Check out example codes for "eliminate border white around components angular". It will help you in understanding the concepts better.

Code Example 1

// if a white border appears in all the components that you add to the page 
//make sure you have this code in src/styles.scss
//(this file the global file of styles for the entire project)

body {
    border: none !important;
    margin: 0px !important;
    padding: 0 !important;

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