Simulated transmission spectrum of the medium CH₄ scenario with the H₂-dominated atmosphere (scenario 1b) binned to a constant resolving power of R = 300 (maximum resolving power of JWST NIRSpec PRISM at 5 μm). The black line represents the spectrum that includes the contribution from all gases which are considered in 1D-TERRA and also available in HITRAN, Rayleigh scattering, aerosol extinction, H₂O CKD, and CIAs. Individual gaseous absorption of selected molecules are represented by different colors.