Click to "Show Description" with JavaScript and HTML

Hey gang, I am trying to format variables in a question that have a "Show Description" link that, when clicked, expands the variable to show the definition. I have the code below and it works in Safari, but it DOESN'T work in Chrome/Mozilla/Edge/Explorer. Essentially, I want the variable to look like "Coffee (Show Description)" and when you click it, the variable expands to show "Coffee (Hide Description) Delicious bean juice." ! Can you help? Best, T