How to give or apply css to Ordered list Numbers

HTML Ordered List:

<ol class="mylist">
              <li>Fist list item</li>
              <li>Second list item</li>
              <li>Third list item</li>
              <li>Fourth list item</li>
              <li>Fifth list item</li>
              <li>Sixth list item</li>
              <li>Seventh list item</li>
</ol>

CSS Styles:

<style>
.mylist{     list-style-type: none;    counter-reset: numbers;    }
.mylist > li:before { content: counter(numbers); counter-increment: numbers; }
</style>
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