@import url("https://fonts.googleapis.com/css2?family=Inter:wght@500;650;800&display=swap");

:root {
  --paper: #f4f1ea;
  --surface: #fbf8f1;
  --ink: #24231f;
  --muted: #8b8478;
  --line: #d8d0c3;
  --slice: rgba(36, 35, 31, 0.13);
  --target-slice: rgba(36, 35, 31, 0.075);
  --shadow: rgba(46, 39, 30, 0.11);
}

* {
  box-sizing: border-box;
}

html,
body {
  width: 100%;
  height: 100%;
  margin: 0;
}

body {
  display: grid;
  place-items: center;
  overflow: hidden;
  background: var(--paper);
  color: var(--ink);
  font-family: Inter, system-ui, sans-serif;
}

.game {
  position: relative;
  width: min(92vw, 430px);
  min-height: 660px;
  display: grid;
  grid-template-rows: auto auto auto 58px auto;
  justify-items: center;
  align-content: center;
  gap: 22px;
  padding: 42px 32px 34px;
  text-align: center;
  user-select: none;
}

.help {
  position: absolute;
  top: 28px;
  right: 28px;
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 14px;
  font-weight: 800;
  cursor: pointer;
  transition: border-color 160ms ease, color 160ms ease;
}

.help:hover,
.help:focus-visible,
.help[aria-expanded="true"] {
  color: var(--ink);
  border-color: var(--ink);
  outline: none;
}

.tooltip {
  position: absolute;
  top: 70px;
  right: 28px;
  z-index: 20;
  width: min(280px, calc(100vw - 56px));
  padding: 14px 15px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: var(--surface);
  box-shadow: 0 18px 44px var(--shadow);
  text-align: left;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-6px);
  transition: opacity 140ms ease, transform 140ms ease, visibility 140ms ease;
}

.tooltip.open,
.help:hover + .tooltip,
.help:focus-visible + .tooltip {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.tooltip::before {
  content: "";
  position: absolute;
  top: -6px;
  right: 14px;
  width: 10px;
  height: 10px;
  border-left: 1px solid var(--line);
  border-top: 1px solid var(--line);
  background: var(--surface);
  transform: rotate(45deg);
}

.tooltip strong {
  display: block;
  margin-bottom: 7px;
  font-size: 13px;
  font-weight: 800;
}

.tooltip span {
  display: block;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.45;
}

.target {
  display: grid;
  justify-items: center;
  gap: 8px;
}

.target p,
.summary-label {
  margin: 0;
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.target h1 {
  margin: 0;
  font-size: clamp(5.4rem, 20vw, 8.8rem);
  font-weight: 800;
  line-height: 0.78;
  letter-spacing: 0;
}

.fraction {
  display: inline-flex;
  align-items: baseline;
  gap: 0.085em;
  font-variant-numeric: tabular-nums;
}

.fraction__slash {
  margin-inline: 0.035em;
  font-weight: 650;
  opacity: 0.85;
  transform: translateY(-0.02em);
}

.instruction {
  height: 18px;
  margin: 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 18px;
}

.board {
  width: min(76vw, 330px);
  display: block;
  overflow: visible;
  cursor: crosshair;
  touch-action: none;
}

.disc {
  fill: var(--surface);
  stroke: var(--ink);
  stroke-width: 1.25;
  filter: drop-shadow(0 18px 22px var(--shadow));
  transition: opacity 180ms ease;
}

.disc.faded {
  opacity: 0.28;
}

.parts {
  pointer-events: none;
}

.part {
  fill: transparent;
  stroke: var(--ink);
  stroke-width: 0.8;
  stroke-linejoin: round;
  opacity: 0;
  transform-box: fill-box;
  transform-origin: center;
  vector-effect: non-scaling-stroke;
}

.part.is-target {
  fill: var(--target-slice);
}

.parts.is-visible .part {
  animation: part-in 560ms cubic-bezier(0.16, 1, 0.3, 1) both;
  animation-delay: calc(var(--index) * 52ms);
}

@keyframes part-in {
  from {
    opacity: 0;
    transform: scale(0.985);
  }

  to {
    opacity: 1;
    transform: scale(1);
  }
}

.user-slice {
  fill: var(--slice);
  opacity: 0;
  transform-box: fill-box;
  transform-origin: center;
  transition:
    opacity 160ms ease,
    transform 460ms cubic-bezier(0.16, 1, 0.3, 1);
}

.user-slice.is-visible {
  opacity: 1;
}

.target-slice {
  fill: none;
  stroke: var(--ink);
  stroke-width: 1.25;
  stroke-dasharray: 3 5;
  stroke-linejoin: round;
  opacity: 0;
  vector-effect: non-scaling-stroke;
  transition: opacity 180ms ease;
}

.target-slice.is-visible {
  opacity: 0.58;
}

.base-line,
.cut-line {
  stroke-linecap: round;
  vector-effect: non-scaling-stroke;
}

.base-line {
  stroke: rgba(36, 35, 31, 0.12);
  stroke-width: 1.35;
}

.cut-line {
  stroke: var(--ink);
  stroke-width: 1.45;
  opacity: 0.82;
  transition: opacity 160ms ease;
}

.base-line.is-locked,
.cut-line.is-locked,
.centre.is-locked {
  opacity: 0.25;
}

.centre {
  fill: var(--ink);
  transition: opacity 160ms ease;
}

.result {
  height: 58px;
  display: grid;
  align-content: center;
  gap: 5px;
}

.result span {
  color: var(--muted);
  font-size: 12px;
  line-height: 1.25;
}

.result strong {
  color: var(--ink);
  font-size: 15px;
  font-weight: 800;
  line-height: 1.25;
}

.next {
  min-width: 82px;
  padding: 10px 18px;
  border: 1px solid var(--ink);
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font: inherit;
  font-size: 13px;
  font-weight: 800;
  cursor: pointer;
  transition: transform 150ms ease, opacity 150ms ease;
}

.next:disabled {
  cursor: default;
  opacity: 0.32;
}

.next:not(:disabled):hover {
  transform: translateY(-1px);
}

.next:not(:disabled):active {
  transform: translateY(1px);
}

.summary {
  position: absolute;
  inset: 0;
  z-index: 12;
  display: grid;
  align-content: center;
  justify-items: center;
  gap: 18px;
  padding: 42px 32px 34px;
  background: var(--paper);
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
  transition: opacity 260ms ease, transform 260ms ease;
}

.summary[hidden] {
  display: none;
}

.summary.is-visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.summary h2 {
  margin: 0;
  font-size: clamp(3.8rem, 16vw, 6.8rem);
  line-height: 0.82;
  letter-spacing: -0.08em;
}

.analysis {
  max-width: 310px;
  min-height: 36px;
  margin: -4px 0 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.4;
}

.stats {
  width: min(100%, 330px);
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.stats div {
  display: grid;
  gap: 4px;
  padding: 13px 12px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
}

.stats span {
  color: var(--muted);
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.stats strong {
  font-size: 14px;
}

.attempts {
  width: min(100%, 340px);
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 10px;
}

.attempt {
  display: grid;
  justify-items: center;
  gap: 5px;
}

.attempt svg {
  width: 44px;
  height: 44px;
  overflow: visible;
}

.attempt circle {
  fill: var(--surface);
  stroke: var(--ink);
  stroke-width: 1;
}

.mini-user {
  fill: var(--slice);
}

.mini-target {
  fill: none;
  stroke: var(--ink);
  stroke-width: 0.9;
  stroke-dasharray: 2 3;
}

.attempt span {
  color: var(--muted);
  font-size: 10px;
  font-weight: 650;
}

.credit {
  position: fixed;
  right: 18px;
  bottom: 16px;
  color: rgba(36, 35, 31, 0.28);
  text-decoration: none;
  font: 11px/1.2 ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
  letter-spacing: 0.08em;
}

.credit:hover {
  color: rgba(36, 35, 31, 0.62);
}

@media (max-width: 520px) {
  .game {
    min-height: 640px;
    gap: 18px;
    padding: 38px 22px 28px;
  }

  .help {
    top: 22px;
    right: 22px;
  }

  .tooltip {
    top: 64px;
    right: 22px;
  }

  .attempts {
    gap: 8px;
  }

  .attempt svg {
    width: 38px;
    height: 38px;
  }
}