some header changes

src/components/header.js

@@ -3,23 +3,35 @@ import React from "react"
 import logo from "../images/index/logo_white.png"
 import "bootstrap/dist/css/bootstrap.css"
 import "../styles/header.css"
+import { globalHistory as history } from '@reach/router'
 import {Navbar, Nav} from "react-bootstrap"
 import { Link } from '@reach/router'
 
-const NavLink = props => (
+const NavLink = ({ partial=true, ...props}) => (
   <Link
     {...props}
-    getProps={({ isCurrent }) => {
+    getProps={({isCurrent, isPartiallyCurrent }) => {
+      const isActive = partial
+        ? isPartiallyCurrent
+        : isCurrent;
       return {
         style: {
-          color: isCurrent ? "white" : "rgb(230, 221, 221)"
+          color: isActive ? "white" : ""
         }
       };
     }}
   />
 );
 
-const Header = ( ) => (
+const Header = (  ) => {
+  const { location } = history;
+  var active;
+  if  (location.pathname === "/projects/physics" ||
+       location.pathname === "/projects/education" ||
+       location.pathname === "/projects/math" ||
+       location.pathname === "/projects/software") 
+          { active = "active" } 
+  return(
     <header>
     <Navbar bg="dark" expand="lg" fixed="top">
     <div className="container">
@@ -27,14 +39,14 @@ const Header = ( ) => (
     <Navbar.Collapse id="basic-navbar-nav">
         <Nav className="mr-auto">
           <Navbar.Brand><Link to="/"><img src={logo} height="50px" alt="npm logo" id="logo"/></Link></Navbar.Brand>
-          <Nav.Link><NavLink to="/about">Группа</NavLink></Nav.Link>
-          <Nav.Link><NavLink to="/projects/physics">Проекты</NavLink></Nav.Link>
-          <Nav.Link><NavLink to="/partners">Партнеры</NavLink></Nav.Link>
+          <Nav.Link><NavLink to="about">Группа</NavLink></Nav.Link>
+          <Nav.Link><NavLink id={active} to="projects/physics">Проекты</NavLink></Nav.Link>
+          <Nav.Link><NavLink to="partners">Партнеры</NavLink></Nav.Link>
         </Nav>
     </Navbar.Collapse>
     </div>
     </Navbar>
   </header>
-)
+)}
 
 export default Header