Paste this code in the style.css file of you current active theme. (file path: /wp-content/themes/genesis-sample/style.css )

.entry-content img.size-full {
    max-width: none !important;
}

在你的循环中，而不是

   <?php the_post_thumbnail( $size, $attr ); ?>

while(have_posts()):the_post();
$orignalimage= wp_get_attachment_image_src(get_post_thumbnail_id(),\'full\');
$imageurl=$orignalimage[0];
//now to show the image you can use the html <img> tag
echo \'<img src="\'.$imageurl.\'"/>
//you can also give the height width and other parameters.
endwhile;

如果可以更改CSS，只需删除max_width 在.site-inner, .wrap 行（.site-inner,.wrap{margin:0 auto;max-width:1140px;}) 主题将适应大屏幕。

否则，请删除img 选择器来自embed, iframe, img, object, video, .wp-caption { max-width: 100%; } （至embed, iframe, object, video, .wp-caption { max-width: 100%; } ) 图像将以内联方式显示在width 的属性img 标签