:root {
  --bg: #f4efe7;
  --bg-accent: #e4d3b6;
  --surface: rgba(255, 252, 247, 0.92);
  --surface-strong: #fffaf2;
  --text: #1f2933;
  --muted: #52606d;
  --line: rgba(82, 96, 109, 0.16);
  --primary: #0c6d62;
  --primary-strong: #084c44;
  --accent: #c26a2d;
  --success-bg: #e4f6ea;
  --success-text: #146c2e;
  --error-bg: #fde8e5;
  --error-text: #b33a2b;
  --shadow: 0 24px 60px rgba(28, 36, 44, 0.12);
  --radius-lg: 28px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --font-display: "Avenir Next", "Hiragino Sans", "Noto Sans JP", sans-serif;
  --font-body: "Hiragino Sans", "Noto Sans JP", sans-serif;
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  min-height: 100%;
  font-family: var(--font-body);
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(194, 106, 45, 0.18), transparent 32%),
    linear-gradient(160deg, var(--bg) 0%, #fbf7ef 48%, #f0e7da 100%);
}

body {
  min-height: 100vh;
}

button,
input,
textarea,
select {
  font: inherit;
}

.page {
  width: min(100%, 860px);
  margin: 0 auto;
  padding: 24px 18px 56px;
}

.page.is-practice {
  width: min(100%, 760px);
  padding-top: 18px;
}

.hero {
  padding: 16px 4px 24px;
}

.page.is-practice .hero,
.page.is-practice .landing-card {
  display: none;
}

.eyebrow,
.meta {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.hero h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 3.6rem);
  line-height: 1.02;
}

.lead {
  margin: 14px 0 0;
  max-width: 44rem;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.7;
}

.card {
  background: var(--surface);
  border: 1px solid rgba(255, 255, 255, 0.65);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.landing-card {
  padding: 20px 24px;
}

.practice-card {
  padding: 16px;
}

.practice-panel {
  display: grid;
  gap: 14px;
}

.prompt {
  margin: 0;
  padding: 16px 18px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, rgba(12, 109, 98, 0.09), rgba(228, 211, 182, 0.25));
  font-size: 1rem;
  font-weight: 700;
  line-height: 1.65;
}

.choice-list {
  display: grid;
  gap: 10px;
}

.choice-button {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--surface-strong);
  color: inherit;
  padding: 14px 16px;
  text-align: left;
  display: flex;
  gap: 12px;
  align-items: flex-start;
  min-height: 54px;
  cursor: pointer;
  transition: transform 140ms ease, border-color 140ms ease, box-shadow 140ms ease;
}

.choice-button:hover,
.choice-button:focus-visible {
  border-color: rgba(12, 109, 98, 0.5);
  box-shadow: 0 12px 24px rgba(12, 109, 98, 0.14);
  transform: translateY(-1px);
  outline: none;
}

.choice-button.is-selected {
  border-color: var(--primary);
  background: rgba(12, 109, 98, 0.08);
}

.choice-button.is-disabled {
  cursor: default;
}

.choice-button.is-correct {
  border-color: rgba(20, 108, 46, 0.3);
  background: var(--success-bg);
}

.choice-button.is-wrong {
  border-color: rgba(179, 58, 43, 0.26);
  background: var(--error-bg);
}

.choice-key {
  flex: 0 0 auto;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-weight: 700;
  background: rgba(12, 109, 98, 0.12);
  color: var(--primary-strong);
}

.choice-text {
  line-height: 1.55;
}

.actions,
.feedback-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.button {
  border: none;
  border-radius: 999px;
  min-height: 52px;
  padding: 0 22px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 140ms ease, opacity 140ms ease, box-shadow 140ms ease;
}

.button:hover,
.button:focus-visible {
  transform: translateY(-1px);
  outline: none;
}

.button:disabled {
  cursor: not-allowed;
  opacity: 0.5;
  transform: none;
}

.button-large {
  min-height: 58px;
  padding-inline: 28px;
}

.button-primary {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 16px 30px rgba(12, 109, 98, 0.24);
}

.button-secondary {
  background: rgba(12, 109, 98, 0.09);
  color: var(--primary-strong);
}

.feedback-box,
.message-box {
  border-radius: var(--radius-md);
  padding: 16px;
  display: grid;
  gap: 8px;
}

.feedback-box h3,
.message-box h3 {
  margin: 0;
  font-size: 1rem;
}

.feedback-box p,
.message-box p {
  margin: 0;
  line-height: 1.65;
}

.feedback-box.is-correct {
  background: var(--success-bg);
  color: var(--success-text);
}

.feedback-box.is-wrong,
.message-box.is-error {
  background: var(--error-bg);
  color: var(--error-text);
}

.message-box.is-loading {
  background: rgba(12, 109, 98, 0.08);
  color: var(--primary-strong);
}

.summary-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.4;
}

.summary-row span:last-child {
  text-align: right;
  font-variant-numeric: tabular-nums;
}

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

@media (max-width: 720px) {
  .page {
    padding: 16px 14px 40px;
  }

  .page.is-practice {
    padding-top: 12px;
  }

  .landing-card {
    padding: 16px 18px;
  }

  .practice-card {
    padding: 14px;
    border-radius: 24px;
  }

  .prompt {
    padding: 14px;
    font-size: 0.96rem;
    line-height: 1.55;
  }

  .choice-button {
    min-height: 52px;
    padding: 13px 14px;
  }

  .button {
    width: 100%;
  }

  .actions,
  .feedback-actions {
    flex-direction: column;
  }

  .summary-row {
    font-size: 0.84rem;
    gap: 8px;
  }

  .summary-row span:last-child {
    max-width: 62%;
  }
}