我想在css中更改svg图标的颜色，但由于某种原因它不会更改。请帮忙:https://codepen.io/Flowersj/pen/OJExzME
我试着添加类到父标签，并试图样式它，没有工作。
HTML:<svg class="navigation-icon" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="16" height="16"><path fill="none" d="M0 0h24v24H0z"/><path d="M18.031 16.617l4.283 4.282-1.415 1.415-4.282-4.283A8.96 8.96 0 0 1 11 20c-4.968 0-9-4.032-9-9s4.032-9 9-9 9 4.032 9 9a8.96 8.96 0 0 1-1.969 5.617zm-2.006-.742A6.977 6.977 0 0 0 18 11c0-3.868-3.133-7-7-7-3.868 0-7 3.132-7 7 0 3.867 3.132 7 7 7a6.977 6.977 0 0 0 4.875-1.975l.15-.15z" fill="rgba(0,0,0,1)"/></svg>
CSS:.navigation-icon { fill: red; }
需要将类分配给路径，而不是svg容器。
body {
background-color: black;
}
.nav-icon-path {
fill: red;
}<body>
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="16" height="16">
<path fill="none" d="M0 0h24v24H0z"/>
<path class="nav-icon-path" d="M18.031 16.617l4.283 4.282-1.415 1.415-4.282-4.283A8.96 8.96 0 0 1 11 20c-4.968 0-9-4.032-9-9s4.032-9 9-9 9 4.032 9 9a8.96 8.96 0 0 1-1.969 5.617zm-2.006-.742A6.977 6.977 0 0 0 18 11c0-3.868-3.133-7-7-7-3.868 0-7 3.132-7 7 0 3.867 3.132 7 7 7a6.977 6.977 0 0 0 4.875-1.975l.15-.15z" fill="rgba(0,0,0,1)"/>
</svg>
</body>您仍然可以在svg容器上放置一个类，甚至可以将其用于悬停:
body {
background-color: black;
}
.navigation-icon > .nav_icon_path {
fill: red;
}
.navigation-icon:hover {
cursor: pointer;
}
.navigation-icon:hover > .nav_icon_path {
fill: yellow;
}<body>
<svg class="navigation-icon" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="16" height="16">
<path fill="none" d="M0 0h24v24H0z"/>
<path class="nav_icon_path" d="M18.031 16.617l4.283 4.282-1.415 1.415-4.282-4.283A8.96 8.96 0 0 1 11 20c-4.968 0-9-4.032-9-9s4.032-9 9-9 9 4.032 9 9a8.96 8.96 0 0 1-1.969 5.617zm-2.006-.742A6.977 6.977 0 0 0 18 11c0-3.868-3.133-7-7-7-3.868 0-7 3.132-7 7 0 3.867 3.132 7 7 7a6.977 6.977 0 0 0 4.875-1.975l.15-.15z" fill="rgba(0,0,0,1)"/>
</svg>
</body>AtomicUs是对的，您需要定位您的路径而不是svg元素，因为svg元素没有fill属性。在这个特定的svg中，您还可以删除空路径，因为它是冗余的，然后针对父导航图标的path子路径svg:
.navigation-icon path {
fill: red;
}<svg class="navigation-icon" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="16" height="16">
<path d="M18.031 16.617l4.283 4.282-1.415 1.415-4.282-4.283A8.96 8.96 0 0 1 11 20c-4.968 0-9-4.032-9-9s4.032-9 9-9 9 4.032 9 9a8.96 8.96 0 0 1-1.969 5.617zm-2.006-.742A6.977 6.977 0 0 0 18 11c0-3.868-3.133-7-7-7-3.868 0-7 3.132-7 7 0 3.867 3.132 7 7 7a6.977 6.977 0 0 0 4.875-1.975l.15-.15z" fill="rgba(0,0,0,1)"/>
</svg>您可以在路径上使用fill="currentColor"，然后您可以使用color属性为svg设置样式:
.red {
color: red;
}
.blue {
color: blue;
}<svg class="red" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="16" height="16">
<path d="M18.031 16.617l4.283 4.282-1.415 1.415-4.282-4.283A8.96 8.96 0 0 1 11 20c-4.968 0-9-4.032-9-9s4.032-9 9-9 9 4.032 9 9a8.96 8.96 0 0 1-1.969 5.617zm-2.006-.742A6.977 6.977 0 0 0 18 11c0-3.868-3.133-7-7-7-3.868 0-7 3.132-7 7 0 3.867 3.132 7 7 7a6.977 6.977 0 0 0 4.875-1.975l.15-.15z" fill="currentColor"/>
</svg>
<svg class="blue" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" width="16" height="16">
<path d="M18.031 16.617l4.283 4.282-1.415 1.415-4.282-4.283A8.96 8.96 0 0 1 11 20c-4.968 0-9-4.032-9-9s4.032-9 9-9 9 4.032 9 9a8.96 8.96 0 0 1-1.969 5.617zm-2.006-.742A6.977 6.977 0 0 0 18 11c0-3.868-3.133-7-7-7-3.868 0-7 3.132-7 7 0 3.867 3.132 7 7 7a6.977 6.977 0 0 0 4.875-1.975l.15-.15z" fill="currentColor"/>
</svg>