:root {
  --bg: #f7fafc;
  --surface: #ffffff;
  --text: #12263a;
  --muted: #5c6b7a;
  --primary: #0f766e;
  --primary-strong: #0b5f59;
  --accent: #f59e0b;
  --good: #15803d;
  --bad: #b91c1c;
  --ring: rgba(15, 118, 110, 0.25);
  --border: #d9e3ec;
  --shadow: 0 20px 45px rgba(18, 38, 58, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Plus Jakarta Sans", system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: radial-gradient(circle at 12% 15%, #d6f2ee 0%, transparent 28%),
    radial-gradient(circle at 88% 10%, #fef0d2 0%, transparent 28%),
    linear-gradient(160deg, #eef4f8 0%, var(--bg) 45%, #e9f3f2 100%);
  display: grid;
  place-items: center;
  padding: 1rem;
}

.bg-shape {
  position: fixed;
  border-radius: 999px;
  opacity: 0.38;
  filter: blur(2px);
  z-index: -1;
}

.bg-shape-one {
  width: min(48vw, 420px);
  height: min(48vw, 420px);
  background: #a0e7dc;
  top: -110px;
  left: -120px;
}

.bg-shape-two {
  width: min(42vw, 350px);
  height: min(42vw, 350px);
  background: #fbd38d;
  bottom: -120px;
  right: -80px;
}

.app-shell {
  width: min(760px, 100%);
}

.top-nav {
  display: flex;
  gap: 0.55rem;
  margin-bottom: 0.9rem;
}

.top-nav a {
  text-decoration: none;
  color: var(--text);
  font-weight: 700;
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.45rem 0.8rem;
}

.top-nav a[aria-current="page"] {
  background: #dff4f1;
  border-color: #b9e7e0;
}

.card {
  background: color-mix(in srgb, var(--surface) 92%, #ffffff 8%);
  border: 1px solid var(--border);
  border-radius: 22px;
  padding: clamp(1rem, 3vw, 2rem);
  box-shadow: var(--shadow);
  animation: fade-up 280ms ease;
}

.hidden {
  display: none;
}

.hub-card {
  text-align: center;
}

.hub-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 0.75rem;
  margin-top: 1.2rem;
}

.hub-link {
  display: block;
  text-align: left;
  text-decoration: none;
  color: inherit;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 1rem;
  background: #fff;
  transition: transform 180ms ease, box-shadow 180ms ease, border-color 180ms ease;
}

.hub-link:hover {
  transform: translateY(-2px);
  border-color: #b7d6dd;
  box-shadow: 0 14px 28px rgba(18, 38, 58, 0.1);
}

.hub-link h2 {
  margin: 0;
  font-size: 1.15rem;
}

.hub-link p {
  margin: 0.45rem 0 0;
  color: var(--muted);
}

.eyebrow {
  margin: 0;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--primary);
}

h1,
h2 {
  margin: 0.3rem 0 0;
}

.subtitle {
  margin: 0.6rem 0 0;
  color: var(--muted);
}

.setup-form {
  margin-top: 1.2rem;
  display: grid;
  gap: 1rem;
}

fieldset {
  margin: 0;
  border: 0;
  padding: 0;
}

legend {
  font-weight: 700;
  margin-bottom: 0.6rem;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 0.55rem;
}

.fact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 0.55rem;
}

.range-inputs {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 0.65rem;
}

.range-inputs .question-count {
  justify-content: space-between;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.7rem 0.75rem;
  background: #fff;
}

.range-inputs .question-count label {
  font-weight: 700;
}

.range-hint {
  margin: 0.55rem 0 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.set-input-row {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.7rem 0.75rem;
  background: #fff;
}

.toggle-row {
  justify-content: flex-start;
  gap: 0.6rem;
}

.toggle-row input[type="checkbox"] {
  width: 1.05rem;
  height: 1.05rem;
  margin: 0;
  min-width: 0;
  accent-color: var(--primary);
}

.chip {
  position: relative;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.72rem 0.8rem;
  font-weight: 600;
  background: #fff;
  transition: border-color 180ms ease, box-shadow 180ms ease, transform 180ms ease;
  cursor: pointer;
}

.chip:hover {
  transform: translateY(-1px);
}

.chip input {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
}

.chip:has(input:checked) {
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--ring);
}

.question-count {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.65rem;
}

.question-count input[type="number"],
.answer-form input {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.65rem 0.75rem;
  font: inherit;
  min-width: 115px;
}

.question-count input[type="number"]:focus,
.answer-form input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--ring);
}

.error-text {
  margin: 0;
  min-height: 1.25rem;
  color: var(--bad);
  font-weight: 600;
}

.btn {
  appearance: none;
  border: 0;
  border-radius: 12px;
  font: inherit;
  font-weight: 700;
  padding: 0.72rem 1rem;
  cursor: pointer;
}

.btn-primary {
  color: #fff;
  background: linear-gradient(135deg, var(--primary), #14a098);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-strong), var(--primary));
}

.btn-ghost {
  background: #edf4f6;
  color: var(--text);
}

.practice-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.progress-wrap {
  flex: 1;
  max-width: 500px;
}

.progress-wrap p {
  margin: 0;
  text-align: right;
  font-weight: 600;
  color: var(--muted);
}

.progress-track {
  margin-top: 0.45rem;
  width: 100%;
  height: 10px;
  background: #e3ebf1;
  border-radius: 999px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--accent), var(--primary));
  transition: width 200ms ease;
}

.problem-wrap {
  margin-top: 2rem;
  display: grid;
  gap: 1rem;
  justify-items: center;
}

.problem {
  margin: 0;
  font-size: clamp(2rem, 8vw, 3rem);
  font-weight: 800;
}

.answer-form {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.7rem;
}

.answer-form input {
  min-width: 160px;
}

.feedback {
  min-height: 1.3rem;
  margin: 0;
  font-weight: 700;
}

.feedback.good {
  color: var(--good);
}

.feedback.bad {
  color: var(--bad);
}

.results-text {
  margin: 0.75rem 0 0;
  color: var(--muted);
  font-size: 1.05rem;
}

.results-actions {
  margin-top: 1.25rem;
}

.typing-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 0.7rem;
}

.typing-stat-box {
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #fff;
  padding: 0.75rem;
}

.typing-stat-box p {
  margin: 0;
  color: var(--muted);
  font-weight: 600;
}

.typing-stat-box strong {
  display: block;
  margin-top: 0.25rem;
  font-size: 1.2rem;
}

.typing-text-wrap {
  margin-top: 1rem;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1rem;
  background: #fff;
}

.target-text {
  margin: 0;
  line-height: 1.65;
  font-size: 1.04rem;
}

.typing-form {
  margin-top: 1rem;
  display: grid;
  gap: 0.65rem;
}

.typing-form label {
  font-weight: 700;
}

.typing-form textarea {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.8rem;
  font: inherit;
  resize: vertical;
}

.typing-form textarea:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 4px var(--ring);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  border: 0;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
}

@media (max-width: 640px) {
  .top-nav {
    flex-wrap: wrap;
  }

  .practice-top {
    flex-direction: column;
    align-items: stretch;
  }

  .progress-wrap p {
    text-align: left;
  }

  .answer-form input,
  .answer-form button {
    width: 100%;
  }
}

@keyframes fade-up {
  from {
    transform: translateY(8px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}