Путь к картинке прописан правильно и не подключается именно картинка, с цветом все ок.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<link rel="preconnect" href="https://fonts.gstatic.com">
<link href="https://fonts.googleapis.com/css2?family=Anton&family=Cardo:ital@1&family=Raleway:wght@400;600;700&display=swap" rel="stylesheet">
<link rel="stylesheet" type="text/css" href="css/main.css">
<title>Active Box</title>
</head>
<body>
<header class="header">
<div class="container">
<div class="header__inner">
<div class="header__logo">
<img src="img/logo.png" alt="">
</div>
<nav class="nav">
<a class="nav__link" href="#">Features</a>
<a class="nav__link" href="#">Works</a>
<a class="nav__link" href="#">Our Team</a>
<a class="nav__link" href="#">Testimonials</a>
<a class="nav__link" href="#">Download</a>
</nav>
</div>
</div>
</header>
<div class="intro">
</div>
</body>
</html>
body{
margin: 0;
font-size: 14px;
font-family: 'Raleway', sans-serif;
background: #fff;
background-color: #000;
}
*,*:before,*:after{
box-sizing: border-box;
}
.header{
position: absolute;
top: 0;
left: 0;
z-index: 1000;
width: 100%;
height: : 100px;
}
.container{
width: 100%;
max-width: 1170px;
margin: 0 auto;
}
.header__inner{
display: flex;
justify-content: space-between;
align-items: center;
padding: 35px 0;
border-bottom: 1px solid #fff;
}
.nav__link{
margin-left: 50px;
color: #fff;
opacity: 0.75;
text-decoration: none;
text-transform: uppercase;
transition: opacity 0.1s linear;
}
.nav__link:hover{
opacity:1;
}
.intro{
height: 750px;
background-image: url('../img/background.jpg');
}
Средний
(img1-отдельная папка в папке css)