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Stellar dynamics provides one of the most robust ways of measuring dark-matter distributions in galaxies. We develop a novel triaxial dynamical model with the minimum assumption that the system is stationary and apply it to the MW halo stars with 6D position-velocity measured by Gaia + LAMOST. We thus robustly constrain the 3D distribution of the MW dark-matter halo. Surprisingly, we find that the MW dark-matter halo is vertically aligned with the stellar disk, and in alignment with the prominent satellite plane, this reveals a flip of the Galactic disk caused by minor mergers. Such 3D dark-matter distribution can only be uncovered for the MW, for nearby galaxies, we measure the DM mass within ~5Re for about 100 galaxies combining MaNGA IFU data and HI spectra from FAST. We will show that a large fraction of massive galaxies have significantly lower DM mass than the prediction of cosmological simulations, even extending to 5Re.