styled component doesn't work with hierachy selectors - css

Question

I'm learning to use styled components,but it looks like when i target css classes in hierarchy,it doesn't seem to work.Here i'm using i would like to make apply some styles wheneve use hovers on navigations links.
Here is my navbar code :
import React from "react";
import { Nav, Navbar } from "react-bootstrap";
import Flag from "../common/Image";
import styled from "styled-components";
import NavLink from "../common/NavLink";
const imageURL = "/static/img/abc.png";
const Navigation = ({ className }) => {
return (
<Navbar className={className} collapseOnSelect expand="lg" variant="light">
<Navbar.Brand href="#home">
<Flag imageSource={imageURL} size={[80, 70]} />
</Navbar.Brand>
<NavLink linkName="A" URL={"#"} />
<Navbar.Toggle aria-controls="responsive-navbar-nav" />
<Navbar.Collapse id="responsive-navbar-nav">
<Nav className="mr-auto">
<NavLink linkName="B" URL={"#a"} />
<NavLink linkName="C" URL={"#b"} />
<NavLink linkName="D" URL={"#b"} />
</Nav>
<Nav>
<NavLink linkName="Espace de discussion" URL={"#discussions"} />
<NavLink linkName="Contactez-nous" URL={"#contact"} />
<Nav.Link>
<i clasName="fas fa-envelope" />
</Nav.Link>
<Nav.Link>
<i className="fas fa-bell" />
</Nav.Link>
<Nav.Link>
<i className="fas fa-user-circle" />
</Nav.Link>
</Nav>
</Navbar.Collapse>
</Navbar>
);
};
export default styled(Navigation)`
background-color: white;
border-bottom: 1px solid #e4e8f0;
`;
And my NavLink component
import React from "react";
import styled from "styled-components";
import { Nav } from "react-bootstrap";
import PropTypes from "prop-types";
const NavLink = ({ linkName, URL, className }) => {
return (
<Nav.Link className={className} href={URL}>
{linkName}
</Nav.Link>
);
};
NavLink.PropTypes = {
linkName: PropTypes.string,
URL: PropTypes.string
};
export default styled(NavLink)`
cursor: pointer;
color: green;
transition: 0.4s linear;
padding: 10px;
&:hover {
color: white;
font-size: 90;
background-color: #2e384d;
border-radius: 10px;
}
.navbar-light .navbar-nav .nav-link &:hover {
color: white;
}
`;
I the bellow gif,the animation is for changind links styled is working for all the links,but the color is only changing to white for the A link.But the form other background,border are changing but not the link color.Here the behaviour:
When i use the following code : .navbar-light .navbar-nav .nav-link &:hover {
color: white;
} in a normal css file without using styled component i get the good the exptected behavior.For solving i tried to use sass way of doing in the definition of my styled component like this :
.navbar-light {
.navbar-nav {
.nav-link {
&:hover {
color: white;
}
}
}
}
But nothing changes.How can i do for making all links text become white with styled-compont definition?

Answer 1

Alright, because of how <Nav> is wrapping your <NavLink>, the nav-link className has a higher specificity than your styled component className (the NavLink component is applying the styled component className before "nav-link" and, as a result, doesn't override the Bootstrap CSS). For example, the className looks like: "sc-lhVmIH gcJAof nav-link", where the styled component className: "sc-lhVmIH gcJAof" is being overridden by the last applied className "nav-link". There are several solutions to fix this, as shown below.
Solutions
Simply add color: white !important; in the styled NavLink:
export default styled(NavLink)`
cursor: pointer;
color: green;
transition: 0.4s linear;
padding: 10px;
border-radius: 10px;
&:hover {
color: white !important;
font-size: 90;
background-color: #2e384d;
border-radius: 10px;
}
`;
In Navigation, where <NavBar className={className}>...</NavBar> accepts a styled component className, add the following css to override the Bootstrap CSS stylesheet:
export default styled(Navigation)`
background-color: white;
border-bottom: 1px solid #e4e8f0;
&.navbar-light {
& .navbar-nav {
& .nav-link:hover {
color: white;
}
}
}
`;
Import the Bootstrap less into a less file and override the nav-link:hover className.
CSS Specificity
Here's how the CSS specificity is being applied to the DOM:
Demos
Click here for a working demo.
Working codesandbox (contains solution #1 and #2 -- you'll only need to use one of them, not both):