When building mobile-friendly web pages, you may come across long links in your content that cause horizontal scrollbars on smaller screens. Since links don’t contain spaces, there is no natural break for them to wrap when their parent container shrinks in width. You can use the following CSS rule to fix this:

a {
    /* standard syntax for modern browsers */
    overflow-wrap: break-word;
    /* older browser syntax */
    word-wrap: break-word; 

A better approach is to change the text of the link itself. Instead of having http://some/really/long/link?withabunchoftextinit, you can just link an appropriate keyword or two. Better for SEO and better for users.