T1 215px 1fr
a
b
T2 repeat(3,1fr) gap 30
a
b
c
T3 placement
a
b
c
T4 ::after line
a
b
T5 auto-fill minmax(150,1fr)
a
b
c
d
e
T6 rows + row-gap
a
b
c
d
T7 25% 75%
a
b
running...