Compiling .scss to css with grunt returns with weird error

So this is what I have inside of my grunt:

concat: {
      css: {
        src: [
          'assets/**.scss.liquid', 'assets/**.css'
        ],
        dest: 'assets/build.scss.liquid',
      }
    },
    sass: {
      dist: {
        options: {
          style: 'compressed',
          sourcemap: 'none',
          noCache: true
        },
        files: {
          'assets/build.css.liquid':'assets/build.scss.liquid'
        }
      }
    }

SCSS:

.all-collection {
  padding-top: 50px;
  height: 100%;
  width: 100%;
  color: white !important;
  justify-content: center;
  display: flex;

  p {
    color: white !important;
  }
}

This is what it returns after running grunt concat and grunt sass: Error: Invalid CSS after "50px": expected expression (e.g. 1px, bold), was ";" on line 2 of all-collection.scss

I tried removing the ; on the line it was specifying but the error just changed to the next line that has ;. Not sure why it's giving this error.

Solved by switching plugins. I'm using grunt-sass instead.