Before customizing the height and width of an element in Moodle on-premises with CSS, we need to locate the information of said element. It is not a very difficult task because we have already been working with similar information. Therefore, we need to enter Moodle on-premises's site and proceed with the following steps:
Right-click on the logo and click on Inspect, as shown in the following screenshot:
Information about the element appears, as shown in the following screenshot:
The following code appears, highlighted in the previous screenshot; it reads as follows:
<a class="logo" href="//localhost" id="yui_3_17_2_1_1468231690835_326"></a>
The following code defines the element and its style:
#page-header a.logo
The height is 158px and its width is 200px. The information is shown highlighted in the following screenshot: