.container {
    display: grid;
    grid-template-areas:
        'header header'
        'sidebar content'
        'footer footer';
    grid-gap: 10px;
}

.header { grid-area: header; }
.sidebar { grid-area: sidebar; }
.content { grid-area: content; }
.footer { grid-area: footer; }

.element {
    background: url('image.jpg');
    mix-blend-mode: multiply;
}

.element {
    filter: blur(5px) brightness(150%);
}