:root {
  color-scheme: light;
  font-family: Inter, ui-rounded, "SF Pro Rounded", system-ui, -apple-system, sans-serif;
  background: #f4f7fb;
  color: #172033;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-width: 0;
  min-height: 100%;
  margin: 0;
  overflow-x: hidden;
}

body {
  background:
    radial-gradient(circle at 8% 4%, rgba(129, 140, 248, 0.18), transparent 34rem),
    radial-gradient(circle at 96% 34%, rgba(45, 212, 191, 0.15), transparent 32rem),
    #f4f7fb;
}

button,
input {
  font: inherit;
}

.term-division-shell {
  width: min(1120px, calc(100% - 2rem));
  min-width: 0;
  margin: 0 auto;
  padding: 1.25rem 0 2rem;
}

.term-division-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.5rem;
  margin: 1rem 0 1.1rem;
}

.eyebrow,
.subtitle,
.local-note,
.state-question,
.structure-label,
.small-expression,
.result-card p,
.division-callout p,
.conclusion-card p {
  margin: 0;
}

.eyebrow {
  color: #5b54a8;
  font-size: 0.84rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h1 {
  max-width: 880px;
  margin: 0.4rem 0 0.35rem;
  font-size: clamp(1.65rem, 3.5vw, 3.15rem);
  line-height: 1.06;
}

.subtitle {
  color: #5b6475;
  font-size: clamp(1rem, 1.7vw, 1.3rem);
  font-weight: 700;
}

.local-note {
  flex: none;
  padding: 0.55rem 0.75rem;
  border: 1px solid rgba(15, 118, 110, 0.22);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.8);
  color: #0f766e;
  font-size: 0.82rem;
  font-weight: 750;
  white-space: nowrap;
}

.term-division-board {
  min-height: 410px;
  display: grid;
  place-items: center;
  padding: clamp(1rem, 3vw, 2rem);
  border: 1px solid rgba(86, 97, 118, 0.17);
  border-radius: 28px;
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 22px 60px rgba(44, 54, 83, 0.12);
  overflow: hidden;
}

.state-panel {
  width: min(100%, 920px);
  min-width: 0;
  text-align: center;
}

.irritation-panel,
.factor-panel {
  display: grid;
  justify-items: center;
  gap: 1.15rem;
}

.hero-expression,
.state-formula,
.result-equation,
.callout-formula {
  font-variant-numeric: tabular-nums;
  font-weight: 850;
  letter-spacing: 0.02em;
}

.hero-expression {
  margin: 0;
  padding: 0.8rem 1.2rem;
  border-radius: 20px;
  background: #eef2ff;
  color: #3730a3;
  font-size: clamp(2rem, 7vw, 4.6rem);
}

.state-question,
.structure-label {
  color: #4d586d;
  font-size: clamp(1rem, 2vw, 1.25rem);
  font-weight: 650;
}

.small-expression {
  color: #596276;
  font-size: 1.05rem;
  font-weight: 750;
}

.factor-chain {
  display: flex;
  align-items: center;
  gap: clamp(0.7rem, 2vw, 1.2rem);
}

.factor-token,
.package-token {
  display: grid;
  min-width: 5.1rem;
  min-height: 5.1rem;
  place-items: center;
  padding: 0.6rem;
  border-radius: 18px;
  font-size: clamp(1.8rem, 5vw, 3rem);
  font-weight: 900;
}

.factor-token {
  background: #ede9fe;
  color: #6d28d9;
}

.package-token {
  border: 2px solid #0f766e;
  background: #ccfbf1;
  color: #115e59;
}

.operator {
  color: #64748b;
  font-size: 2rem;
  font-weight: 900;
}

.state-formula {
  margin: 0;
  color: #303a51;
  font-size: clamp(1.45rem, 3vw, 2.2rem);
}

.package-panel {
  display: grid;
  gap: 0.9rem;
}

.package-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 8.5rem), 1fr));
  gap: clamp(0.55rem, 1.4vw, 0.9rem);
  width: 100%;
}

.division-package {
  --package-progress: 1;
  position: relative;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.35rem;
  min-width: 0;
  padding: 1.15rem 0.65rem 0.7rem;
  border: 2px solid #5eead4;
  border-radius: 17px;
  background: #f0fdfa;
  opacity: calc(0.18 + var(--package-progress) * 0.82);
  transform: translateY(calc((1 - var(--package-progress)) * 16px)) scale(calc(0.94 + var(--package-progress) * 0.06));
  transition: border-color 180ms ease, background 180ms ease, opacity 180ms ease;
}

.division-package.is-chosen {
  border-color: #4f46e5;
  background: #eef2ff;
  box-shadow: 0 8px 24px rgba(79, 70, 229, 0.17);
}

.division-package.is-muted {
  opacity: 0.34;
}

.package-number {
  position: absolute;
  top: 0.25rem;
  left: 0.55rem;
  color: #64748b;
  font-size: 0.7rem;
  font-weight: 850;
}

.x-unit {
  display: grid;
  min-width: 0;
  min-height: 2.25rem;
  place-items: center;
  border-radius: 9px;
  background: #0f766e;
  color: #fff;
  font-weight: 900;
}

.division-callout,
.result-card,
.conclusion-card,
.explore-panel {
  width: min(100%, 720px);
  margin: 0 auto;
  border-radius: 18px;
}

.division-callout {
  display: grid;
  gap: 0.35rem;
  padding: 0.8rem 1rem;
  background: #fff7ed;
  color: #9a3412;
}

.callout-formula {
  font-size: clamp(1.2rem, 2.5vw, 1.75rem);
}

.result-card {
  padding: 0.85rem 1rem;
  background: #ecfdf5;
  color: #065f46;
}

.result-equation {
  margin: 0.15rem 0 0;
  font-size: clamp(1.35rem, 3vw, 2rem);
}

.range-control {
  display: grid;
  gap: 0.45rem;
  padding: 0.75rem 1rem;
  border-radius: 16px;
  background: #f8fafc;
  color: #334155;
  font-weight: 720;
}

.range-control input {
  width: 100%;
  min-height: 44px;
  accent-color: #4f46e5;
}

.range-scale {
  display: flex;
  justify-content: space-between;
  color: #64748b;
  font-size: 0.78rem;
}

.conclusion-card {
  padding: 0.9rem 1rem;
  background: #ede9fe;
  color: #4c1d95;
}

.conclusion-card h2 {
  margin: 0 0 0.25rem;
  font-size: clamp(1.15rem, 2.4vw, 1.65rem);
}

.term-division-insight {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 1rem;
  margin-top: 1rem;
  padding: 0.85rem 1rem;
  border: 1px solid rgba(86, 97, 118, 0.16);
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.88);
}

.insight-text {
  margin: 0;
  color: #334155;
  font-weight: 760;
}

.term-division-controls {
  display: flex;
  gap: 0.6rem;
}

.primary-button,
.reset-button {
  min-height: 48px;
  padding: 0.7rem 1rem;
  border: 0;
  border-radius: 14px;
  cursor: pointer;
  font-weight: 820;
}

.primary-button {
  background: #4f46e5;
  color: #fff;
}

.reset-button {
  background: #e2e8f0;
  color: #334155;
}

.primary-button:disabled {
  cursor: wait;
  opacity: 0.48;
}

button:focus-visible,
input:focus-visible,
a:focus-visible {
  outline: 4px solid rgba(79, 70, 229, 0.28);
  outline-offset: 3px;
}

[hidden] {
  display: none !important;
}

.visually-hidden {
  position: absolute !important;
  width: 1px !important;
  height: 1px !important;
  padding: 0 !important;
  margin: -1px !important;
  overflow: hidden !important;
  clip: rect(0, 0, 0, 0) !important;
  white-space: nowrap !important;
  border: 0 !important;
}

@media (max-width: 640px) {
  .term-division-shell {
    width: min(100% - 1rem, 1120px);
    padding-top: 0.7rem;
  }

  .term-division-header {
    display: grid;
    gap: 0.7rem;
  }

  .local-note {
    justify-self: start;
  }

  .term-division-board {
    min-height: 430px;
    border-radius: 20px;
  }

  .term-division-insight {
    grid-template-columns: 1fr;
  }

  .term-division-controls {
    width: 100%;
  }

  .term-division-controls button {
    flex: 1;
  }
}

@media (max-width: 360px) {
  .term-division-board {
    min-height: 455px;
    padding: 0.75rem;
  }

  .package-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .division-package {
    padding-inline: 0.45rem;
  }

  .term-division-controls {
    display: grid;
  }
}

@media (orientation: landscape) and (max-height: 820px) {
  .term-division-shell {
    padding-top: 0.55rem;
  }

  .term-division-header {
    margin-block: 0.55rem 0.7rem;
  }

  .term-division-board {
    min-height: 310px;
    padding: 0.8rem 1rem;
  }

  .division-package {
    padding-block: 1rem 0.55rem;
  }
}

@media (min-width: 1500px) {
  .term-division-shell {
    width: min(1280px, calc(100% - 4rem));
  }

  .term-division-board {
    min-height: 500px;
  }

  .package-grid {
    gap: 1.15rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
  }
}