.header-image-only #blog-title #blog-title-inner { position: relative; background-size: cover; height: auto; } .header-image-only #blog-title #blog-title-inner:before { display: block; content: ""; width: 100%; padding-top: （画像の縦÷横）%; } .header-image-only #blog-title #blog-title-content { position: absolute; top: 0; left: 0; right: 0; bottom: 0; }