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HTML 

              
                mixin cross()
  svg.x(class!=attributes.class style!=attributes.style viewBox="0 0 100 100")
    path(d="M 80 20 L 20 80" stroke-dasharray="100" stroke-width="10" stroke-linecap="round")
    path(d="M 20 20 L 80 80" stroke-dasharray="100" stroke-width="10" stroke-linecap="round")
mixin naught()
  svg.o(class!=attributes.class style!=attributes.style viewBox="0 0 100 100")
    circle(r="30" cx="50" cy="50" stroke-dasharray="200" stroke-width="10" stroke-linecap="round" fill="none")
form.game
  - for (let i = 0; i < 9; i++)
    - const x = i % 3
    - const y = Math.floor(i / 3)
    input(type='checkbox' id=`x-${i}`)
    +cross()(class="game__piece" style=`--x: ${x}; --y: ${y}`)
    input(type='checkbox' id=`o-${i}`)
    +naught()(class="game__piece" style=`--x: ${x}; --y: ${y}`)
  .board
    - const DELAYS = [0, 3, 1, 2]
    - for (let l = 0; l < 4; l++)
      - const rotate = l % 2
      - const shift = 2 % (l + 1) ? 1 : -1
      svg.board__line(viewBox="0 0 10 300" style=`--rotate: ${rotate}; --shift: ${shift}; --delay: ${DELAYS[l]};`)
        path(d="M 5 5 L 5 295" stroke-dasharray="300" stroke-width="10" stroke-linecap="round")
    - for (let i = 0; i < 9; i++)
      .board__cell
        label(for=`x-${i}`)
          +cross()(class="ghost")
        label(for=`o-${i}`)
          +naught()(class="ghost")
  .game__result.game__result--x.result
    .result__content
      .result__title X Wins!
      +cross()(class="result__winner")
  .game__result.game__result--o.result
    .result__content
      .result__title O Wins!
      +naught()(class="result__winner")
  .game__result.game__result--draw.result
    .result__content
      .result__title Draw...
  button(type="reset" title="Reset Board")
    svg.reset(viewBox="0 0 24 24")
      path(d="M17.65,6.35C16.2,4.9 14.21,4 12,4A8,8 0 0,0 4,12A8,8 0 0,0 12,20C15.73,20 18.84,17.45 19.73,14H17.65C16.83,16.33 14.61,18 12,18A6,6 0 0,1 6,12A6,6 0 0,1 12,6C13.66,6 15.14,6.69 16.22,7.78L13,11H20V4L17.65,6.35Z")
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CSS 

              
                @font-face
  font-family Cyber
  src url("https://assets.codepen.io/605876/Blender-Pro-Bold.otf")
  font-display swap

*
  box-sizing border-box

:root
  --size 50vmin
  --cell-size calc(var(--size) / 3)
  --bg hsl(210, 50%, 15%)
  --cross hsl(280, 80%, 70%)
  --naught hsl(150, 80%, 70%)
  --line hsl(0, 0%, 90%)
  --draw-speed 0.2s

@media(prefers-reduced-motion)
  :root
    --draw-speed 0s
    
body
  background var(--bg)
  min-height 100vh
  display grid
  place-items center
  margin 0
  font-family 'Cyber', sans-serif
  overflow hidden
  color var(--line)

label
  position absolute
  height 100%
  width 100%

input
  position fixed
  left 100%

button
  position absolute
  top 125%
  background transparent
  appearance none
  cursor pointer
  height 5vmin
  width 5vmin
  min-height 48px
  min-width 48px
  border 0
  outline transparent
  padding 0
  left 50%
  transform translate(-50%, 0)
  transition transform var(--draw-speed)

  svg
    stroke none
    stroke-width 0

  &:hover
    transform translate(-50%, -4%)

  &:active
    transform translate(-50%, 2%) scale(0.8)

svg
  filter drop-shadow(0 0 1vmin var(--stroke)) brightness(1.2)
  stroke var(--stroke, black)

circle
path
  animation draw var(--draw-speed) calc(var(--delay, 0) * var(--draw-speed)) ease-in both

path:nth-of-type(2)
  --delay 1

@keyframes draw
  to
    stroke-dashoffset 0

.game
  position relative

  &__piece
    display none
    position absolute
    left calc(var(--x) * var(--cell-size))
    top calc(var(--y) * var(--cell-size))

  &__result
    display none
    position absolute
    width calc(var(--size) * 1.5)
    height calc(var(--size) * 1.5)
    transform translate(-50%, -50%)
    top 50%
    left 50%

.result
  z-index 10
  backdrop-filter blur(25px)

  &__content
    animation flyIn var(--draw-speed) var(--draw-speed) ease-in backwards
    height 40%
    width 40%
    position absolute
    top 50%
    left 50%
    transform translate(-50%, -50%)
    border-radius 15%
    background hsla(210, 30%, 20%, 0.8)
    align-items center
    display flex
    justify-content center
    flex-direction column
    font-weight bold
    font-size 2rem
    box-shadow 0 3vmin 2.5vmin -2.5vmin hsl(0, 0%, 0%)

@keyframes flyIn
  0%
    transform translate(-50%, 150%) scale(0)
    opacity 0


.reset
  height 100%
  fill var(--line)


.board
  height var(--size)
  width var(--size)
  display grid
  grid-template-columns repeat(3, 1fr)
  grid-template-rows repeat(3, 1fr)
  place-items center

  &__line
    --stroke var(--line)
    position absolute
    height var(--size)
    width calc(var(--size) * 0.05)
    left 50%
    top 50%
    transform translate(-50%, -50%) rotate(calc(var(--rotate, 0) * -90deg)) translateX(calc(var(--shift, 0) * ((var(--size) / 3) * 0.5)))

    path
      stroke-dashoffset 300

  &__cell
    height var(--cell-size)
    position relative
    width var(--cell-size)

.o
.x
  height var(--cell-size)
  width var(--cell-size)
  z-index 2

.o
  --stroke var(--naught)
  transform rotateX(180deg)

  circle
    stroke-dashoffset 200

.x
  --stroke var(--cross)
  stroke-dashoffset 100


:checked + *
  display block

// Game mechanism
:checked ~ .board .board__cell label:nth-of-type(odd)
:checked ~ :checked ~ .board .board__cell label:nth-of-type(even)
:checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(odd)
:checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(even)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(odd)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(even)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(odd)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(even)
  display block

:checked ~ .board .board__cell label:nth-of-type(even)
:checked ~ :checked ~ .board .board__cell label:nth-of-type(odd)
:checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(even)
:checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(odd)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(even)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(odd)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(even)
:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ .board .board__cell label:nth-of-type(odd)
  display none

#x-0:checked ~ #x-1:checked ~ #x-2:checked ~ .game__result--x
#x-3:checked ~ #x-4:checked ~ #x-5:checked ~ .game__result--x
#x-6:checked ~ #x-7:checked ~ #x-8:checked ~ .game__result--x
#x-0:checked ~ #x-3:checked ~ #x-6:checked ~ .game__result--x
#x-1:checked ~ #x-4:checked ~ #x-7:checked ~ .game__result--x
#x-2:checked ~ #x-5:checked ~ #x-8:checked ~ .game__result--x
#x-0:checked ~ #x-4:checked ~ #x-8:checked ~ .game__result--x
#x-2:checked ~ #x-4:checked ~ #x-6:checked ~ .game__result--x
#o-0:checked ~ #o-1:checked ~ #o-2:checked ~ .game__result--o
#o-3:checked ~ #o-4:checked ~ #o-5:checked ~ .game__result--o
#o-6:checked ~ #o-7:checked ~ #o-8:checked ~ .game__result--o
#o-0:checked ~ #o-3:checked ~ #o-6:checked ~ .game__result--o
#o-1:checked ~ #o-4:checked ~ #o-7:checked ~ .game__result--o
#o-2:checked ~ #o-5:checked ~ #o-8:checked ~ .game__result--o
#o-0:checked ~ #o-4:checked ~ #o-8:checked ~ .game__result--o
#o-2:checked ~ #o-4:checked ~ #o-6:checked ~ .game__result--o
  display block

  ~ .game__result--draw
    display none

:checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked ~ :checked
  ~ .game__result--draw
    display block

.ghost
  opacity 0
  transition opacity var(--draw-speed)

  circle
  path
    animation none
    stroke-dashoffset 0

label:hover .ghost
  opacity 0.25
!

JS
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999px

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