:root {
  --bg: #f3f5f8;
  --surface: #ffffff;
  --surface-soft: #f7f9fc;
  --border: #dde3eb;
  --border-strong: #c6d0dc;
  --text: #1f2937;
  --muted: #667085;
  --primary: #2f5d62;
  --primary-soft: #e8f1f1;
  --accent: #6b7280;
  --success: #1f7a4d;
  --success-soft: #edf8f2;
  --danger: #b5473c;
  --danger-soft: #fdf0ef;
  --shadow: 0 8px 22px rgba(15, 23, 42, 0.05);
  --radius: 18px;
  --radius-sm: 14px;
}

* {
  box-sizing: border-box;
}

html {
  font-size: 16px;
}

body {
  margin: 0;
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

[hidden] {
  display: none !important;
}

button,
select,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.page {
  width: min(1260px, calc(100% - 40px));
  margin: 0 auto;
  padding: 18px 0 44px;
}

.topbar {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 18px;
}

.section-kicker {
  margin: 0 0 4px;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.app-title,
.section-title {
  margin: 0;
  line-height: 1.15;
}

.app-title {
  font-size: clamp(1.9rem, 2.8vw, 2.6rem);
  font-weight: 800;
  letter-spacing: -0.03em;
}

.topnav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  padding: 4px;
  background: rgba(255, 255, 255, 0.65);
  border: 1px solid var(--border);
  border-radius: 999px;
}

.home-layout,
.generate-layout,
.quiz-layout,
.results-layout {
  display: grid;
  gap: 20px;
}

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.home-panel,
.generate-panel,
.quiz-header,
.results-card,
.stats-panel,
.attempts-panel {
  padding: 16px;
}

.home-panel {
  background: rgba(255, 255, 255, 0.92);
}

.toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  align-items: center;
  justify-content: space-between;
}

.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
}

.subject-filters {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.chip,
.pill,
.secondary,
.primary,
.select,
.text-button {
  border-radius: 999px;
}

.chip {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  padding: 10px 16px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  transition: background-color 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}

.chip.active {
  background: var(--primary-soft);
  border-color: #d5e3e3;
  color: var(--primary);
  font-weight: 700;
}

.select {
  min-width: 200px;
  min-height: 44px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  padding: 10px 14px;
}

.primary,
.secondary {
  border: 1px solid transparent;
  padding: 12px 18px;
  font-weight: 700;
  transition: background-color 0.15s ease, border-color 0.15s ease, color 0.15s ease, transform 0.15s ease;
}

.primary {
  background: #336b70;
  color: #fff;
}

.primary:hover {
  background: #2c5d61;
  transform: translateY(-1px);
}

.secondary {
  background: #eef2f6;
  color: var(--text);
  border-color: #e2e8f0;
}

.secondary:hover {
  background: #e6ebf1;
}

.text-button {
  border: 0;
  background: transparent;
  color: var(--primary);
  padding: 0;
  font-weight: 700;
}

.quiz-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 300px));
  gap: 18px;
  justify-content: start;
  align-items: stretch;
}

.quiz-card {
  background: var(--surface);
  border: 1px solid #dbe2ea;
  border-radius: 20px;
  padding: 16px;
  box-shadow: var(--shadow);
  display: flex;
  flex-direction: column;
  gap: 14px;
  min-height: 210px;
  transition:
    transform 0.15s ease,
    box-shadow 0.15s ease,
    border-color 0.15s ease;
}

.quiz-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 28px rgba(15, 23, 42, 0.08);
  border-color: var(--border-strong);
}

.quiz-card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  min-height: 32px;
}

.pill {
  display: inline-flex;
  align-items: center;
  padding: 7px 12px;
  min-height: 32px;
  background: #edf5f4;
  color: var(--primary);
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: -0.01em;
}

.muted-pill {
  background: #f3f5f8;
  color: #667085;
}

.quiz-card-title {
  margin: 0;
  font-size: 1.18rem;
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: -0.02em;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  min-height: calc(1.3em * 2);
}

.quiz-card-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: auto;
}

.wide-mobile {
  width: 100%;
}

.quiz-card-actions .primary {
  min-height: 46px;
}

.empty-state {
  padding: 16px;
  border: 1px dashed var(--border-strong);
  border-radius: var(--radius);
  color: var(--muted);
  background: rgba(255, 255, 255, 0.75);
}

.quiz-header {
  display: grid;
  gap: 16px;
}

.quiz-header-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
}

.quiz-header-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 12px;
}

.quiz-title-wrap {
  min-width: 0;
}

.quiz-title {
  margin: 0 0 8px;
  font-size: clamp(1.28rem, 2.2vw, 1.8rem);
  line-height: 1.15;
}

.quiz-info {
  color: var(--muted);
  font-size: 0.92rem;
  font-weight: 600;
}

.quiz-body {
  display: grid;
  gap: 18px;
}

.quiz-form {
  display: grid;
  gap: 18px;
}

.question {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
  display: grid;
  gap: 14px;
}

.question-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px 16px;
}

.question-number {
  display: inline-flex;
  align-items: center;
  padding: 8px 14px;
  min-height: 40px;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary);
  font-weight: 800;
  font-size: 0.88rem;
  line-height: 1;
  white-space: nowrap;
}

.question-type {
  color: var(--muted);
  font-weight: 700;
  font-size: 0.88rem;
  line-height: 1.3;
}

.question-title {
  margin: 0;
  font-size: clamp(1.02rem, 1.7vw, 1.18rem);
  line-height: 1.35;
}

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

.answer-option {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 58px;
  padding: 12px 14px;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: var(--surface);
  transition:
    border-color 0.15s ease,
    background-color 0.15s ease,
    box-shadow 0.15s ease;
  cursor: pointer;
  user-select: none;
}

.answer-option:hover {
  border-color: var(--border-strong);
  background: #fafbfd;
}

.answer-input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.answer-indicator {
  flex: 0 0 auto;
  width: 18px;
  height: 18px;
  border: 2px solid #8591a5;
  background: #fff;
  display: inline-block;
}

.answer-option[data-question-type="single"] .answer-indicator {
  border-radius: 50%;
}

.answer-option[data-question-type="multiple"] .answer-indicator {
  border-radius: 5px;
}

.answer-text {
  font-size: clamp(0.94rem, 1.35vw, 1rem);
  line-height: 1.34;
  font-weight: 600;
  color: var(--text);
}

.answer-option:has(.answer-input:checked) {
  border-color: var(--primary);
  background: var(--primary-soft);
  box-shadow: 0 0 0 3px rgba(47, 93, 98, 0.08);
}

.answer-option:has(.answer-input:checked) .answer-indicator {
  border-color: var(--primary);
  background: var(--primary);
  box-shadow: inset 0 0 0 4px #fff;
}

.sticky-submit {
  position: sticky;
  bottom: 12px;
  z-index: 20;
  display: flex;
  justify-content: center;
  padding-top: 6px;
}

.submit-bar {
  width: min(100%, 760px);
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  border-radius: 999px;
  box-shadow: var(--shadow);
  padding: 10px;
  display: flex;
  justify-content: center;
}

.submit-bar .primary {
  min-width: min(100%, 320px);
}

.section-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 12px;
}

.results-card {
  display: grid;
  gap: 16px;
}

.score-line {
  margin: 0;
  font-size: 1rem;
  font-weight: 800;
}

.results-details {
  display: grid;
  gap: 16px;
}

.result-item {
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  padding: 16px;
  background: var(--surface);
}

.result-ok {
  border-color: #c9e7d6;
  background: var(--success-soft);
}

.result-bad {
  border-color: #f1cbc6;
  background: var(--danger-soft);
}

.result-title-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: center;
  margin-bottom: 10px;
}

.result-title-row h3 {
  margin: 0;
  font-size: 1rem;
}

.result-badge {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.85);
  font-size: 0.9rem;
  font-weight: 800;
}

.result-question {
  font-weight: 700;
}

.muted {
  color: var(--muted);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
}

.stat-card {
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
  background: var(--surface-soft);
}

.stat-label {
  margin: 0 0 8px;
  font-size: 0.9rem;
  color: var(--muted);
  font-weight: 700;
}

.stat-value {
  margin: 0;
  font-size: 1.5rem;
  font-weight: 800;
  line-height: 1.1;
}

.attempts-list {
  display: grid;
  gap: 14px;
}

.attempt-card {
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
  background: var(--surface);
  display: grid;
  gap: 10px;
}

.attempt-top {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: flex-start;
}

.attempt-title {
  margin: 0;
  font-size: 1rem;
  line-height: 1.3;
}

.attempt-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.attempt-line {
  margin: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.attempt-score {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary);
  font-weight: 800;
  white-space: nowrap;
}

.generate-panel {
  padding: 18px;
}

.generate-form {
  display: grid;
  gap: 16px;
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.field {
  display: grid;
  gap: 8px;
}

.field-wide {
  grid-column: 1 / -1;
}

.field-label {
  font-size: 0.92rem;
  font-weight: 700;
  color: var(--text);
}

.input {
  width: 100%;
  min-height: 46px;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: var(--surface);
  color: var(--text);
  padding: 10px 14px;
}

.input:focus,
.select:focus {
  outline: 2px solid rgba(47, 93, 98, 0.18);
  outline-offset: 1px;
  border-color: var(--primary);
}

.generate-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
}

.feedback-success {
  border-style: solid;
  border-color: #c9e7d6;
  background: var(--success-soft);
  color: var(--success);
}

.feedback-error {
  border-style: solid;
  border-color: #f1cbc6;
  background: var(--danger-soft);
  color: var(--danger);
}

.feedback-loading {
  border-style: solid;
  border-color: #dce4ee;
  background: #f7f9fc;
  color: var(--text);
}

@media (max-width: 1100px) {
  .quiz-grid {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  }
}

@media (max-width: 800px) {
  .page {
    width: min(100% - 20px, 1000px);
    padding: 14px 0 28px;
  }

  .topbar {
    align-items: stretch;
  }

  .topnav {
    width: 100%;
    background: transparent;
    border: 0;
    border-radius: 0;
    padding: 0;
    gap: 10px;
  }

  .topnav .chip {
    flex: 1 1 0;
    min-width: 0;
  }

  .quiz-header-top,
  .section-header {
    display: grid;
    grid-template-columns: 1fr;
  }

  .quiz-header-actions {
    justify-content: flex-start;
  }

  .wide-mobile,
  .submit-bar .primary {
    width: 100%;
  }

  .question {
    padding: 16px;
  }

  .answer-option {
    min-height: 60px;
  }

  .form-grid {
    grid-template-columns: 1fr;
  }

  .quiz-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .quiz-card {
    min-height: auto;
  }

  .quiz-card-title {
    min-height: auto;
    -webkit-line-clamp: unset;
  }
}

@media (max-width: 560px) {
  .toolbar {
    align-items: stretch;
  }

  .filter-group {
    width: 100%;
  }

  .subject-filters,
  .select,
  .primary,
  .secondary {
    width: 100%;
  }

  .topnav .chip {
    width: 100%;
    text-align: center;
  }

  .quiz-title {
    font-size: 1.28rem;
  }

  .question-meta {
    flex-direction: column;
    align-items: flex-start;
  }

  .question-title {
    font-size: 1rem;
  }

  .result-title-row,
  .attempt-top,
  .generate-actions {
    flex-direction: column;
    align-items: flex-start;
  }
}