/* ==========================================================================
   1. Theme Variables
   ========================================================================== */

:root {
  color-scheme: light;
  --bg: #f6f7f9;
  --surface: #fff;
  --surface-2: #f0f2f5;
  --surface-3: #e7ebf0;
  --text: #16181d;
  --muted: #667085;
  --border: #d9dee7;
  --border-strong: #bcc5d2;
  --accent: #2563eb;
  --accent-soft: #dbeafe;
  --accent-text: #1d4ed8;
  --success: #15803d;
  --success-soft: #dcfce7;
  --danger: #b42318;
  --danger-soft: #fee4e2;
  --warning: #9a6700;
  --warning-soft: #fff7d6;
  --shadow: 0 8px 28px rgba(16, 24, 40, .07);
  --focus-ring: 0 0 0 3px color-mix(in srgb, var(--accent) 35%, transparent);
}

html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0d1117;
  --surface: #161b22;
  --surface-2: #1f2630;
  --surface-3: #28313d;
  --text: #f4f7fb;
  --muted: #a8b3c2;
  --border: #303a46;
  --border-strong: #445161;
  --accent: #60a5fa;
  --accent-soft: #12243a;
  --accent-text: #93c5fd;
  --success: #4ade80;
  --success-soft: #11301f;
  --danger: #f97066;
  --danger-soft: #3a1717;
  --warning: #facc15;
  --warning-soft: #332b0f;
  --shadow: 0 10px 34px rgba(0, 0, 0, .28);
}

/* ==========================================================================
   2. Reset / Base
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Arial, sans-serif;
  line-height: 1.5;
}

button,
input {
  font: inherit;
}

button {
  -webkit-tap-highlight-color: transparent;
}

button:focus-visible,
input:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* ==========================================================================
   3. Layout
   ========================================================================== */

.shell {
  width: min(1080px, calc(100% - 28px));
  margin: 0 auto;
  padding: 28px 0 44px;
}

.topbar {
  display: flex;
  gap: 16px;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.exam-header {
  display: grid;
  gap: 14px;
  margin-bottom: 14px;
}

/* ==========================================================================
   4. Header
   ========================================================================== */

.eyebrow {
  margin: 0 0 5px;
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--accent-text);
}

h1 {
  margin: 0;
  font-size: clamp(1.45rem, 3vw, 2.15rem);
  line-height: 1.15;
  letter-spacing: -.02em;
}

.subtitle {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: .96rem;
}

.theme-toggle,
.timer-card {
  min-height: 44px;
  padding: 0 13px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  color: var(--text);
  box-shadow: var(--shadow);
  font-weight: 800;
}

.theme-toggle {
  cursor: pointer;
}

.theme-toggle:hover {
  border-color: var(--border-strong);
}

.theme-toggle:focus-visible {
  box-shadow: var(--focus-ring);
}

.nav-link {
  display: inline-flex;
  align-items: center;
  text-decoration: none;
}

.timer-card {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-variant-numeric: tabular-nums;
}

/* ==========================================================================
   5. Buttons
   ========================================================================== */

.btn {
  min-height: 44px;
  padding: 0 15px;
  border-radius: 11px;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  font-weight: 800;
}

.btn:hover:not(:disabled) {
  border-color: var(--border-strong);
}

.btn:focus-visible {
  box-shadow: var(--focus-ring);
}

.btn:disabled {
  opacity: .45;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.btn-success {
  background: var(--success);
  color: #fff;
  border-color: var(--success);
}

.chip {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 9px;
  border-radius: 999px;
  background: var(--surface);
  border: 1px solid var(--border);
  font-size: .78rem;
  font-weight: 800;
  color: var(--muted);
}

/* ==========================================================================
   5b. Certification Landing Page
   Clean, simple, portfolio-inspired
   ========================================================================== */

.landing-body {
  min-height: 100vh;
  background: var(--bg);
}

/* Slightly deeper blue on the landing page to match the portfolio feel. */
.landing-body {
  --accent: #155c93;
  --accent-text: #155c93;
  --accent-soft: #e8f2f9;
}

html[data-theme="dark"] .landing-body {
  --accent: #69b4e7;
  --accent-text: #8bc8ef;
  --accent-soft: #132a3d;
}

.landing-shell {
  min-height: 100vh;
  display: grid;
  align-items: center;
  padding-top: 44px;
  padding-bottom: 44px;
}

.landing-screen {
  display: grid;
  gap: 28px;
  width: 100%;
}

.landing-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
}

.landing-header > div {
  max-width: 760px;
}

.landing-header .eyebrow {
  margin-bottom: 8px;
  text-transform: none;
  letter-spacing: .02em;
  font-size: .82rem;
}

.landing-header h1 {
  max-width: 700px;
  font-size: clamp(2.1rem, 5vw, 3.45rem);
  line-height: 1.04;
  letter-spacing: -.035em;
}

.landing-header .subtitle {
  max-width: 660px;
  margin-top: 10px;
  font-size: 1rem;
  line-height: 1.6;
}

.landing-header .theme-toggle {
  min-height: 40px;
  border-radius: 999px;
  box-shadow: none;
}

.cert-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.cert-card {
  min-height: 330px;
  padding: clamp(24px, 4vw, 32px);
  border: 1px solid var(--border);
  border-radius: 20px;
  background: var(--surface);
  box-shadow: 0 8px 24px rgba(16, 24, 40, .06);
  color: var(--text);
  display: grid;
  grid-template-rows: auto 1fr auto auto;
  gap: 22px;
  text-decoration: none;
}

html[data-theme="dark"] .cert-card {
  box-shadow: 0 10px 28px rgba(0, 0, 0, .22);
}

.cert-card-active {
  border-color: color-mix(in srgb, var(--accent) 38%, var(--border));
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}

.cert-card-active:hover {
  transform: translateY(-3px);
  border-color: var(--accent);
  box-shadow: 0 14px 32px color-mix(in srgb, var(--accent) 10%, transparent);
}

.cert-card-active:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}

.cert-card-disabled {
  background: var(--surface-2);
  color: var(--muted);
  box-shadow: none;
}

.cert-card-topline,
.cert-details {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  flex-wrap: wrap;
}

.cert-code {
  font-size: .95rem;
  font-weight: 900;
  letter-spacing: .07em;
  color: var(--accent-text);
}

.cert-card-disabled .cert-code {
  color: var(--muted);
}

.cert-status {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 0 10px;
  border: 1px solid var(--border);
  border-radius: 999px;
  font-size: .76rem;
  font-weight: 800;
}

.cert-status-ready {
  border-color: color-mix(in srgb, var(--success) 35%, var(--border));
  background: var(--success-soft);
  color: var(--success);
}

.cert-status-building {
  background: var(--surface);
  color: var(--muted);
}

.cert-card-copy h2 {
  margin: 0;
  max-width: 440px;
  font-size: clamp(1.4rem, 3vw, 1.9rem);
  line-height: 1.18;
  letter-spacing: -.025em;
}

.cert-card-copy p {
  margin: 12px 0 0;
  max-width: 540px;
  color: var(--muted);
  line-height: 1.6;
}

.cert-details {
  justify-content: flex-start;
  color: var(--muted);
  font-size: .82rem;
  font-weight: 700;
}

.cert-details span + span::before {
  content: "•";
  margin-right: 10px;
  color: var(--border-strong);
}

.cert-action {
  width: fit-content;
  min-height: 42px;
  padding: 0 15px;
  border-radius: 10px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--accent);
  color: #fff;
  font-weight: 800;
}

.cert-action-disabled {
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--muted);
}

/* ==========================================================================
   6. Start Screen
   ========================================================================== */

.start-screen {
  display: grid;
  gap: 22px;
  margin-top: 28px;
}

.hero-card {
  border: 1px solid var(--border);
  border-radius: 20px;
  background: var(--surface);
  box-shadow: var(--shadow);
  padding: clamp(24px, 5vw, 42px);
}

.hero-card h2 {
  margin: 0;
  font-size: clamp(1.35rem, 3vw, 2rem);
  letter-spacing: -.02em;
}

.hero-card p {
  margin: 10px 0 0;
  color: var(--muted);
  max-width: 720px;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-top: 24px;
}

.mode-card {
  border: 1px solid var(--border);
  border-radius: 18px;
  background: var(--surface-2);
  padding: 20px;
  display: grid;
  gap: 14px;
}

.mode-card h3 {
  margin: 0;
  font-size: 1.1rem;
}

.mode-card p {
  margin: 0;
  color: var(--muted);
  font-size: .92rem;
}

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

.load-error {
  margin-bottom: 16px;
  padding: 16px 18px;
  border: 1px solid var(--danger);
  border-radius: 14px;
  background: var(--danger-soft);
  color: var(--text);
}

.site-disclaimer {
  margin: 18px 2px 0;
  color: var(--muted);
  font-size: .78rem;
  text-align: center;
}

.practice-stats {
  border: 1px solid var(--border);
  border-radius: 16px;
  background: var(--surface);
  box-shadow: var(--shadow);
  padding: 18px 20px;
}

.practice-stats-title {
  margin: 0 0 14px;
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--muted);
}

.practice-stats-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.practice-stat {
  display: grid;
  gap: 2px;
}

.practice-stat-label {
  font-size: .78rem;
  font-weight: 800;
  color: var(--muted);
}

.practice-stat-value {
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.practice-stat-meta {
  font-size: .78rem;
  color: var(--muted);
}

.practice-stat-meta.pass {
  color: var(--success);
}

.practice-stat-meta.fail {
  color: var(--danger);
}

/* ==========================================================================
   6b. Disclaimer Modal
   ========================================================================== */

.modal {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  padding: 20px;
}

.modal-overlay {
  position: absolute;
  inset: 0;
  background: rgba(16, 24, 40, .45);
}

html[data-theme="dark"] .modal-overlay {
  background: rgba(0, 0, 0, .62);
}

.modal-panel {
  position: relative;
  width: min(100%, 480px);
  padding: 24px;
  border: 1px solid var(--border);
  border-radius: 18px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.modal-title {
  margin: 0;
  font-size: 1.25rem;
  letter-spacing: -.02em;
}

.modal-text {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: .94rem;
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 20px;
  flex-wrap: wrap;
}

/* ==========================================================================
   7. Exam Progress
   ========================================================================== */

.progress-row {
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 12px;
  color: var(--muted);
  font-size: .9rem;
}

.progress-track {
  height: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: var(--surface-3);
}

.progress-fill {
  width: 0;
  height: 100%;
  border-radius: inherit;
  background: var(--accent);
  transition: width .2s ease;
}

/* ==========================================================================
   8. Question Navigator
   ========================================================================== */

.navigator {
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--surface);
  box-shadow: var(--shadow);
  padding: 10px 12px;
}

.navigator-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 8px;
  flex-wrap: wrap;
}

.navigator-head-main {
  display: flex;
  align-items: baseline;
  gap: 8px;
  flex-wrap: wrap;
}

.navigator-summary {
  display: none;
  color: var(--muted);
  font-size: .78rem;
  font-weight: 700;
}

.navigator-toggle {
  display: none;
  min-height: 34px;
  padding: 0 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface-2);
  color: var(--text);
  cursor: pointer;
  font-size: .78rem;
  font-weight: 800;
}

.navigator-toggle:hover {
  border-color: var(--border-strong);
}

.navigator-toggle:focus-visible {
  box-shadow: var(--focus-ring);
}

.navigator.navigator-collapsed .question-grid,
.navigator.navigator-collapsed .legend {
  display: none;
}

.navigator-title {
  margin: 0;
  font-size: .85rem;
  font-weight: 800;
}

.legend {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: .72rem;
}

.legend-item {
  display: inline-flex;
  align-items: center;
  gap: 5px;
}

.dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--surface-3);
  border: 1px solid var(--border-strong);
  flex-shrink: 0;
}

.dot.answered {
  background: var(--accent-soft);
  border-color: var(--accent);
}

.dot.current {
  background: var(--accent);
  border-color: var(--accent);
}

.dot.reviewed {
  background: var(--success-soft);
  border-color: var(--success);
}

.question-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 5px;
}

.qnav {
  min-width: 0;
  min-height: 34px;
  padding: 0 2px;
  border: 1px solid var(--border);
  border-radius: 7px;
  background: var(--surface-2);
  color: var(--muted);
  cursor: pointer;
  font-size: .72rem;
  font-weight: 700;
  line-height: 1;
}

.qnav:hover {
  border-color: var(--border-strong);
  color: var(--text);
}

.qnav:focus-visible {
  box-shadow: var(--focus-ring);
}

.qnav.answered {
  border-color: var(--accent);
  background: var(--accent-soft);
  color: var(--accent-text);
  font-weight: 800;
}

.qnav.current {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-weight: 800;
  box-shadow: 0 0 0 1px var(--accent);
}

.qnav.reviewed {
  border-color: var(--success);
  background: var(--success-soft);
  color: var(--success);
  font-weight: 800;
}

.qnav.result-correct {
  border-color: var(--success);
  background: var(--success-soft);
  color: var(--success);
  font-weight: 800;
}

.qnav.result-incorrect {
  border-color: var(--danger);
  background: var(--danger-soft);
  color: var(--danger);
  font-weight: 800;
}

.qnav.result-unanswered {
  border-color: var(--warning);
  background: var(--warning-soft);
  color: var(--warning);
  font-weight: 800;
}

.dot.result-correct {
  background: var(--success-soft);
  border-color: var(--success);
}

.dot.result-incorrect {
  background: var(--danger-soft);
  border-color: var(--danger);
}

.dot.result-unanswered {
  background: var(--warning-soft);
  border-color: var(--warning);
}

.answer-review-status {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 16px;
  padding: 6px 10px;
  border-radius: 999px;
  font-size: .84rem;
  font-weight: 800;
}

.answer-review-status.correct {
  background: var(--success-soft);
  color: var(--success);
  border: 1px solid var(--success);
}

.answer-review-status.incorrect {
  background: var(--danger-soft);
  color: var(--danger);
  border: 1px solid var(--danger);
}

.answer-review-status.unanswered {
  background: var(--warning-soft);
  color: var(--warning);
  border: 1px solid var(--warning);
}

.answer-review-summary {
  margin-top: 18px;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--surface-2);
}

.answer-review-summary p {
  margin: 8px 0 0;
}

.answer-review-summary p:first-child {
  margin-top: 0;
}

/* ==========================================================================
   9. Question Card
   ========================================================================== */

.exam-card {
  border: 1px solid var(--border);
  border-radius: 18px;
  background: var(--surface);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.question-panel {
  padding: clamp(20px, 4vw, 34px);
}

.question-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 18px;
  color: var(--muted);
  font-size: .9rem;
}

.question-count {
  font-weight: 800;
  color: var(--text);
}

.question-type {
  padding: 5px 9px;
  border-radius: 999px;
  background: var(--surface-2);
  border: 1px solid var(--border);
}

.question-text {
  margin: 0 0 22px;
  font-size: clamp(1.15rem, 2.4vw, 1.45rem);
  line-height: 1.4;
  letter-spacing: -.01em;
}

.options-fieldset {
  margin: 0;
  padding: 0;
  border: 0;
  min-width: 0;
}

.exam-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 16px 18px;
  border-top: 1px solid var(--border);
  background: var(--surface-2);
  flex-wrap: wrap;
}

.footer-group {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.helper {
  margin: 14px 2px 0;
  color: var(--muted);
  font-size: .84rem;
}

/* ==========================================================================
   10. Answers
   ========================================================================== */

.options {
  display: grid;
  gap: 11px;
}

.option {
  display: grid;
  grid-template-columns: 22px 28px 1fr;
  gap: 10px;
  align-items: start;
  min-height: 56px;
  padding: 14px 15px;
  border: 1px solid var(--border);
  border-radius: 13px;
  background: var(--surface-2);
  cursor: pointer;
  transition: border-color .15s ease, transform .15s ease, background .15s ease;
}

.option:hover:not(.locked) {
  border-color: var(--border-strong);
  transform: translateY(-1px);
}

.option:has(input:checked) {
  border-color: var(--accent);
  background: var(--accent-soft);
}

.option:has(input:focus-visible) {
  box-shadow: var(--focus-ring);
}

.option input {
  margin-top: 4px;
  accent-color: var(--accent);
}

.option-letter {
  font-weight: 900;
  color: var(--accent-text);
}

.option.correct-option {
  border-color: var(--success);
  background: var(--success-soft);
}

.option.wrong-option {
  border-color: var(--danger);
  background: var(--danger-soft);
}

.option.locked {
  cursor: default;
}

.option.locked:hover {
  transform: none;
}

/* ==========================================================================
   11. Review Feedback
   ========================================================================== */

.review-feedback {
  display: none;
  margin-top: 18px;
  padding: 16px;
  border-radius: 14px;
  border: 1px solid var(--border);
}

.review-feedback.correct {
  display: block;
  border-color: var(--success);
  background: var(--success-soft);
}

.review-feedback.incorrect {
  display: block;
  border-color: var(--danger);
  background: var(--danger-soft);
}

.review-feedback.answer-review-visible {
  display: block;
  border-color: var(--border);
  background: var(--surface-2);
}

.review-feedback h3 {
  margin: 0 0 6px;
  font-size: 1rem;
}

.review-feedback p {
  margin: 6px 0 0;
}

.review-answer {
  font-weight: 800;
}

/* ==========================================================================
   12. Results
   ========================================================================== */

.results {
  display: none;
  margin-top: 18px;
}

.result-summary {
  border: 1px solid var(--border);
  border-radius: 18px;
  background: var(--surface);
  box-shadow: var(--shadow);
  padding: 24px;
}

.result-actions {
  display: grid;
  gap: 12px;
  margin-top: 16px;
}

.result-actions-primary,
.result-actions-secondary {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.result-actions .btn {
  flex: 1 1 auto;
  min-width: min(100%, 180px);
}

.category-performance {
  margin-top: 18px;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--surface-2);
}

.category-performance h3 {
  margin: 0 0 12px;
  font-size: .95rem;
}

.category-performance-note {
  margin: 0 0 12px;
  color: var(--muted);
  font-size: .82rem;
}

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

.category-row {
  display: grid;
  gap: 4px;
}

.category-row-head {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  font-size: .88rem;
  font-weight: 800;
}

.category-row-score {
  color: var(--muted);
  font-weight: 700;
}

.category-row-track {
  height: 6px;
  overflow: hidden;
  border-radius: 999px;
  background: var(--surface-3);
}

.category-row-fill {
  height: 100%;
  border-radius: inherit;
  background: var(--accent);
}

.score {
  margin: 0;
  font-size: clamp(2rem, 5vw, 3.2rem);
  font-weight: 900;
  letter-spacing: -.03em;
  line-height: 1.1;
}

.score.pass {
  color: var(--success);
}

.score.fail {
  color: var(--danger);
}

.result-verdict {
  margin: 6px 0 0;
  font-size: 1.05rem;
  font-weight: 800;
  color: var(--text);
}

.result-verdict.pass {
  color: var(--success);
}

.result-verdict.fail {
  color: var(--danger);
}

.result-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px 20px;
  margin: 18px 0 0;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--surface-2);
}

.result-stat {
  display: grid;
  gap: 2px;
}

.result-stat dt {
  margin: 0;
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .04em;
  text-transform: uppercase;
  color: var(--muted);
}

.result-stat dd {
  margin: 0;
  font-size: 1rem;
  font-weight: 800;
  color: var(--text);
}

.result-summary > p:not(.score):not(.result-verdict) {
  margin: 8px 0 0;
  color: var(--muted);
}

.missed-list {
  display: grid;
  gap: 12px;
  margin-top: 18px;
}

.miss {
  border: 1px solid var(--border);
  border-radius: 15px;
  background: var(--surface);
  padding: 18px;
}

.miss h3 {
  margin: 0 0 12px;
  font-size: 1rem;
}

.answer-label {
  margin-top: 10px;
  font-weight: 800;
}

.answer-label.yours {
  color: var(--danger);
}

.answer-label.correct {
  color: var(--success);
}

.explanation {
  margin-top: 12px;
  color: var(--muted);
}

/* ==========================================================================
   13. Utilities
   ========================================================================== */

.hidden {
  display: none !important;
}

.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;
}

/* ==========================================================================
   14. Responsive Styles
   ========================================================================== */

.footer-actions {
  justify-content: flex-end;
}

@media (min-width: 1200px) {
  .question-grid {
    grid-template-columns: repeat(20, minmax(0, 1fr));
  }
}

@media (min-width: 900px) and (max-width: 1199px) {
  .question-grid {
    grid-template-columns: repeat(16, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  .cert-grid {
    grid-template-columns: 1fr;
  }

  .cert-card {
    min-height: 320px;
  }

  .question-grid {
    grid-template-columns: repeat(8, minmax(0, 1fr));
  }

  .result-stats {
    grid-template-columns: 1fr 1fr;
  }

  .practice-stats-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 620px) {
  .mode-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 560px) {
  .shell {
    width: min(100% - 20px, 1080px);
    padding-top: 18px;
  }

  .landing-shell {
    align-items: start;
  }

  .landing-header .theme-toggle {
    position: absolute;
    top: 16px;
    right: 10px;
  }

  .landing-header {
    padding-top: 56px;
  }

  .cert-card {
    min-height: 0;
    gap: 20px;
  }

  .question-grid {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }

  .navigator-head {
    align-items: flex-start;
    flex-direction: column;
  }

  .navigator-summary {
    display: inline;
  }

  .navigator-toggle {
    display: inline-flex;
    align-items: center;
  }

  .navigator:not(.navigator-collapsed) .navigator-toggle {
    align-self: flex-start;
  }

  .progress-row {
    grid-template-columns: 1fr auto;
  }

  .progress-track {
    grid-column: 1 / -1;
    grid-row: 2;
  }

  .exam-footer {
    align-items: stretch;
  }

  .footer-group {
    width: 100%;
  }

  .footer-group .btn {
    flex: 1;
  }

  .btn-primary,
  .btn-success {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition: none !important;
  }
}