Black Olive (#3B3C36)

/* Background */
.element {
    background-color: #3B3C36;
}

/* Text */
.element {
    color: #3B3C36;
}

/* Border */
.element {
    border: 1px solid #3B3C36;
}

/* Linear gradient to complementary */
.element {
    background: linear-gradient(
        to right,
        #3B3C36,
        #383642
    );
}

/* Radial gradient */
.element {
    background: radial-gradient(
        circle,
        #3B3C36,
        #383642
    );
}

// SCSS variable
$black-olive: #3B3C36;

// With RGB channels (useful for rgba() usage)
$black-olive-r: 59;
$black-olive-g: 60;
$black-olive-b: 54;

// Usage
.element {
    background-color: $black-olive;
    color: rgba($black-olive-r, $black-olive-g, $black-olive-b, 0.8);
}