Formulated as a quantum field theory.
Quarks, Gluon flux tubes, Strong Nuclear Force, & Quantum Chromodynamics by Physics Videos by Eugene Khutoryansky (2018)
. Source. Some decent visualizations of how the field lines don't expand out like they do in electromagnetism, suggesting color confinement.PHYS 485 Lecture 6: Feynman Diagrams by Roger Moore (2016)
. Source. Despite the title, this is mostly about QCD.