Lipschitz regularity for orthotropic functionals with general growth

We study the local Lipschitz regularity of local minimizers for a class of degenerate orthotropic functionals with $\varphi$-growth, where $\varphi$ is a general N-function. Unlike standard isotropic functionals, the ellipticity of the associated Euler-Lagrange equation degenerates separately in each coordinate direction, presenting significant anisotropic difficulties. Furthermore, the general N-function setting lacks the algebraic scale invariance available in the classical orthotropic $p$-Laplacian case. Despite these structural difficulties, we prove that local minimizers are locally Lipschitz continuous. Our approach relies on a regularized approximation scheme, mixed-direction Caccioppoli inequalities, and a carefully designed Moser-type iteration that incorporates an interpolation argument to bridge the gaps between consecutive integrability exponents.