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CSS CSS Transitions and Transforms Transition Timing Functions and Delays Timing Functions and Delays Challenge

Timing Functions and Delays Challenge Assistance


I'm trying to perform the first challenge on this question which is asking me; "Using the shorthand, transition the flex-grow property of .nav-item over .5 seconds".

I've written the following and in the preview it's functioning as I expect with the buttons' transition occurring on a 0.5 second delay however the challenge isn't accepting my answer.

Could someone please point me in the right direction as I think I'm not understanding exactly what's being asked of me.

Thank you in advance.

/* nav-item transitions ---------- */

.nav-item {
    flex-grow: 1;
  transition-duration: 0.5s;

.nav-item:hover {
    flex-grow: 2;

/* nav icon transitions ---------- */

.icon {
  right: -25px;

.nav-item:hover .icon {
    right: 12%;
<!DOCTYPE html>
    <title>CSS Transitions</title>
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
    <link rel="stylesheet" href="page.css">
    <link rel="stylesheet" href="style.css">
    <div class="container">

        <nav class="nav">
            <a class="nav-item" href="#">About <i class="icon material-icons">person</i></a>
            <a class="nav-item" href="#">Work <i class="icon material-icons">work</i></a>


Never mind, with a little searching online I figured out that I needed to target the specific transition "flex-grow".

For anyone looking for the answer, 'transition-duration: 0.5s;' in the CSS file above becomes: "transition: flex-grow 0.5s;"

Hopefully this helps get someone else unstuck in the future.

1 Answer

Steven Parker
Steven Parker
229,644 Points

You're right, the challenge was specifically asking that you do this "Using the shorthand" property (transition). Also, if you don't specify the transition-property, either directly or with the shorthand, the transition will be performed on all applicable properties instead of just the intended one.