Customize CSS for hover to underline

Can someone help me update my CSS so that when I hover over the menu navigation panel on my mobile, the underline is only under the words, and not the entire screen?

This is my current code, and this is what it looks like: 

.header-menu-nav-item { position: relative; }
.header-menu-nav-item::before { content: ""; position: absolute; display: inline-block; width: 100%; height: 3px; bottom: 0; left: 0; background-color: red; transform: scaleX(0); transition: transform 0.3s ease; }
.header-menu-nav-item:not(.header-menu-nav-item--active):hover::before { transform: scaleX(1); }

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