Simple JavaScript Code for a simple task

I have a dropdown like this: <select class="form-select form-select--small" name="attribute[119]" id="attribute_119" required=""> <option value="">Choose Options</option> <option data-product-attribute-value="111" value="111">Plain (Not Decorated)</option> <option data-product-attribute-value="112" value="112">Animal</option> <option data-product-attribute-value="113" value="113">Bone</option> <option data-product-attribute-value="114" value="114">Bow</option> </select> Right after that, I have this: <div class="form-field" data-product-attribute="set-rectangle"> <label class="form-label form-label--alternate form-label--inlineSmall"> Animal Decorator Variations: <span data-option-value=""></span> ... <small>Required</small> </label> </div> <div class="form-field" data-product-attribute="set-rectangle"> <label class="form-label form-label--alternate form-label--inlineSmall"> Bone Decorator Variations: <span data-option-value=""></span> ... <small>Required</small> </label> </div> What I want, When Option Animal is selected in the dropdown, The div class="form-field" with Animal Decorator Variations should be visible and all other div class="form-field" should be hidden. Please write a JavaScript Code to do this. I cannot add an onChange attribute to the select option as I do not access to that code. All I can do is add a piece of JavaScript to that page. Will pay $25 for result within an hour.