import panel as pn
pn.extension()

import random

rcolor = lambda: "#%06x" % random.randint(0, 0xFFFFFF)

box = pn.FlexBox(*[pn.pane.HTML(str(i), background=rcolor(), width=100, height=100) for i in range(24)])
box

column_box = box.clone(flex_direction='column', height=450)
column_box

column_box.clone(align_content='space-evenly')

color = pn.pane.HTML(str(5), background=rcolor(), width=100, height=100)
column_box[5] = color

column_box