Phthalo Blue (#000F89)

/* Background */
.element {
    background-color: #000F89;
}

/* Text */
.element {
    color: #000F89;
}

/* Border */
.element {
    border: 1px solid #000F89;
}

/* Linear gradient to complementary */
.element {
    background: linear-gradient(
        to right,
        #000F89,
        #897A00
    );
}

/* Radial gradient */
.element {
    background: radial-gradient(
        circle,
        #000F89,
        #897A00
    );
}

// SCSS variable
$phthalo-blue: #000F89;

// With RGB channels (useful for rgba() usage)
$phthalo-blue-r: 0;
$phthalo-blue-g: 15;
$phthalo-blue-b: 137;

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