About Rothko and abstract art in general. If you are curious about how to perceive abstract art (not to love, namely to understand what it is, where the legs grow and how to look at it), then I advise you to read Kandinsky's "Point and line on the plane", he was a very thinking artist and theorist of art and in this little book dismantled the emotional perception of the simplest elements of the image. It is useful for viewers and artists of any direction (the theory of composition is greatly disassembled). He has a little about the color, but in general it needs to read Malevich.
Kandinsky will not explain why some specimens are stooled, painted onto the canvas and applied to it bulks, but the art of the 20th century will become a little more understandable.