Mapping of the Material Design Shadow suggestions - https://material.io/guidelines/resources/shadows.html

material-shadow.scss

/* rem unit setup based on 
:root {
  font-size: 10px;
}
*/
/// @example
///   .foo { box-shadow: material-shadow(dp3); }
@function material-shadow($elevation) {
  $umbra: rgba(black, .14);
  $penumbra: rgba(black, .12);
  $ambient: rgba(black, .2);
  
  $elevations: (
    dp1: (0 0 .3rem $umbra,     0 .2rem .2rem $penumbra, 0 .1rem .2rem $ambient),
    dp2: (0 0 .4rem $umbra,     0 .3rem .4rem $penumbra, 0 .1rem .5rem $ambient),
    dp3: (0 .3rem .3rem $umbra, 0 .3rem .4rem $penumbra, 0 .1rem .8rem $ambient),
    dp4: (0 .2rem .4rem $umbra, 0 .4rem .5rem $penumbra, 0 .1rem 1rem $ambient),
    
    dp6: (0 .6rem 1rem $umbra,  0 .1rem 1.8rem $penumbra, 0 .3rem .5rem $ambient),
    
    dp8: (0 .8rem 1rem .1rem $umbra,   0 .3rem 1.4rem .3rem $penumbra, 0 .4rem 1.5rem $ambient),
    dp9: (0 .9rem 1.2rem .1rem $umbra, 0 .3rem 1.6rem .2rem $penumbra, 0 .5rem .6rem $ambient),
    
    dp12: (0 1.2rem 1.7rem .2rem $umbra, 0 .5rem 2.2rem .4rem $penumbra, 0 .7rem .8rem $ambient),
    dp16: (0 1.6rem 2.4rem .2rem $umbra, 0 .6rem 3rem .5rem $penumbra,   0 .8rem 1rem $ambient),
    dp24: (0 2.4rem 3.8rem .3rem $umbra, 0 .9rem 4.6rem .8rem $penumbra, 0 1.1rem 1.5rem $ambient)
  );
  
  @return map-get($elevations, $elevation);
}