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About the <head>
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About CSS Preprocessors
CSS preprocessors help make authoring CSS easier. All of them offer things like variables and mixins to provide convenient abstractions.
It's a common practice to apply CSS to a page that styles elements such that they are consistent across all browsers. We offer two of the most popular choices: normalize.css and a reset. Or, choose Neither and nothing will be applied.
About Vendor Prefixing
To get the best cross-browser support, it is a common practice to apply vendor prefixes to CSS properties and values that require them to work. For instance -webkit- or -moz-.
We offer two popular choices: Autoprefixer (which processes your CSS server-side) and -prefix-free (which applies prefixes via a script, client-side).
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If the script you link to has the file extension of a preprocessor, we'll attempt to process it before applying.
let osoby=["Jan Nowak","Kazimierz Zyga","Stefan Koc","Ewa Mocek","Mariusz Abramski"];
/* Metoda .slice() wycina z tablicy jej fragment
od do wskazanego elementu. Zwraca wycięte elementy. */
/* Po użyciu .slice() NIE zmienia sie zawartość tablicy bazowej. */