XRISM Resolve spectra synthesized from model B18.3-Dec at three epochs: 2024 (left panels), 2027 (center panels), and 2037 (right panels). The figure presents close-up views of selected emission lines: Si XIV (2.1 keV), S XV (2.46 keV), Ar XVII (3.14 keV), Fe XXV (6.7 keV). Each panel shows the synthetic spectra of SN 1987A as observed with XRISM Resolve (shown as gray crosses), assuming an exposure time of 500 ks. Also included are the ideal synthetic spectra (black lines) and the contributions from different plasma components: shocked CSM (blue), shocked H envelope (green), and shocked pure ejecta (violet). The total contribution from shocked ejecta (H envelope + pure ejecta) is highlighted by the shaded yellow region. The top axis of each panel indicates the corresponding Doppler shift velocities relative to the rest-frame wavelength of each line.