:root {
  color-scheme: light;

  --bg-a: #dff3ef;
  --bg-b: #e8ecff;
  --bg-c: #fff7ea;

  --text: #10202b;
  --muted: #52646f;

  --glass-bg: rgba(255, 255, 255, 0.38);
  --glass-bg-strong: rgba(255, 255, 255, 0.56);
  --glass-border: rgba(255, 255, 255, 0.72);
  --line: rgba(20, 32, 43, 0.13);

  --brand: #1f7a4a;
  --brand-2: #145a38;
  --brand-glow: rgba(31, 122, 74, 0.24);

  --blue-glow: rgba(66, 153, 225, 0.23);
  --orange-glow: rgba(255, 180, 82, 0.22);

  --good-bg: rgba(226, 248, 234, 0.72);
  --good-text: #134923;

  --warn-bg: rgba(255, 242, 194, 0.72);
  --warn-text: #614600;

  --danger-bg: rgba(255, 220, 220, 0.72);
  --danger-text: #7a1d1d;

  --focus: #ffbf47;
  --shadow: 0 28px 80px rgba(16, 32, 43, 0.18);
  --shadow-soft: 0 18px 50px rgba(16, 32, 43, 0.12);
  --radius-xl: 30px;
  --radius-lg: 22px;
  --radius-md: 16px;
}

html[data-theme="dark"] {
  color-scheme: dark;

  --bg-a: #071014;
  --bg-b: #111d2b;
  --bg-c: #142018;

  --text: #f4fbff;
  --muted: #bdcbd4;

  --glass-bg: rgba(18, 29, 38, 0.46);
  --glass-bg-strong: rgba(18, 29, 38, 0.68);
  --glass-border: rgba(255, 255, 255, 0.15);
  --line: rgba(255, 255, 255, 0.14);

  --brand: #8ce2ad;
  --brand-2: #b0f0c4;
  --brand-glow: rgba(140, 226, 173, 0.20);

  --blue-glow: rgba(92, 175, 255, 0.18);
  --orange-glow: rgba(255, 180, 82, 0.13);

  --good-bg: rgba(20, 65, 36, 0.68);
  --good-text: #b7f5c7;

  --warn-bg: rgba(82, 62, 18, 0.68);
  --warn-text: #ffe49b;

  --danger-bg: rgba(75, 28, 28, 0.70);
  --danger-text: #ffc0c0;

  --focus: #ffd166;
  --shadow: 0 30px 90px rgba(0, 0, 0, 0.46);
  --shadow-soft: 0 20px 60px rgba(0, 0, 0, 0.34);
}

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
}

body {
  min-height: 100%;
  margin: 0;
  color: var(--text);
  font-family: Arial, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
  background:
    radial-gradient(circle at 8% 8%, var(--brand-glow), transparent 24rem),
    radial-gradient(circle at 88% 12%, var(--blue-glow), transparent 26rem),
    radial-gradient(circle at 50% 98%, var(--orange-glow), transparent 30rem),
    linear-gradient(135deg, var(--bg-a), var(--bg-b) 48%, var(--bg-c));
  background-attachment: fixed;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255,255,255,0.18) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.14) 1px, transparent 1px);
  background-size: 42px 42px;
  mask-image: linear-gradient(to bottom, rgba(0,0,0,0.55), transparent 74%);
}

a {
  color: var(--brand);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.16em;
}

a:hover {
  color: var(--brand-2);
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--glass-bg-strong);
  color: var(--text);
  padding: 0.75rem 1rem;
  z-index: 1000;
}

.skip-link:focus {
  left: 0;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  padding: 1rem 1rem 0;
}

.header-inner,
.page-title,
.card,
.container,
.footer-inner,
.dropdown-content {
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft);
  backdrop-filter: blur(24px) saturate(155%);
  -webkit-backdrop-filter: blur(24px) saturate(155%);
}

.header-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0.8rem 0.95rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  justify-content: space-between;
  border-radius: var(--radius-xl);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--text);
  text-decoration: none;
  font-weight: 800;
}

.logo-img {
  width: 58px;
  height: 58px;
  object-fit: contain;
  filter: drop-shadow(0 8px 20px rgba(0,0,0,0.18));
}

.brand-text {
  font-size: 1.42rem;
  letter-spacing: -0.03em;
}

.nav {
  display: flex;
  gap: 0.45rem;
  align-items: center;
  flex-wrap: wrap;
}

.nav a,
.nav button,
.theme-toggle {
  min-height: 42px;
}

.nav a,
.dropbtn,
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.54rem 0.78rem;
  color: var(--text);
  background: rgba(255,255,255,0.20);
  border: 1px solid var(--glass-border);
  border-radius: 999px;
  font: inherit;
  font-weight: 800;
  text-decoration: none;
  cursor: pointer;
}

html[data-theme="dark"] .nav a,
html[data-theme="dark"] .dropbtn,
html[data-theme="dark"] .theme-toggle {
  background: rgba(255,255,255,0.06);
}

.nav a:hover,
.nav a:focus-visible,
.dropbtn:hover,
.dropbtn:focus-visible,
.theme-toggle:hover,
.theme-toggle:focus-visible {
  background: var(--brand-glow);
  border-color: var(--brand);
}

.dropdown {
  position: relative;
}

.dropdown-content {
  display: none;
  position: absolute;
  right: 0;
  top: calc(100% + 0.55rem);
  min-width: 285px;
  padding: 0.55rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
}

.dropdown:hover .dropdown-content,
.dropdown:focus-within .dropdown-content {
  display: grid;
  gap: 0.3rem;
}

.dropdown-content a {
  border-radius: var(--radius-md);
  justify-content: flex-start;
  width: 100%;
}

main {
  max-width: 1120px;
  margin: 0 auto;
  padding: 1.6rem 1rem 3.7rem;
}

.page-title {
  text-align: center;
  margin: 1rem auto 1.25rem;
  padding: clamp(1.3rem, 3vw, 2.2rem);
  max-width: 920px;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
}

.page-title img {
  max-width: 174px;
  height: auto;
  display: block;
  margin: 0 auto 0.75rem;
  filter: drop-shadow(0 10px 24px rgba(0,0,0,0.16));
}

.page-title h1 {
  margin: 0;
  font-size: clamp(1.9rem, 4vw, 3.15rem);
  line-height: 1.08;
  letter-spacing: -0.055em;
}

.page-title p {
  margin: 0.7rem auto 0;
  max-width: 760px;
  color: var(--muted);
  font-size: 1.05rem;
}

.grid {
  display: grid;
  gap: 1rem;
}

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

.card,
.container {
  border-radius: var(--radius-xl);
  padding: 1.35rem;
}

.tool-form {
  margin-top: 1rem;
}

label {
  display: block;
  font-weight: 800;
  margin-bottom: 0.35rem;
}

.help {
  color: var(--muted);
  font-size: 0.92rem;
  margin-top: 0.3rem;
}

input[type="text"],
input[type="number"] {
  width: 100%;
  min-height: 50px;
  padding: 0.82rem 0.95rem;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  background: rgba(255,255,255,0.44);
  color: var(--text);
  font-size: 16px;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.35),
    0 8px 24px rgba(16,32,43,0.07);
}

html[data-theme="dark"] input[type="text"],
html[data-theme="dark"] input[type="number"] {
  background: rgba(7, 14, 20, 0.42);
}

input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

input[type="number"] {
  -moz-appearance: textfield;
  appearance: textfield;
}

input:focus,
button:focus-visible,
a:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

.button,
button.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 1px solid rgba(255,255,255,0.24);
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--brand), var(--brand-2));
  color: #fff;
  padding: 0.78rem 1.05rem;
  font-size: 16px;
  font-weight: 800;
  cursor: pointer;
  text-decoration: none;
  box-shadow: 0 12px 30px rgba(20, 95, 58, 0.24);
}

.button:hover,
button.button:hover {
  color: #fff;
  transform: translateY(-1px);
}

.button-secondary {
  background: var(--glass-bg-strong);
  color: var(--text);
  border-color: var(--glass-border);
  box-shadow: none;
}

.button-secondary:hover {
  color: var(--text);
}

.form-actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1rem;
}

.alert {
  padding: 0.95rem 1rem;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  margin: 1rem 0;
}

.alert-good { background: var(--good-bg); color: var(--good-text); }
.alert-warn { background: var(--warn-bg); color: var(--warn-text); }
.alert-danger { background: var(--danger-bg); color: var(--danger-text); }

.results-table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
  overflow: hidden;
  border-radius: var(--radius-lg);
  background: rgba(255,255,255,0.32);
}

html[data-theme="dark"] .results-table {
  background: rgba(7,14,20,0.30);
}

.results-table th,
.results-table td {
  border-bottom: 1px solid var(--line);
  padding: 0.82rem;
  text-align: left;
  vertical-align: top;
}

.results-table th {
  color: var(--muted);
  font-size: 0.9rem;
}

.results-table tr:last-child td {
  border-bottom: 0;
}

.result-number {
  font-variant-numeric: tabular-nums;
  font-weight: 800;
}

.kpi {
  display: grid;
  gap: 0.3rem;
  padding: 1rem;
  background: rgba(255,255,255,0.34);
  border: 1px solid var(--glass-border);
  border-left: 5px solid var(--brand);
  border-radius: var(--radius-lg);
}

html[data-theme="dark"] .kpi {
  background: rgba(7,14,20,0.32);
}

.kpi strong {
  font-size: 1.35rem;
}

.converter-box {
  max-width: 540px;
  margin: 0 auto;
  text-align: center;
}

.converter-box input {
  max-width: 190px;
  text-align: center;
}

.converter-result {
  min-height: 34px;
  margin-top: 1rem;
  font-size: 1.18rem;
  font-weight: 800;
}

.disclaimer {
  font-size: 0.92rem;
  color: var(--muted);
}

.footer {
  color: var(--muted);
  padding: 1.4rem 1rem;
  text-align: center;
}

.footer-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 1rem;
  border-radius: var(--radius-xl);
}

@media (max-width: 780px) {
  .header-inner {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .nav {
    justify-content: center;
  }

  .dropdown-content {
    left: 50%;
    right: auto;
    transform: translateX(-50%);
  }

  .grid-2 {
    grid-template-columns: 1fr;
  }

  .results-table {
    display: block;
    overflow-x: auto;
  }
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .header-inner,
  .page-title,
  .card,
  .container,
  .footer-inner,
  .dropdown-content {
    background: var(--glass-bg-strong);
  }
}



/* V1.6 logo/header refinements */
.brand-text-only {
  font-size: 1.55rem;
  letter-spacing: -0.045em;
  color: var(--text);
}

.theme-logo-light,
.theme-logo-dark {
  max-width: 174px;
  height: auto;
  display: block;
  margin: 0 auto 0.75rem;
  filter: drop-shadow(0 10px 24px rgba(0,0,0,0.16));
}

.theme-logo-dark {
  display: none;
}

html[data-theme="dark"] .theme-logo-light {
  display: none;
}

html[data-theme="dark"] .theme-logo-dark {
  display: block;
}


/* V1.7 fixes */
.tools-link {
  display: inline-flex;
}

.dropdown {
  position: relative;
  padding-bottom: 0.4rem;
  margin-bottom: -0.4rem;
}

.dropdown-content {
  top: calc(100% - 0.05rem);
}

.dropdown::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 100%;
  height: 0.65rem;
}

.theme-logo {
  max-width: 174px;
  height: auto;
  display: block;
  margin: 0 auto 0.75rem;
  filter: drop-shadow(0 10px 24px rgba(0,0,0,0.16));
}

.theme-logo-dark {
  display: none;
}

html[data-theme="dark"] .theme-logo-light {
  display: none !important;
}

html[data-theme="dark"] .theme-logo-dark {
  display: block !important;
}

.converter-grid {
  margin-top: 1rem;
  align-items: start;
}

.converter-clear {
  justify-content: center;
  margin-top: 1.4rem;
}

.reference-note {
  margin-top: 1.4rem;
}

.converter-box {
  max-width: 860px;
}

.converter-box input {
  max-width: 220px;
}


/* V1.8 strict logo theme fix */
.page-title .theme-logo {
  max-width: 174px;
  height: auto;
  margin: 0 auto 0.75rem;
  filter: drop-shadow(0 10px 24px rgba(0,0,0,0.16));
}

html[data-theme="light"] .page-title .theme-logo-light,
html:not([data-theme="dark"]) .page-title .theme-logo-light {
  display: block !important;
}

html[data-theme="light"] .page-title .theme-logo-dark,
html:not([data-theme="dark"]) .page-title .theme-logo-dark {
  display: none !important;
}

html[data-theme="dark"] .page-title .theme-logo-light {
  display: none !important;
}

html[data-theme="dark"] .page-title .theme-logo-dark {
  display: block !important;
}


/* V1.9 strict logo text-only dark-mode swap */
.page-title .theme-logo {
  max-width: 174px;
  height: auto;
  margin: 0 auto 0.75rem;
  filter: drop-shadow(0 10px 24px rgba(0,0,0,0.16));
}

.page-title .theme-logo-light {
  display: block !important;
}

.page-title .theme-logo-dark {
  display: none !important;
}

html[data-theme="dark"] .page-title .theme-logo-light {
  display: none !important;
}

html[data-theme="dark"] .page-title .theme-logo-dark {
  display: block !important;
}


/* V2.0 converter/tool additions */
.grid-2 .card h2 {
  margin-top: 0;
}

.converter-box .grid-2 {
  width: 100%;
}


/* V2.1 pressure dropdown converter */
select {
  width: 100%;
  min-height: 50px;
  padding: 0.82rem 0.95rem;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  background: rgba(255,255,255,0.44);
  color: var(--text);
  font-size: 16px;
  font-weight: 700;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.35),
    0 8px 24px rgba(16,32,43,0.07);
}

html[data-theme="dark"] select {
  background: rgba(7, 14, 20, 0.42);
}

.converter-row {
  display: grid;
  grid-template-columns: minmax(180px, 1.2fr) minmax(130px, 0.8fr) minmax(130px, 0.8fr);
  gap: 1rem;
  align-items: end;
  margin-top: 1rem;
}

.pressure-converter-box {
  max-width: 760px;
}

@media (max-width: 780px) {
  .converter-row {
    grid-template-columns: 1fr;
  }
}


/* V2.2 improved dropdown/select styling */
select {
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;

  width: 100%;
  min-height: 56px;
  padding: 0.9rem 3rem 0.9rem 1rem;

  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);

  color: var(--text);
  background:
    linear-gradient(135deg, rgba(255,255,255,0.64), rgba(255,255,255,0.36)),
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='18' height='18' viewBox='0 0 20 20'%3E%3Cpath fill='%2310202b' d='M5.5 7.5l4.5 5 4.5-5z'/%3E%3C/svg%3E") no-repeat right 1rem center;

  font-size: 1.05rem;
  font-weight: 800;
  letter-spacing: 0.01em;

  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.50),
    0 10px 26px rgba(16,32,43,0.10);

  cursor: pointer;
}

html[data-theme="dark"] select {
  color: var(--text);
  background:
    linear-gradient(135deg, rgba(20,32,42,0.82), rgba(20,32,42,0.48)),
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='18' height='18' viewBox='0 0 20 20'%3E%3Cpath fill='%23f4fbff' d='M5.5 7.5l4.5 5 4.5-5z'/%3E%3C/svg%3E") no-repeat right 1rem center;
}

select:hover {
  border-color: var(--brand);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.50),
    0 12px 30px rgba(16,32,43,0.14);
}

select:focus {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

select option {
  color: #10202b;
  background: #ffffff;
  font-weight: 700;
}

html[data-theme="dark"] select option {
  color: #f4fbff;
  background: #17212b;
}

.converter-row {
  grid-template-columns: minmax(220px, 1.25fr) minmax(165px, 0.8fr) minmax(165px, 0.8fr);
  gap: 1.1rem;
}

.pressure-converter-box {
  max-width: 860px;
}

@media (max-width: 780px) {
  .converter-row {
    grid-template-columns: 1fr;
  }
}


/* V2.4 tire wear calculator */
.wear-calculator-box {
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.wear-row {
  margin-top: 1rem;
}

.wear-mileage-group {
  margin-top: 1rem;
}

.wear-results {
  margin-top: 1.4rem;
}

.wear-results .kpi {
  min-height: 112px;
}

.wear-results .kpi span {
  color: var(--muted);
  font-weight: 800;
}

.wear-results .kpi strong {
  font-size: clamp(1.15rem, 2.2vw, 1.65rem);
}


/* V2.5 wear bar threshold wording */
#wearBarHelp {
  margin-bottom: 0;
}


/* V2.6 tire wear calculator alignment/default-state fixes */
.wear-bar-threshold-field {
  align-self: start;
}

.wear-bar-threshold-field input {
  margin-top: 0;
}

.wear-bar-threshold-field .help {
  min-height: 1.35rem;
}

.wear-mileage-group[hidden],
#odometerMileageGroup[hidden],
#totalMileageGroup[hidden] {
  display: none !important;
}


/* V2.7 wear bar alignment fix */
.wear-row {
  align-items: end;
}

.wear-bar-threshold-field {
  align-self: end;
}

.wear-bar-reference-note {
  margin-top: 0.55rem;
  margin-bottom: 0;
  text-align: center;
}

.wear-bar-threshold-field input {
  margin-top: 0;
}


/* V2.8 hard-coded wear bar and wear percentage color coding */
.wear-row-two {
  grid-template-columns: minmax(220px, 1fr) minmax(220px, 1fr);
  max-width: 620px;
}

.wear-bar-reference-note {
  margin-top: 0.6rem;
  margin-bottom: 0;
  text-align: left;
  font-weight: 800;
}

.wear-score-box {
  transition: background 0.2s ease, color 0.2s ease;
}

.wear-score-box.wear-green {
  background: rgba(31, 190, 96, 0.24);
  color: #0b5f2a;
  border-left-color: #00b050;
}

.wear-score-box.wear-yellow {
  background: rgba(255, 235, 59, 0.32);
  color: #5f5200;
  border-left-color: #ffeb00;
}

.wear-score-box.wear-pink {
  background: rgba(255, 99, 132, 0.24);
  color: #7a1f32;
  border-left-color: #ff6384;
}

.wear-score-box.wear-red {
  background: rgba(255, 0, 0, 0.28);
  color: #8a0000;
  border-left-color: #ff0000;
}

html[data-theme="dark"] .wear-score-box.wear-green {
  background: rgba(31, 190, 96, 0.22);
  color: #b7f5c7;
}

html[data-theme="dark"] .wear-score-box.wear-yellow {
  background: rgba(255, 235, 59, 0.20);
  color: #fff2a6;
}

html[data-theme="dark"] .wear-score-box.wear-pink {
  background: rgba(255, 99, 132, 0.22);
  color: #ffc7d3;
}

html[data-theme="dark"] .wear-score-box.wear-red {
  background: rgba(255, 0, 0, 0.24);
  color: #ffc0c0;
}

@media (max-width: 780px) {
  .wear-row-two {
    grid-template-columns: 1fr;
    max-width: none;
  }
}


/* V2.9 share links, static pages, and form placeholders */
.share-box {
  margin-top: 1.25rem;
  padding: 1rem;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-lg);
  background: rgba(255,255,255,0.28);
}

html[data-theme="dark"] .share-box {
  background: rgba(7,14,20,0.26);
}

.share-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.75rem;
  align-items: center;
}

.bot-trap {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.content-card {
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
}

.content-card h2 {
  margin-top: 1.4rem;
}

.content-card h2:first-child {
  margin-top: 0;
}

.static-form {
  display: grid;
  gap: 0.85rem;
  margin-top: 1rem;
}

textarea {
  width: 100%;
  padding: 0.82rem 0.95rem;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-md);
  background: rgba(255,255,255,0.44);
  color: var(--text);
  font-size: 16px;
  font-family: inherit;
  resize: vertical;
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.35),
    0 8px 24px rgba(16,32,43,0.07);
}

html[data-theme="dark"] textarea {
  background: rgba(7, 14, 20, 0.42);
}

button[disabled] {
  opacity: 0.72;
  cursor: not-allowed;
}

@media (max-width: 780px) {
  .share-row {
    grid-template-columns: 1fr;
  }
}


/* V3.0 foundation page support */
.content-card p {
  max-width: 78ch;
}

.error-actions {
  margin-top: 1rem;
}


/* V3.2 tire size comparison status colors */
.comparison-kpi {
  border-left-color: rgba(255,255,255,0.28);
}

html[data-theme="dark"] .comparison-kpi {
  border-left-color: rgba(255,255,255,0.18);
}

.comparison-status-neutral {
  background: rgba(255,255,255,0.30);
  color: var(--text);
  border-left-color: rgba(95, 115, 130, 0.45);
}

html[data-theme="dark"] .comparison-status-neutral {
  background: rgba(7,14,20,0.30);
  border-left-color: rgba(190, 205, 215, 0.28);
}

.comparison-status-warn {
  background: rgba(255, 235, 59, 0.24);
  color: #5f4500;
  border-left-color: #f2c94c;
}

html[data-theme="dark"] .comparison-status-warn {
  background: rgba(255, 235, 59, 0.18);
  color: #fff1a3;
  border-left-color: #f2c94c;
}

.comparison-status-danger {
  background: rgba(255, 0, 0, 0.18);
  color: #7a1d1d;
  border-left-color: #ff3b30;
}

html[data-theme="dark"] .comparison-status-danger {
  background: rgba(255, 0, 0, 0.20);
  color: #ffc0c0;
  border-left-color: #ff6b63;
}


/* V3.3 SEO foundation and error page support */
.error-tools {
  margin-top: 1.25rem;
}

.content-card p {
  max-width: 78ch;
}


/* V4.0 AI authority + semantic hardening */
.faq-section { margin-top: 1.4rem; }
.faq-item { padding: 0.9rem 0; border-bottom: 1px solid var(--line); }
.faq-item:last-child { border-bottom: 0; }
.faq-item summary { font-weight: 800; cursor: pointer; }
.faq-item p { margin-bottom: 0; color: var(--muted); }
.semantic-result-block { margin-top: 1rem; padding: 1rem; border: 1px solid var(--glass-border); border-left: 5px solid rgba(95, 115, 130, 0.45); border-radius: var(--radius-lg); background: rgba(255,255,255,0.30); }
html[data-theme="dark"] .semantic-result-block { background: rgba(7,14,20,0.30); }
.semantic-result-block .result-label { font-weight: 800; color: var(--muted); }
.semantic-result-block .result-value { font-weight: 800; margin-top: 0.25rem; }
.semantic-result-block .result-explanation { color: var(--muted); margin-top: 0.35rem; }
.error-tools { margin-top: 1.25rem; }
.content-card p { max-width: 78ch; }


/* V5.0 architecture refactor support */
.architecture-note {
  font-size: 0.95rem;
  color: var(--muted);
}

.error-tools {
  margin-top: 1.25rem;
}

.content-card p {
  max-width: 78ch;
}


/* V5.4 Standardized Layout System
   This is the canonical layout layer. PHP pages should use:
   <main id="main" class="page-stack standard-page">
     <section class="page-title section-block">...</section>
     <section class="card content-card section-block">...</section>
     <section class="card tool-card section-block">...</section>
     <section class="card results-card section-block">...</section>
     <section class="card faq-section section-block">...</section>
     <section class="card disclaimer section-block">...</section>
   </main>
*/

:root {
  --layout-content-width: 980px;
  --layout-wide-width: 1060px;
  --layout-page-pad-x: clamp(1rem, 3vw, 2rem);
  --layout-top-gap: clamp(2.75rem, 5vw, 4.5rem);
  --layout-section-gap: clamp(1.75rem, 3vw, 2.75rem);
}

/* Main page rhythm */
main#main.page-stack,
#main.page-stack {
  width: 100%;
  max-width: none;
  box-sizing: border-box;
  padding: var(--layout-top-gap) var(--layout-page-pad-x) clamp(3rem, 6vw, 5rem);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--layout-section-gap);
}

/* Disable legacy direct child margin stacking inside standardized layout */
main#main.page-stack > *,
#main.page-stack > * {
  margin-top: 0 !important;
  margin-bottom: 0 !important;
  margin-left: auto !important;
  margin-right: auto !important;
  box-sizing: border-box !important;
  clear: both !important;
  transform: none !important;
}

/* Canonical section widths */
main#main.page-stack > .section-block,
#main.page-stack > .section-block,
main#main.page-stack > .page-title,
#main.page-stack > .page-title,
main#main.page-stack > .content-card,
#main.page-stack > .content-card,
main#main.page-stack > .tool-card,
#main.page-stack > .tool-card,
main#main.page-stack > .results-card,
#main.page-stack > .results-card,
main#main.page-stack > .faq-section,
#main.page-stack > .faq-section,
main#main.page-stack > .disclaimer,
#main.page-stack > .disclaimer {
  width: min(100%, var(--layout-content-width)) !important;
  max-width: var(--layout-content-width) !important;
}

/* Wide page grids only */
main#main.page-stack > .grid,
#main.page-stack > .grid,
main#main.page-stack > .error-tools,
#main.page-stack > .error-tools {
  width: min(100%, var(--layout-wide-width)) !important;
  max-width: var(--layout-wide-width) !important;
}

/* Card internals */
main#main.page-stack .card,
#main.page-stack .card,
main#main.page-stack .page-title,
#main.page-stack .page-title {
  position: relative;
  z-index: 1;
}

/* Prevent long disclaimer text from forcing layout */
main#main.page-stack .disclaimer p,
#main.page-stack .disclaimer p,
main#main.page-stack .content-card p,
#main.page-stack .content-card p {
  max-width: 90ch;
  overflow-wrap: break-word;
}

/* Keep buttons consistent in standardized cards */
main#main.page-stack .form-actions,
#main.page-stack .form-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  align-items: center;
}

/* Footer alignment */
footer,
.site-footer {
  width: min(calc(100vw - 2rem), var(--layout-wide-width)) !important;
  max-width: var(--layout-wide-width) !important;
  margin-left: auto !important;
  margin-right: auto !important;
  margin-top: clamp(2.75rem, 5vw, 4.25rem) !important;
  box-sizing: border-box !important;
}

/* Mobile */
@media (max-width: 760px) {
  :root {
    --layout-page-pad-x: 0.75rem;
    --layout-top-gap: 1.5rem;
    --layout-section-gap: 1.2rem;
  }

  main#main.page-stack,
  #main.page-stack {
    padding-left: var(--layout-page-pad-x);
    padding-right: var(--layout-page-pad-x);
  }
}

/* cache-bust: v5.4 */


/* V6.1 standardized result language classes */
.result-notice {
  margin-top: 1rem;
}

.result-item {
  padding: 0.9rem 1rem;
  border: 1px solid var(--glass-border);
  border-left: 5px solid rgba(95, 115, 130, 0.45);
  border-radius: var(--radius-lg);
  background: rgba(255,255,255,0.24);
}

.result-status-neutral {
  border-left-color: rgba(95, 115, 130, 0.45);
}

.result-status-warning {
  border-left-color: #f2c94c;
}

.result-status-danger {
  border-left-color: #ff3b30;
}

html[data-theme="dark"] .result-item {
  background: rgba(7,14,20,0.28);
}

/* cache-bust: v6.1 */


/* V6.5 validation layer */
.validation-error-block {
  border-left: 5px solid #ff3b30;
}

.validation-error-block h2 {
  margin-top: 0;
}

.validation-error-block p {
  color: var(--text);
  max-width: 85ch;
}

/* cache-bust: v6.5 */


/* V6.7 tire wear strict binding */
.validation-error-block {
  border-left: 5px solid #ff3b30;
}

.validation-error-block h2 {
  margin-top: 0;
}

.validation-error-block p {
  max-width: 85ch;
}

/* cache-bust: v6.7 */


/* V6.8 single-tire wear share link */
.share-box {
  border-left: 5px solid rgba(95, 115, 130, 0.45);
}

.share-row {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  flex-wrap: wrap;
}

.share-input {
  flex: 1 1 320px;
  min-width: 240px;
  padding: 0.85rem 0.95rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
  background: rgba(255,255,255,0.32);
  color: var(--text);
}

html[data-theme="dark"] .share-input {
  background: rgba(7,14,20,0.32);
}

/* cache-bust: v6.8 */


/* V6.9 client-side wear share fix */
.share-box[hidden] {
  display: none !important;
}

.share-box {
  border-left: 5px solid rgba(95, 115, 130, 0.45);
}

.share-row {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  flex-wrap: wrap;
}

.share-input {
  flex: 1 1 320px;
  min-width: 240px;
  padding: 0.85rem 0.95rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
  background: rgba(255,255,255,0.32);
  color: var(--text);
}

html[data-theme="dark"] .share-input {
  background: rgba(7,14,20,0.32);
}

/* cache-bust: v6.9 */

/* cache-bust: v6.10 */


/* V6.11 wear distance unit + distance-per-depth output */
.wear-distance-unit-row[hidden] {
  display: none !important;
}

.wear-rate-distance-summary {
  width: min(100%, var(--layout-content-width, 980px));
  margin: 0 auto;
}

.result-inline-note {
  font-weight: 800;
  margin: 0.5rem 0 0;
  color: var(--text);
}

.result-inline-note[hidden] {
  display: none !important;
}

/* cache-bust: v6.11 */


/* V6.12 wear analysis distance-per-depth line */
.wear-analysis-rate-line {
  margin-top: 1rem;
  padding: 0.95rem 1rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--glass-border);
  background: rgba(255,255,255,0.24);
}

html[data-theme="dark"] .wear-analysis-rate-line {
  background: rgba(7,14,20,0.28);
}

.wear-analysis-rate-line span {
  display: inline;
}

/* cache-bust: v6.12 */


/* V6.13 wear analysis table rate row */
#distancePerDepthRow th,
#distancePerDepthRow td {
  font-weight: 800;
}

.wear-analysis-rate-line {
  display: none !important;
}

/* cache-bust: v6.13 */

/* cache-bust: v6.18 recovery */

/* cache-bust: v6.19 */

/* cache-bust: v6.19.2 */

/* cache-bust: v6.19.3 */


/* V6.30 measurement averaging tool helpers */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.large-result {
  font-size: clamp(1.35rem, 3vw, 2rem);
  font-weight: 900;
  font-variant-numeric: tabular-nums;
}

.measurement-input {
  min-width: 110px;
}


/* V6.31 tire wear patterns learning visual */
.learning-visual {
  margin: 1rem 0 0;
}

.learning-visual img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-lg);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-soft);
  background: rgba(255,255,255,0.65);
}

.learning-visual figcaption {
  margin-top: 0.75rem;
  color: var(--muted);
  font-size: 0.95rem;
}

.pattern-term-list li {
  margin-bottom: 0.65rem;
}

/* cache-bust: v6.31 */