/* This applies to 2 and 3, as before. */
section:not(:first-child) { margin-block-start: 4rem; }

/* But this negates/subtracts some of it. */
section:first-child { margin-block-end: -2rem; }

/* You can even pull things *out* from their bounds. */
section:nth-child(3) { margin-inline: -1rem; }
/* Note the logical shorthand! */