.monstr-colors {
--color-face: #7986CB;
--color-nose: #9FA8DA;
--color-hair-right:#3949AB;
--color-hair-right2:#3949AB;
--color-hair-left:#3949AB;
--color-hair-left2:#3949AB;
--color-eye-right:#1A237E;
--color-pupil-right:#77006B;
--color-eye-left:#1A237E;
--color-pupil-left:#77006B;
--color-ellipse1:#9FA8DA;
--color-ellipse2:#7986CB;
--color-ellipse3:#C5CAE9;
}
.monstr-colors:hover {
--color-face: #3F8B4D;
--color-nose: #58C46C;
--color-hair-right:gold;
--color-hair-right2:#FFBB00;
--color-hair-left:gold;
--color-hair-left2:#FFBB00;
--color-eye-right:#77006B;
--color-pupil-right:#FF4151;
--color-eye-left:#77006B;
--color-pupil-left:#FF4151;
--color-ellipse1:#FFDD00;
--color-ellipse2:#C1A700;
--color-ellipse3:#FFEE7D;
}
<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" version="1.1" width="192" height="192" viewBox="0 0 48 48" >
<symbol id="monstr">
<rect width="100%" height="100%" fill="transparent" />
<path id="face" fill="var(--color-face)" d="M15.4,34.1L24,37l8.6-2.9c1.9-0.6,3-2.6,2.6-4.6L33,20H15l-2.2,9.5C12.3,31.5,13.5,33.5,15.4,34.1z"/>
<path id="nose" fill="var(--color-nose)" d="M29,30l-3-3h-4l-3,3v7c0,1.1,0.9,2,2,2h6c1.1,0,2-0.9,2-2V30z"/>
<path id="hair-right" fill="var(--color-hair-right)" d="M31,7c-0.5,0-1,0.4-1,1c0,0,0,0,0,0c-0.4,0-0.8,0.2-0.9,0.6c-0.2,0.5,0,1.1,0.6,1.3 C30,10.1,40,14.4,40,32.4V37c0,0.6,0.4,1,1,1s1-0.4,1-1v-4.6c0-14.4-6.1-20.7-9.5-23.1C35.9,10.3,44,14.7,44,34c0,0.6,0.4,1,1,1 s1-0.4,1-1C46,7.7,31.6,7,31,7z"/>
<path id="hair-right2" fill="var(--color-hair-right2)" d="M29.5,10.1c-0.5-0.3-1.1-0.1-1.3,0.4c-0.3,0.5-0.1,1.1,0.4,1.4c0.1,0,7.5,4.3,7.5,20.1v8c0,0.6,0.4,1,1,1 s1-0.4,1-1v-8C38,14.9,29.8,10.3,29.5,10.1z"/>
<path id="hair-left" fill="var(--color-hair-left)" d="M18.4,9.9c0.5-0.2,0.8-0.8,0.6-1.3C18.8,8.2,18.4,8,18,8c0,0,0,0,0,0c0-0.6-0.5-1-1-1C16.4,7,2,7.7,2,34 c0,0.6,0.4,1,1,1s1-0.4,1-1c0-19.6,8.1-23.8,11.6-24.7C12.2,11.6,6,17.9,6,32.4V37c0,0.6,0.4,1,1,1s1-0.4,1-1v-4.6 C8,14.4,18,10.1,18.4,9.9z"/>
<path id="hair-left" fill="var(--color-hair-left2)" d="M18.5,10.1C18.2,10.3,10,14.9,10,32v8c0,0.6,0.4,1,1,1s1-0.4,1-1v-8c0-15.8,7.4-20.1,7.5-20.1 c0.5-0.3,0.7-0.9,0.4-1.4C19.6,10,19,9.9,18.5,10.1z"/>
<path id="eye-right" fill="var(--color-eye-right)" d="M25,24.9c0,0,0.2,1.3,0.6,1.7s3.3,2.5,5.9-0.9c1.2-1.5,0.6-3.8,0.6-3.8S29.4,24.1,25,24.9z"/>
<circle id="pupil-right" cx="28" cy="25" r="1.5" fill="var(--color-pupil-right)" />
<path id="eye-left" fill="var(--color-eye-left)" d="M15.8,21.8c0,0-0.6,2.3,0.6,3.8c2.6,3.4,5.5,1.4,5.9,0.9c0.4-0.4,0.6-1.7,0.6-1.7 C18.6,24.1,15.8,21.8,15.8,21.8z"/>
<circle id="pupil-left" fill="var(--color-pupil-left)" cx="20" cy="25" r="1.5" fill="red" />
<ellipse id="ellipse1" fill="var(--color-ellipse1)" cx="24" cy="15" rx="12" ry="10"/>
<ellipse id="ellipse2" fill="var(--color-ellipse2)" cx="24" cy="13.8" rx="10" ry="7.8"/>
<ellipse id="ellipse3" fill="var(--color-ellipse3)" cx="24.2" cy="12.2" rx="8" ry="6.2"/>
</symbol>
<svg class="monstr-colors">
<use xlink:href="#monstr" />
</svg>
</svg>