3 ANIMATION_DELAY
=$
(bc <<EOF
4 $(cat _face_delay) + 0.2
9 <div class="stem" style="animation-delay: ${ANIMATION_DELAY}s;"></div>
12 STEM_APPEAR_DURATION
=0.6 # must match animation-duration in chryzantem.html.template
15 $ANIMATION_DELAY + $STEM_APPEAR_DURATION