered":"https:\/\/fastcoding.jp\/blog\/?p=9496"},"modified":"2026-02-03T11:46:55","modified_gmt":"2026-02-03T02:46:55","slug":"cls-layout-shift-html-css","status":"publish","type":"post","link":"https:\/\/fastcoding.jp\/blog\/all\/seo\/cls-layout-shift-html-css\/","title":{"rendered":"CLS\u3067\u4fe1\u983c\u3092\u843d\u3068\u3055\u306a\u3044 \u2500 &#8220;\u30ac\u30bf\u3064\u304b\u306a\u3044&#8221;\u753b\u50cf\u30fb\u5e83\u544a\u67a0\u306eHTML\/CSS\u8a2d\u8a08"},"content":{"rendered":"<div class=\"the_content\">\n<p>\u3053\u3093\u306b\u3061\u306f\uff01\u682a\u5f0f\u4f1a\u793e\u30d5\u30a1\u30b9\u30c8\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u306eWeb\u30c7\u30a3\u30ec\u30af\u30bf\u30fc\u306e\u50cd\u304f\u304a\u304b\u3093\u3067\u3059\u3002<br>\u6bce\u5e74\u8a00\u3063\u3066\u3044\u308b\u6c17\u304c\u3057\u307e\u3059\u304c\u3001\u4eca\u5e74\u3001\u3061\u3087\u3063\u3068\u5bd2\u3059\u304e\u306a\u3044\u3067\u3057\u3087\u3046\u304b\u3002\u5b50\u4f9b\u306e\u9803\u306f\u30011\u6708\u3082\u4e0b\u65ec\u306b\u306a\u308c\u3070\u5bd2\u3055\u304c\u548c\u3089\u3044\u3060\u6c17\u304c\u3057\u305f\u3093\u3067\u3059\u304c\u3002\u30a8\u30a2\u30b3\u30f3\u306f\u3064\u3051\u3066\u3044\u308b\u3082\u306e\u306e\u3001\u30ad\u30fc\u30dc\u30fc\u30c9\u3092\u53e9\u304f\u6307\u304c\u3068\u3066\u3082\u51b7\u305f\u3044\u306e\u3067\u3001\u624b\u888b\u3092\u3057\u306a\u304c\u3089\u30d6\u30ed\u30b0\u3092\u66f8\u3044\u3066\u3044\u307e\u3059\u3002<br>\uff0a\u305d\u3057\u3066\u4eca\u5e74\u521d\u6295\u7a3f\u3067\u3059\uff01\u4eca\u5e74\u3082\u3088\u308d\u3057\u304f\u304a\u9858\u3044\u3057\u307e\u3059\uff01<\/p>\n\n\n\n<p>\u4eca\u65e5\u306e\u8a71\u984c\u306f\u30da\u30fc\u30b8\u306e\u30ac\u30bf\u30c4\u30ad\u3001\u3067\u3059\u3002Web\u30b5\u30a4\u30c8\u3092\u95b2\u89a7\u3057\u3066\u3044\u308b\u3068\u3001\u30dc\u30bf\u30f3\u3092\u62bc\u305d\u3046\u3068\u3057\u305f\u77ac\u9593\u306b\u5e83\u544a\u304c\u51fa\u3066\u304d\u3066\u8aa4\u30bf\u30c3\u30d7\u3057\u3066\u3057\u307e\u3046\u3001\u8aad\u3093\u3067\u3044\u305f\u5834\u6240\u304c\u6025\u306b\u305a\u308c\u308b\u3001\u3068\u3044\u3063\u305f\u7d4c\u9a13\u306f\u3042\u308a\u307e\u305b\u3093\u304b\uff1f\u3042\u306e\u300c\u30a4\u30e9\u30c3\u300d\u3068\u3059\u308b\u73fe\u8c61\u3001\u5b9f\u306f<strong>CLS\uff08Cumulative Layout Shift\uff09<\/strong>\u3068\u3044\u3046\u540d\u524d\u304c\u3064\u3044\u3066\u3044\u3066\u3001Google\u3082\u554f\u984c\u8996\u3057\u3066\u3044\u308b\u6307\u6a19\u306a\u3093\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u4eca\u56de\u306f\u3001\u3053\u306eCLS\u3092\u6539\u5584\u3059\u308b\u305f\u3081\u306eHTML\/CSS\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u306b\u3064\u3044\u3066\u3054\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">CLS\u3068\u306f\u4f55\u304b<\/h2>\n\n\n\n<p>CLS\u306f<strong>\u300c\u8aad\u307f\u8fbc\u307f\u4e2d\u306b\u30da\u30fc\u30b8\u304c\u3069\u308c\u3060\u3051\u30ac\u30bf\u30ac\u30bf\u52d5\u304f\u304b\u300d<\/strong>\u3092\u6570\u5024\u5316\u3057\u305f\u3082\u306e\u3067\u3059\u3002Google\u306f0.1\u4ee5\u4e0b\u3092\u300c\u826f\u597d\u300d\u3068\u3057\u3066\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<p>CLS\u304c\u9ad8\u3044\u3068\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u554f\u984c\u304c\u767a\u751f\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u8aa4\u30bf\u30c3\u30d7\u30fb\u8aa4\u30af\u30ea\u30c3\u30af<\/strong>\uff1a\u62bc\u3057\u305f\u3044\u30dc\u30bf\u30f3\u304c\u79fb\u52d5\u3057\u3066\u5225\u306e\u8981\u7d20\u3092\u30bf\u30c3\u30d7\u3057\u3066\u3057\u307e\u3046<\/li>\n\n\n\n<li><strong>\u8aad\u3093\u3067\u3044\u305f\u4f4d\u7f6e\u3092\u898b\u5931\u3046<\/strong>\uff1a\u753b\u50cf\u306e\u8aad\u307f\u8fbc\u307f\u3067\u6587\u7ae0\u304c\u62bc\u3057\u4e0b\u3052\u3089\u308c\u308b<\/li>\n\n\n\n<li><strong>\u30b5\u30a4\u30c8\u3078\u306e\u4e0d\u4fe1\u611f<\/strong>\uff1a\u30ac\u30bf\u3064\u304f\u30b5\u30a4\u30c8\u306f\u4e0d\u5b89\u5b9a\u306a\u5370\u8c61\u3092\u4e0e\u3048\u308b<\/li>\n\n\n\n<li><strong>SEO\u3078\u306e\u60aa\u5f71\u97ff<\/strong>\uff1aCore Web Vitals\u306e\u4e00\u3064\u3068\u3057\u3066\u8a55\u4fa1\u306b\u5f71\u97ff\u3059\u308b<\/li>\n<\/ul>\n\n\n\n<p>\u7279\u306bEC\u30b5\u30a4\u30c8\u3084\u7533\u3057\u8fbc\u307f\u30d5\u30a9\u30fc\u30e0\u304c\u3042\u308b\u30b5\u30a4\u30c8\u3067\u306f\u3001CLS\u306e\u60aa\u5316\u304c\u30b3\u30f3\u30d0\u30fc\u30b8\u30e7\u30f3\u7387\u306e\u4f4e\u4e0b\u306b\u76f4\u7d50\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">CLS\u304c\u767a\u751f\u3059\u308b\u4e3b\u306a\u539f\u56e0<\/h2>\n\n\n\n<p>CLS\u304c\u767a\u751f\u3059\u308b\u539f\u56e0\u306f\u3001\u4e3b\u306b\u4ee5\u4e0b\u306e4\u3064\u3067\u3059\u3002<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>\u30b5\u30a4\u30ba\u6307\u5b9a\u306e\u306a\u3044\u753b\u50cf<\/strong>\uff1a\u8aad\u307f\u8fbc\u307f\u5b8c\u4e86\u5f8c\u306b\u30b9\u30da\u30fc\u30b9\u3092\u78ba\u4fdd\u3059\u308b<\/li>\n\n\n\n<li><strong>\u9045\u5ef6\u8aad\u307f\u8fbc\u307f\u3055\u308c\u308b\u5e83\u544a<\/strong>\uff1a\u5f8c\u304b\u3089\u8868\u793a\u3055\u308c\u3066\u4ed6\u306e\u8981\u7d20\u3092\u62bc\u3057\u4e0b\u3052\u308b<\/li>\n\n\n\n<li><strong>Web\u30d5\u30a9\u30f3\u30c8<\/strong>\uff1a\u30d5\u30a9\u30f3\u30c8\u5207\u308a\u66ff\u3048\u6642\u306b\u6587\u5b57\u30b5\u30a4\u30ba\u304c\u5909\u308f\u308b<\/li>\n\n\n\n<li><strong>JavaScript\u3067\u52d5\u7684\u306b\u8ffd\u52a0\u3055\u308c\u308b\u8981\u7d20<\/strong>\uff1a\u304a\u77e5\u3089\u305b\u30d0\u30fc\u3084Cookie\u540c\u610f\u30d0\u30ca\u30fc\u306a\u3069<\/li>\n<\/ol>\n\n\n\n<p>\u4eca\u56de\u306f\u7279\u306b<strong>\u753b\u50cf\u3068\u5e83\u544a<\/strong>\u306e\u5bfe\u7b56\u3092\u4e2d\u5fc3\u306b\u3054\u7d39\u4ecb\u3057\u307e\u3059\u3002\u3053\u306e2\u3064\u3092\u62bc\u3055\u3048\u3066\u304a\u3051\u3070\u3001\u591a\u304f\u306e\u30b1\u30fc\u30b9\u3067\u6539\u5584\u304c\u898b\u8fbc\u3081\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5bfe\u7b56\u2460\uff1aaspect-ratio\u3067\u4e8b\u524d\u306b\u30b9\u30da\u30fc\u30b9\u3092\u78ba\u4fdd\u3059\u308b<\/h2>\n\n\n\n<p>\u6700\u3082\u52b9\u679c\u7684\u306a\u306e\u304c\u3001CSS\u306e<code>aspect-ratio<\/code>\u30d7\u30ed\u30d1\u30c6\u30a3\u3067\u3059\u3002\u3053\u308c\u306f<strong>\u300c\u753b\u50cf\u304c\u8aad\u307f\u8fbc\u307e\u308c\u308b\u524d\u304b\u3089\u3001\u305d\u306e\u5206\u306e\u30b9\u30da\u30fc\u30b9\u3092\u78ba\u4fdd\u3057\u3066\u304a\u304f\u300d<\/strong>\u3068\u3044\u3046\u5f79\u5272\u3092\u679c\u305f\u3057\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u57fa\u672c\u306e\u66f8\u304d\u65b9<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;!-- HTML\uff1awidth\u3068height\u5c5e\u6027\u3092\u8a18\u8ff0\u3059\u308b --&gt;\n&lt;img \n  src=\"hero-image.jpg\" \n  alt=\"\u30e1\u30a4\u30f3\u753b\u50cf\"\n  width=\"1200\"\n  height=\"630\"\n  class=\"hero-image\"\n&gt;<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* CSS *\/\n.hero-image {\n  width: 100%;\n  height: auto;\n  aspect-ratio: 1200 \/ 630;  \/* \u5e45 \u00f7 \u9ad8\u3055 \u306e\u6bd4\u7387 *\/\n  object-fit: cover;\n}<\/code><\/pre>\n\n\n\n<p><strong>\u91cd\u8981\u306a\u30dd\u30a4\u30f3\u30c8<\/strong>\u3068\u3057\u3066\u3001HTML\u306e<code>width<\/code>\u3068<code>height<\/code>\u5c5e\u6027\u3082\u5fc5\u305a\u8a18\u8ff0\u3057\u3066\u304f\u3060\u3055\u3044\u3002\u6700\u8fd1\u306e\u30d6\u30e9\u30a6\u30b6\u306f\u3053\u306e\u5c5e\u6027\u3092\u898b\u3066\u81ea\u52d5\u3067\u30a2\u30b9\u30da\u30af\u30c8\u6bd4\u3092\u8a08\u7b97\u3059\u308b\u305f\u3081\u3001\u3053\u308c\u3060\u3051\u3067\u3082\u304b\u306a\u308a\u6539\u5584\u3057\u307e\u3059\u3002CSS\u306e<code>aspect-ratio<\/code>\u3068\u4f75\u7528\u3059\u308b\u3053\u3068\u3067\u3001\u3088\u308a\u78ba\u5b9f\u306b\u5bfe\u7b56\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u3088\u304f\u4f7f\u3046\u30a2\u30b9\u30da\u30af\u30c8\u6bd4<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* YouTube\u52d5\u753b\u306a\u3069 \u2192 16:9 *\/\n.video-thumbnail {\n  aspect-ratio: 16 \/ 9;\n}\n\n\/* \u6b63\u65b9\u5f62\uff08SNS\u6295\u7a3f\u98a8\uff09 \u2192 1:1 *\/\n.square-image {\n  aspect-ratio: 1 \/ 1;\n}\n\n\/* OGP\u753b\u50cf\uff08SNS\u30b7\u30a7\u30a2\u7528\uff09 \u2192 1.91:1 *\/\n.ogp-image {\n  aspect-ratio: 1.91 \/ 1;\n}<\/code><\/pre>\n\n\n\n<p>\u30b5\u30a4\u30c8\u3067\u4f7f\u7528\u3059\u308b\u753b\u50cf\u6bd4\u7387\u304c\u6c7a\u307e\u3063\u3066\u3044\u308b\u5834\u5408\u306f\u3001\u3042\u3089\u304b\u3058\u3081\u30af\u30e9\u30b9\u3068\u3057\u3066\u5b9a\u7fa9\u3057\u3066\u304a\u304f\u3068\u904b\u7528\u304c\u697d\u306b\u306a\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5bfe\u7b56\u2461\uff1a\u8aad\u307f\u8fbc\u307f\u4e2d\u306e\u30d7\u30ec\u30fc\u30b9\u30db\u30eb\u30c0\u30fc\u3092\u8868\u793a\u3059\u308b<\/h2>\n\n\n\n<p>\u30b9\u30da\u30fc\u30b9\u3092\u78ba\u4fdd\u3067\u304d\u305f\u3089\u3001\u6b21\u306f<strong>\u300c\u8aad\u307f\u8fbc\u307f\u4e2d\u3067\u3042\u308b\u3053\u3068\u300d\u3092\u8996\u899a\u7684\u306b\u4f1d\u3048\u308b<\/strong>\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002\u771f\u3063\u767d\u306a\u307e\u307e\u3060\u3068\u3001\u8868\u793a\u304c\u58ca\u308c\u3066\u3044\u308b\u3088\u3046\u306b\u898b\u3048\u3066\u3057\u307e\u3044\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u30b7\u30f3\u30d7\u30eb\u306a\u80cc\u666f\u8272\u3092\u8a2d\u5b9a\u3059\u308b\u65b9\u6cd5<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>.image-container {\n  aspect-ratio: 16 \/ 9;\n  background-color: #f0f0f0;  \/* \u8584\u3044\u30b0\u30ec\u30fc *\/\n}\n\n.image-container img {\n  width: 100%;\n  height: 100%;\n  object-fit: cover;\n}<\/code><\/pre>\n\n\n\n<p>\u3053\u308c\u3060\u3051\u3067\u3082\u300c\u3053\u3053\u306b\u753b\u50cf\u304c\u5165\u308b\u300d\u3068\u3044\u3046\u3053\u3068\u304c\u8996\u899a\u7684\u306b\u4f1d\u308f\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u30b9\u30b1\u30eb\u30c8\u30f3\u30ed\u30fc\u30c7\u30a3\u30f3\u30b0\u3092\u5b9f\u88c5\u3059\u308b\u65b9\u6cd5<\/h3>\n\n\n\n<p>EC\u30b5\u30a4\u30c8\u306a\u3069\u3067\u3088\u304f\u898b\u304b\u3051\u308b\u3001\u30b0\u30ec\u30fc\u304c\u30ad\u30e9\u30ad\u30e9\u3068\u5149\u308b\u30a2\u30cb\u30e1\u30fc\u30b7\u30e7\u30f3\u3082\u5b9f\u88c5\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>.skeleton-image {\n  aspect-ratio: 16 \/ 9;\n  background: linear-gradient(\n    90deg,\n    #f0f0f0 25%,\n    #e0e0e0 50%,\n    #f0f0f0 75%\n  );\n  background-size: 200% 100%;\n  animation: shimmer 1.5s infinite;\n}\n\n@keyframes shimmer {\n  0% { background-position: 200% 0; }\n  100% { background-position: -200% 0; }\n}<\/code><\/pre>\n\n\n\n<p>\u3053\u306e\u30a2\u30cb\u30e1\u30fc\u30b7\u30e7\u30f3\u3092\u5165\u308c\u308b\u3053\u3068\u3067\u3001\u300c\u8aad\u307f\u8fbc\u307f\u4e2d\u3067\u3042\u308b\u300d\u3053\u3068\u304c\u30e6\u30fc\u30b6\u30fc\u306b\u4f1d\u308f\u308a\u3001\u5f85\u3061\u6642\u9593\u306e\u30b9\u30c8\u30ec\u30b9\u3092\u8efd\u6e1b\u3067\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5bfe\u7b56\u2462\uff1a\u5e83\u544a\u67a0\u306bmin-height\u3092\u8a2d\u5b9a\u3059\u308b<\/h2>\n\n\n\n<p>\u5e83\u544a\u306f\u5f8c\u304b\u3089\u8aad\u307f\u8fbc\u307e\u308c\u308b\u3053\u3068\u304c\u591a\u304f\u3001\u30b5\u30a4\u30ba\u3082\u69d8\u3005\u306a\u305f\u3081\u3001CLS\u306e\u539f\u56e0\u306b\u306a\u308a\u3084\u3059\u3044\u8981\u7d20\u3067\u3059\u3002\u5bfe\u7b56\u3068\u3057\u3066\u306f\u3001<strong>\u300c\u6700\u4f4e\u9650\u306e\u9ad8\u3055\u3092\u78ba\u4fdd\u3057\u3066\u304a\u304f\u300d<\/strong>\u3053\u3068\u304c\u6709\u52b9\u3067\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">\u30b5\u30a4\u30ba\u304c\u6c7a\u307e\u3063\u3066\u3044\u308b\u5e83\u544a\u306e\u5834\u5408<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;!-- \u5e83\u544a\u3092\u5165\u308c\u308b\u30b3\u30f3\u30c6\u30ca --&gt;\n&lt;div class=\"ad-box ad-rectangle\"&gt;\n  &lt;!-- \u3053\u3053\u306b\u5e83\u544a\u30b3\u30fc\u30c9 --&gt;\n&lt;\/div&gt;<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* \u3088\u304f\u3042\u308b\u30b5\u30a4\u30ba\u5225\u306b\u5b9a\u7fa9 *\/\n\n\/* \u30ec\u30af\u30bf\u30f3\u30b0\u30eb\uff08300\u00d7250\uff09 *\/\n.ad-rectangle {\n  width: 300px;\n  min-height: 250px;\n  background-color: #fafafa;\n}\n\n\/* \u30b9\u30de\u30db\u30d0\u30ca\u30fc\uff08320\u00d750\uff09 *\/\n.ad-mobile {\n  width: 320px;\n  min-height: 50px;\n  background-color: #fafafa;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u30ec\u30b9\u30dd\u30f3\u30b7\u30d6\u5e83\u544a\u306e\u5834\u5408<\/h3>\n\n\n\n<p>AdSense\u306e\u3088\u3046\u306a\u30ec\u30b9\u30dd\u30f3\u30b7\u30d6\u5e83\u544a\u306f\u3001\u3069\u306e\u30b5\u30a4\u30ba\u304c\u914d\u4fe1\u3055\u308c\u308b\u304b\u5206\u304b\u308a\u307e\u305b\u3093\u3002\u305d\u306e\u5834\u5408\u306f\u3001<strong>\u60f3\u5b9a\u3055\u308c\u308b\u6700\u5927\u30b5\u30a4\u30ba\u3092\u57fa\u6e96\u306b\u9ad8\u3055\u3092\u78ba\u4fdd<\/strong>\u3057\u3066\u304a\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>.ad-responsive {\n  width: 100%;\n  min-height: 250px;  \/* \u60f3\u5b9a\u3055\u308c\u308b\u9ad8\u3055\u3092\u78ba\u4fdd *\/\n  background-color: #fafafa;\n}<\/code><\/pre>\n\n\n\n<p>\u5b8c\u74a7\u306b\u9632\u3050\u3053\u3068\u306f\u96e3\u3057\u3044\u3067\u3059\u304c\u3001\u5927\u304d\u306a\u30ec\u30a4\u30a2\u30a6\u30c8\u30b7\u30d5\u30c8\u306f\u9632\u3052\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5bfe\u7b56\u2463\uff1aYouTube\u30fbGoogle\u30de\u30c3\u30d7\u306e\u57cb\u3081\u8fbc\u307f<\/h2>\n\n\n\n<p>\u57cb\u3081\u8fbc\u307f\u7cfb\u306e\u30b3\u30f3\u30c6\u30f3\u30c4\u3082\u9045\u308c\u3066\u8aad\u307f\u8fbc\u307e\u308c\u308b\u305f\u3081\u3001\u540c\u69d8\u306b\u30b9\u30da\u30fc\u30b9\u3092\u78ba\u4fdd\u3057\u3066\u304a\u304d\u307e\u3059\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">YouTube\u306e\u5834\u5408<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>&lt;div class=\"video-box\"&gt;\n  &lt;iframe src=\"https:\/\/www.youtube.com\/embed\/xxxxx\"&gt;&lt;\/iframe&gt;\n&lt;\/div&gt;<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>.video-box {\n  aspect-ratio: 16 \/ 9;  \/* YouTube\u306f16:9 *\/\n  background-color: #000;  \/* \u9ed2\u80cc\u666f\u304c\u305d\u308c\u3063\u307d\u3044 *\/\n}\n\n.video-box iframe {\n  width: 100%;\n  height: 100%;\n}<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">Google\u30de\u30c3\u30d7\u306e\u5834\u5408<\/h3>\n\n\n\n<pre class=\"wp-block-code\"><code>.map-box {\n  aspect-ratio: 16 \/ 9;\n  background-color: #e5e3df;  \/* \u30de\u30c3\u30d7\u3063\u307d\u3044\u30d9\u30fc\u30b8\u30e5 *\/\n}\n\n.map-box iframe {\n  width: 100%;\n  height: 100%;\n}<\/code><\/pre>\n\n\n\n<p>\u8003\u3048\u65b9\u306f\u3059\u3079\u3066\u540c\u3058\u3067\u3001<strong>\u300c\u5f8c\u304b\u3089\u6765\u308b\u8981\u7d20\u306e\u5834\u6240\u3092\u5148\u306b\u78ba\u4fdd\u3059\u308b\u300d<\/strong>\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5bfe\u7b56\u2464\uff1aWeb\u30d5\u30a9\u30f3\u30c8\u306e\u3061\u3089\u3064\u304d\u5bfe\u7b56<\/h2>\n\n\n\n<p>Web\u30d5\u30a9\u30f3\u30c8\u304c\u8aad\u307f\u8fbc\u307e\u308c\u308b\u969b\u306b\u6587\u5b57\u304c\u30c1\u30e9\u30c3\u3068\u5909\u308f\u308b\u73fe\u8c61\u3082\u3001CLS\u306b\u5f71\u97ff\u3057\u307e\u3059\u3002\u5bfe\u7b56\u306f\u7c21\u5358\u3067\u3059\u3002<\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>\/* Google Fonts\u306e\u5834\u5408\u3001URL\u306bdisplay=swap\u3092\u3064\u3051\u308b *\/\n&lt;link href=\"https:\/\/fonts.googleapis.com\/css2?family=Noto+Sans+JP&amp;display=swap\" rel=\"stylesheet\"&gt;<\/code><\/pre>\n\n\n\n<p>\u3053\u308c\u306b\u3088\u308a\u3001\u30d5\u30a9\u30f3\u30c8\u304c\u8aad\u307f\u8fbc\u307e\u308c\u308b\u307e\u3067\u30b7\u30b9\u30c6\u30e0\u30d5\u30a9\u30f3\u30c8\u3067\u8868\u793a\u3055\u308c\u3001\u8aad\u307f\u8fbc\u307f\u5b8c\u4e86\u5f8c\u306b\u30b9\u30e0\u30fc\u30ba\u306b\u5207\u308a\u66ff\u308f\u308a\u307e\u3059\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u52b9\u679c\u306e\u78ba\u8a8d\u65b9\u6cd5<\/h2>\n\n\n\n<p>\u5bfe\u7b56\u3092\u5b9f\u88c5\u3057\u305f\u3089\u3001\u52b9\u679c\u3092\u78ba\u8a8d\u3057\u307e\u3057\u3087\u3046\u3002\u4ee5\u4e0b\u306e\u30c4\u30fc\u30eb\u304c\u4fbf\u5229\u3067\u3059\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>PageSpeed Insights<\/strong>\uff1ahttps:\/\/pagespeed.web.dev\/<\/li>\n\n\n\n<li><strong>Chrome DevTools<\/strong>\uff1aPerformance\u30bf\u30d6\u3067\u8a73\u7d30\u3092\u78ba\u8a8d\u3067\u304d\u308b<\/li>\n\n\n\n<li><strong>Web 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<code>display=swap<\/code>\u3092\u6307\u5b9a<\/li>\n<\/ul>\n\n\n\n<p>\u30ec\u30a4\u30a2\u30a6\u30c8\u304c\u30ac\u30bf\u3064\u304b\u306a\u3044\u30b5\u30a4\u30c8\u306f\u3001\u305d\u308c\u3060\u3051\u3067\u300c\u3057\u3063\u304b\u308a\u4f5c\u3089\u308c\u3066\u3044\u308b\u300d\u3068\u3044\u3046\u5370\u8c61\u3092\u4e0e\u3048\u307e\u3059\u3002\u30e6\u30fc\u30b6\u30fc\u306b\u5b89\u5fc3\u611f\u3092\u4e0e\u3048\u3089\u308c\u308b\u3060\u3051\u3067\u306a\u304f\u3001\u7279\u306bEC\u30b5\u30a4\u30c8\u3084\u7533\u3057\u8fbc\u307f\u7cfb\u306e\u30b5\u30a4\u30c8\u3067\u306f\u3001\u30b3\u30f3\u30d0\u30fc\u30b8\u30e7\u30f3\u306b\u3082\u5f71\u97ff\u3059\u308b\u91cd\u8981\u306a\u8981\u7d20\u3067\u3059\u3002<\/p>\n\n\n\n<p>\u682a\u5f0f\u4f1a\u793e\u30d5\u30a1\u30b9\u30c8\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u3067\u306f\u3001\u3053\u3046\u3057\u305f\u30d1\u30d5\u30a9\u30fc\u30de\u30f3\u30b9\u6539\u5584\u306e\u3054\u76f8\u8ac7\u3082\u627f\u3063\u3066\u3044\u307e\u3059\u3002CLS\u3092\u306f\u3058\u3081\u3068\u3059\u308bCore 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Vitals\u6539\u5584\u306b\u5f79\u7acb\u3064\u5b9f\u8df5\u7684\u306a\u30b3\u30fc\u30c7\u30a3\u30f3\u30b0\u624b\u6cd5\u3092\u7d39\u4ecb\u3057\u307e\u3059\u3002<\/p>\n","protected":false},"author":12,"featured_media":9536,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"enabled":false},"version":2}},"categories":[575,27],"tags":[298,33,32,28],"class_list":["post-9496","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-html-css","category-seo","tag-core-web-vitals","tag-css","tag-html","tag-seo"],"acf":[],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/fastcoding.jp\/blog\/wp-content\/uploads\/2026\/02\/79d9d7551ac73337e94f902642778415.png","jetpack_sharing_enabled":true,"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/posts\/9496","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/users\/12"}],"replies":[{"embeddable":true,"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/comments?post=9496"}],"version-history":[{"count":6,"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/posts\/9496\/revisions"}],"predecessor-version":[{"id":9533,"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/posts\/9496\/revisions\/9533"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/media\/9536"}],"wp:attachment":[{"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/media?parent=9496"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/categories?post=9496"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fastcoding.jp\/blog\/wp-json\/wp\/v2\/tags?post=9496"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}