Celestial Blue (#4997D0)

/* Background */
.element {
    background-color: #4997D0;
}

/* Text */
.element {
    color: #4997D0;
}

/* Border */
.element {
    border: 1px solid #4997D0;
}

/* Linear gradient to complementary */
.element {
    background: linear-gradient(
        to right,
        #4997D0,
        #EFCBB2
    );
}

/* Radial gradient */
.element {
    background: radial-gradient(
        circle,
        #4997D0,
        #EFCBB2
    );
}

// SCSS variable
$celestial-blue: #4997D0;

// With RGB channels (useful for rgba() usage)
$celestial-blue-r: 73;
$celestial-blue-g: 151;
$celestial-blue-b: 208;

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