:root {
  --chalkboard: #27624d;
  --chalkboard-dark: #1d4639;
  --chalk: #fff8dc;
  --yellow: #ffd95a;
  --red: #e94f37;
  --blue: #4aa3df;
  --paper: #fff7dc;
  --wood: #b86f32;
  --wood-dark: #875025;
  --drawing-top: 104px;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  font-family: "Nunito", system-ui, sans-serif;
  color: var(--chalk);
  background:
    linear-gradient(90deg, rgba(255, 255, 255, 0.2) 1px, transparent 1px),
    linear-gradient(rgba(255, 255, 255, 0.2) 1px, transparent 1px),
    #f6d870;
  background-size: 44px 44px;
}

.classroom {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  position: relative;
  overflow: hidden;
}

.classroom::before {
  content: "ABC";
  position: absolute;
  top: 24px;
  left: 28px;
  font-family: "Baloo 2", system-ui, sans-serif;
  font-size: clamp(2.2rem, 6vw, 5rem);
  font-weight: 800;
  color: rgba(233, 79, 55, 0.25);
  transform: rotate(-9deg);
}

.classroom::after {
  content: "1 2 3";
  position: absolute;
  right: 24px;
  bottom: 18px;
  font-family: "Baloo 2", system-ui, sans-serif;
  font-size: clamp(2rem, 6vw, 4.8rem);
  font-weight: 800;
  color: rgba(74, 163, 223, 0.28);
  transform: rotate(8deg);
}

.board {
  width: min(1120px, 100%);
  min-height: min(720px, calc(100vh - 48px));
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: clamp(18px, 4vw, 34px);
  padding: clamp(22px, 5vw, 56px);
  border: clamp(12px, 2vw, 22px) solid var(--wood);
  border-bottom-color: var(--wood-dark);
  border-radius: 8px;
  background:
    radial-gradient(circle at 18% 20%, rgba(255, 255, 255, 0.11), transparent 28%),
    linear-gradient(145deg, var(--chalkboard), var(--chalkboard-dark));
  box-shadow: 0 22px 0 var(--wood-dark), 0 28px 42px rgba(61, 37, 15, 0.28);
  position: relative;
  z-index: 1;
}

.drawing-canvas {
  position: absolute;
  inset: var(--drawing-top) 0 0;
  width: 100%;
  height: calc(100% - var(--drawing-top));
  pointer-events: none;
  z-index: 2;
  touch-action: none;
}

.board.drawing-mode .drawing-canvas {
  cursor: crosshair;
  pointer-events: auto;
}

.board > *:not(.drawing-canvas) {
  position: relative;
  z-index: 2;
}

.top-row {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  z-index: 4;
}

.tool-group {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
}

.date-line {
  margin: 0;
  padding: 8px 16px;
  border: 2px dashed rgba(255, 248, 220, 0.75);
  border-radius: 8px;
  font-family: "Baloo 2", system-ui, sans-serif;
  font-size: clamp(1rem, 2.8vw, 1.55rem);
  text-align: center;
  color: var(--yellow);
}

.apple {
  border: 0;
  width: clamp(42px, 8vw, 72px);
  aspect-ratio: 1;
  padding: 0;
  background: var(--red);
  border-radius: 48% 52% 54% 46%;
  position: relative;
  box-shadow: inset -8px -9px 0 rgba(134, 31, 22, 0.25);
  cursor: pointer;
}

.apple::before {
  content: "";
  position: absolute;
  width: 16%;
  height: 34%;
  top: -18%;
  left: 48%;
  border-radius: 999px;
  background: #6b3f1f;
  transform: rotate(18deg);
}

.apple::after {
  content: "";
  position: absolute;
  width: 34%;
  height: 22%;
  top: -8%;
  left: 58%;
  border-radius: 999px 0;
  background: #4f9f57;
  transform: rotate(-22deg);
}

.apple:hover,
.draw-toggle:hover {
  transform: translateY(-2px);
}

.apple:focus-visible,
.draw-toggle:focus-visible {
  outline: 4px solid var(--yellow);
  outline-offset: 4px;
}

.draw-toggle {
  width: clamp(56px, 10vw, 88px);
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  border: 4px solid rgba(255, 248, 220, 0.92);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.1);
  box-shadow: inset 0 0 16px rgba(255, 255, 255, 0.07), 0 6px 0 rgba(0, 0, 0, 0.15);
  cursor: pointer;
}

.draw-toggle[aria-pressed="true"] {
  background: var(--yellow);
  border-color: var(--paper);
}

.mini-chalk {
  width: 72%;
  height: 22%;
  border-radius: 999px;
  background: var(--chalk);
  box-shadow: inset -8px 0 0 rgba(210, 205, 180, 0.75);
  transform: rotate(-22deg);
}

.draw-toggle[aria-pressed="true"] .mini-chalk {
  background: var(--chalkboard-dark);
  box-shadow: inset -8px 0 0 rgba(0, 0, 0, 0.2);
}

.chalk {
  width: clamp(58px, 10vw, 94px);
  height: 16px;
  border-radius: 999px;
  background: var(--chalk);
  box-shadow: 0 4px 0 rgba(0, 0, 0, 0.16);
}

h1 {
  margin: 0;
  font-family: "Baloo 2", system-ui, sans-serif;
  font-size: clamp(3.4rem, 10vw, 8.8rem);
  line-height: 0.9;
  text-align: center;
  text-shadow: 0 4px 0 rgba(0, 0, 0, 0.18);
}

.countdown {
  width: 100%;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: clamp(8px, 1.8vw, 18px);
}

.time-box {
  min-width: 0;
  display: grid;
  place-items: center;
  gap: 4px;
  min-height: clamp(112px, 18vw, 186px);
  padding: clamp(10px, 2vw, 18px) 8px;
  border: 3px solid rgba(255, 248, 220, 0.82);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  box-shadow: inset 0 0 28px rgba(255, 255, 255, 0.05);
}

.time-box span {
  width: 100%;
  display: block;
  font-family: "Baloo 2", system-ui, sans-serif;
  font-size: clamp(2.7rem, 7.8vw, 7.2rem);
  font-weight: 800;
  line-height: 0.9;
  text-align: center;
  color: var(--yellow);
  font-variant-numeric: tabular-nums;
  text-shadow: 0 4px 0 rgba(0, 0, 0, 0.18);
}

.time-box small {
  width: 100%;
  display: block;
  font-size: clamp(0.75rem, 1.7vw, 1.18rem);
  font-weight: 900;
  line-height: 1.05;
  text-align: center;
  text-transform: uppercase;
  overflow-wrap: anywhere;
  color: var(--paper);
}

.message {
  margin: 0;
  font-family: "Baloo 2", system-ui, sans-serif;
  font-size: clamp(1.8rem, 5vw, 4rem);
  line-height: 1;
  text-align: center;
  color: var(--paper);
}

@media (max-width: 760px) {
  :root {
    --drawing-top: 142px;
  }

  body {
    background-size: 34px 34px;
  }

  .classroom {
    min-height: 100svh;
    padding: 14px;
    align-items: stretch;
  }

  .classroom::before {
    top: 8px;
    left: 10px;
    font-size: 3.4rem;
  }

  .classroom::after {
    right: 10px;
    bottom: 6px;
    font-size: 3.1rem;
  }

  .board {
    min-height: calc(100svh - 28px);
    justify-content: flex-start;
    gap: clamp(14px, 3.4svh, 24px);
    padding: 16px;
    border-width: 12px;
    box-shadow: 0 13px 0 var(--wood-dark), 0 18px 28px rgba(61, 37, 15, 0.28);
  }

  .top-row {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 12px;
  }

  .tool-group {
    gap: 12px;
  }

  .apple {
    width: 54px;
  }

  .draw-toggle {
    width: 70px;
  }

  .date-line {
    grid-column: 1 / -1;
    grid-row: 2;
    width: 100%;
    padding: 8px 10px;
    font-size: clamp(1rem, 4.8vw, 1.35rem);
  }

  .chalk {
    width: 72px;
    height: 14px;
  }

  h1 {
    font-size: clamp(3.4rem, 18vw, 5.4rem);
  }

  .countdown {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 10px;
  }

  .time-box {
    min-height: clamp(116px, 28svh, 150px);
    padding: 12px 6px;
    border-width: 2px;
  }

  .time-box span {
    font-size: clamp(3rem, 16vw, 5.2rem);
  }

  .time-box small {
    font-size: clamp(0.78rem, 3.3vw, 1rem);
  }

  .message {
    margin-top: auto;
    padding-bottom: 6px;
    font-size: clamp(1.7rem, 8vw, 2.8rem);
  }
}

@media (max-width: 430px) {
  .classroom {
    padding: 10px;
  }

  .board {
    min-height: calc(100svh - 20px);
    padding: 12px;
    border-width: 10px;
    gap: clamp(12px, 2.8svh, 18px);
  }

  .top-row {
    gap: 10px;
  }

  .apple {
    width: 48px;
  }

  .draw-toggle {
    width: 64px;
    border-width: 3px;
  }

  .chalk {
    width: 58px;
    height: 12px;
  }

  .date-line {
    padding: 7px 8px;
  }

  :root {
    --drawing-top: 128px;
  }

  h1 {
    font-size: clamp(3rem, 17vw, 4.4rem);
  }

  .time-box {
    min-height: clamp(104px, 23svh, 132px);
  }

  .time-box span {
    font-size: clamp(2.55rem, 14vw, 4.2rem);
  }
}

@media (max-width: 350px) {
  .board {
    padding: 10px;
  }

  .apple {
    width: 42px;
  }

  .draw-toggle {
    width: 58px;
  }

  .time-box {
    min-height: 96px;
  }

  .time-box span {
    font-size: 2.45rem;
  }

  .time-box small {
    font-size: 0.72rem;
  }
}