About customize.css

Customize.css is a small css file that improves user agent stylesheet values
so that browsers display all elements more consistently & in compliance with modern standards.

For example:

h1 {
   font-size: 2.2em;
}


a {
   text-decoration: none;
   user-select: none;
}


p { color: #666; }


ul, ol {
   margin: 0;
   padding: 0;
}

Features customize.css

The advantages of customize.css are very many, and this is evident from the following:

One of the most important features that are not present in the frameworks and that many developers and programmers do
not know is the ability to change the shape of the scroll bar, which gives an attractive appearance to customers.

::-webkit-scrollbar {
   width: 10px;
   height: 5px;
}


::-webkit-scrollbar-track {
   background: var(--main-background, #fff);
}


::-webkit-scrollbar-thumb {
   background: var(--main-color, #07f);
}


::-webkit-scrollbar-thumb:hover {
   border: 1px solid #fff;
}

Another advantage is the addition of features to some elements that must be placed each time you create a site, which reduces the time required to create the site, and these features include:

form input:not([type="submit"]) {
   padding: 10px 50px 10px 10px;
   caret-color: var(--main-color, #07f);
}


[type="submit"] {
   padding: 10px;
   cursor: pointer;
   text-transform: capitalize;
}


form input:not([type="submit"]):focus,
[type="submit"]:focus {
   outline: 0;
}


textarea {
   resize: none;
}

Customize vs Normalize vs Reset

customize.css, of course, overcomes normalize and reset, because customize has all the properties of normalize and reset, in addition to other properties, and it does not have a lot of annoying commints that increase the file space



Browser support

customize.css supports this browsers