Your link refers to the 'css' folder in your root which is wrong, it is public / then css / then custom.css -
<link href="{{ asset('/css/custom.css') }}" rel="stylesheet">
if you are making a call to the file from another page not in the root, use '../' to go back a folder -
<link href="{{ asset('../css/custom.css') }}" rel="stylesheet">
Tutorial is to be found at -
HTML and CSS File Structure[
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I noticed that you are making use of .scss files (SASS), note that you have to have Ruby installed for it to read and convert the styles properly to css but Ruby does not support newer files as of 2019, it will still read properly if within bounds prior to 2019, Dart Sass is now the standard -
[Sass] For Beginners: The Friendliest Guide About INSTALLING and USING Sass on Windows[
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