@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&display=swap');

:root {
  color-scheme: dark;
  --color-background: #1c1917;
  --color-surface: #292524;
  --color-surface-raised: #332e2b;
  --color-primary: #ea580c;
  --color-primary-active: #c2410c;
  --color-accent: #2563eb;
  --color-on-primary: #ffffff;
  --color-foreground: #ffffff;
  --color-muted: #d6d3d1;
  --color-subtle: #a8a29e;
  --color-border: rgba(255, 255, 255, 0.16);
  --color-danger: #fecaca;
  --color-danger-border: #dc2626;
  --color-ring: #fb923c;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.22);
  --shadow-md: 0 10px 24px rgba(0, 0, 0, 0.22);
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  font-family: 'Plus Jakarta Sans', ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; min-width: 320px; background: var(--color-background); color: var(--color-foreground); font-size: 1rem; line-height: 1.6; }
a { color: inherit; }
button, input, select { font: inherit; }
button, a { touch-action: manipulation; }
button { cursor: pointer; }
.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; }
.skip-link { position: absolute; z-index: 10; left: var(--space-md); top: -4rem; padding: var(--space-sm) var(--space-md); background: #fff; color: #1c1917; border-radius: 0 0 8px 8px; }
.skip-link:focus { top: 0; }
.site-header { border-bottom: 1px solid var(--color-border); }
.header-inner, .container { width: min(100% - 2rem, 72rem); margin-inline: auto; }
.header-inner { min-height: 4.5rem; display: flex; align-items: center; justify-content: space-between; gap: var(--space-md); }
.brand { display: inline-flex; align-items: center; gap: 0.625rem; color: var(--color-foreground); text-decoration: none; font-size: 1.15rem; font-weight: 800; letter-spacing: -0.03em; }
.brand-mark { display: grid; place-items: center; width: 2rem; height: 2rem; background: var(--color-primary); color: #fff; border-radius: 0.5rem; box-shadow: var(--shadow-sm); }
.brand-mark svg { width: 1.2rem; height: 1.2rem; }
.site-nav { display: flex; gap: var(--space-md); font-size: 0.875rem; font-weight: 700; }
.site-nav a { color: var(--color-muted); text-underline-offset: 0.25rem; }
.site-nav a:hover { color: #fff; }
.hero { padding: var(--space-xl) 0 var(--space-2xl); }
.breadcrumbs { display: flex; flex-wrap: wrap; gap: 0.4rem; color: var(--color-subtle); font-size: 0.875rem; }
.breadcrumbs a { color: var(--color-muted); }
.eyebrow, .result-kicker { margin: var(--space-lg) 0 var(--space-sm); color: #fdba74; font-size: 0.8125rem; font-weight: 800; letter-spacing: 0.08em; text-transform: uppercase; }
h1, h2, h3, p { margin-top: 0; }
h1 { max-width: 13ch; margin-bottom: var(--space-md); font-size: clamp(2.5rem, 10vw, 4.75rem); line-height: 0.98; letter-spacing: -0.06em; }
h2 { font-size: clamp(1.5rem, 5vw, 2.1rem); line-height: 1.15; letter-spacing: -0.035em; }
h3 { font-size: 1.05rem; }
.lede { max-width: 60ch; color: var(--color-muted); font-size: 1.0625rem; }
.benefit-list { display: flex; flex-wrap: wrap; gap: var(--space-sm) var(--space-md); margin: var(--space-lg) 0 0; padding: 0; list-style: none; color: #e7e5e4; font-size: 0.9rem; font-weight: 600; }
.benefit-list li::before { content: '✓'; margin-right: 0.4rem; color: #fb923c; }
.calculator-card, .content-card, .affiliate-box, .result-panel { border: 1px solid var(--color-border); border-radius: 1rem; background: var(--color-surface); box-shadow: var(--shadow-md); }
.calculator-card { overflow: hidden; }
.calculator-heading { padding: var(--space-lg); border-bottom: 1px solid var(--color-border); }
.calculator-heading p { margin-bottom: 0; color: var(--color-muted); }
.calculator-form { padding: var(--space-lg); }
fieldset { min-width: 0; margin: 0 0 var(--space-lg); padding: 0; border: 0; }
legend, label { font-weight: 700; }
legend { margin-bottom: var(--space-sm); }
.shape-selector { padding-bottom: var(--space-lg); border-bottom: 1px solid var(--color-border); }
.shape-toggle { display: grid; gap: var(--space-sm); }
.shape-description { min-height: 2.8rem; margin: var(--space-sm) 0 0; color: var(--color-subtle); font-size: 0.875rem; }
.unit-toggle { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-sm); }
.toggle-option { position: relative; display: grid; min-height: 3rem; place-items: center; padding: 0.75rem var(--space-md); border: 1px solid var(--color-border); border-radius: 0.625rem; color: var(--color-muted); font-size: 0.925rem; font-weight: 700; line-height: 1.3; text-align: center; cursor: pointer; transition: background-color 180ms ease, border-color 180ms ease, color 180ms ease; }
.toggle-option:hover { border-color: rgba(251, 146, 60, 0.7); color: #fff; }
.toggle-option:has(input:checked) { border-color: #fb923c; background: rgba(234, 88, 12, 0.2); color: #fff; }
.toggle-option input { position: absolute; opacity: 0; }
.toggle-option:has(input:focus-visible) { outline: 3px solid var(--color-ring); outline-offset: 3px; }
.form-grid { display: grid; gap: var(--space-md); }
.field { display: grid; gap: var(--space-sm); }
.field[hidden] { display: none; }
.field[data-field-shapes]:not([hidden]) { animation: field-reveal 180ms ease-out; }
@keyframes field-reveal {
  from { opacity: 0; transform: translateY(0.25rem); }
  to { opacity: 1; transform: translateY(0); }
}
.input-wrap { display: grid; grid-template-columns: 1fr auto; min-height: 3rem; overflow: hidden; border: 1px solid #a8a29e; border-radius: 0.625rem; background: #fff; color: #1c1917; transition: border-color 180ms ease, box-shadow 180ms ease; }
.input-wrap:focus-within { border-color: var(--color-ring); box-shadow: 0 0 0 3px rgba(251, 146, 60, 0.35); }
.input-wrap input, .input-wrap select { min-width: 0; min-height: 3rem; padding: 0.75rem 0.875rem; border: 0; outline: 0; background: transparent; color: #1c1917; }
.input-wrap select { width: 100%; cursor: pointer; }
.input-wrap--select { grid-template-columns: 1fr; }
.input-suffix { display: grid; min-width: 3.1rem; place-items: center; padding-inline: var(--space-sm); border-left: 1px solid #d6d3d1; color: #57534e; font-size: 0.875rem; font-weight: 700; }
.field-help, .field-error, .form-error, .result-support, .result-stat small, .math-line { font-size: 0.875rem; }
.field-help { color: var(--color-subtle); }
.field-error, .form-error { min-height: 1.35rem; margin: 0; color: var(--color-danger); font-weight: 600; }
.button-primary { display: inline-flex; width: 100%; min-height: 3rem; align-items: center; justify-content: center; padding: 0.75rem 1rem; border: 1px solid transparent; border-radius: 0.625rem; background: var(--color-accent); color: #fff; font-weight: 800; box-shadow: var(--shadow-sm); transition: transform 180ms ease, background-color 180ms ease, box-shadow 180ms ease; }
.button-primary:hover { background: #1d4ed8; box-shadow: var(--shadow-md); transform: translateY(-1px); }
.button-primary:active { transform: translateY(0); }
:focus-visible { outline: 3px solid var(--color-ring); outline-offset: 3px; }
.result-panel { margin-top: var(--space-lg); padding: var(--space-lg); border-color: rgba(251, 146, 60, 0.65); background: #2f2926; }
.result-panel[hidden] { display: none; }
.result-kicker { margin-top: 0; }
.result-value { margin-bottom: var(--space-xs); font-size: clamp(2rem, 8vw, 3.5rem); font-weight: 800; line-height: 1; letter-spacing: -0.05em; }
.result-value span { font-size: 0.42em; letter-spacing: -0.02em; }
.result-support { color: var(--color-muted); }
.result-grid { display: grid; gap: var(--space-sm); margin: var(--space-lg) 0 var(--space-md); }
.result-stat { min-height: 5.5rem; padding: var(--space-md); border-radius: 0.75rem; background: rgba(255,255,255,0.06); }
.result-stat span, .result-stat small { display: block; color: var(--color-muted); }
.result-stat strong { display: block; margin: 0.15rem 0; color: #fff; font-size: 1.4rem; font-variant-numeric: tabular-nums; }
.math-line { margin-bottom: 0; padding-top: var(--space-md); border-top: 1px solid var(--color-border); color: var(--color-muted); }
.ad-slot { display: grid; min-height: 11.25rem; place-items: center; margin: var(--space-xl) 0; border: 1px dashed rgba(255,255,255,0.25); border-radius: 0.75rem; color: var(--color-subtle); font-size: 0.75rem; font-weight: 700; letter-spacing: 0.08em; text-align: center; text-transform: uppercase; }
.section { padding: var(--space-2xl) 0; }
.section + .section { border-top: 1px solid var(--color-border); }
.section-intro { max-width: 62ch; color: var(--color-muted); }
.content-card, .affiliate-box { padding: var(--space-lg); }
.content-card p:last-child, .affiliate-box p:last-child { margin-bottom: 0; }
.formula { overflow-x: auto; padding: var(--space-md); border-radius: 0.625rem; background: #1c1917; color: #fed7aa; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 0.875rem; }
.faq-list { display: grid; gap: var(--space-sm); }
details { padding: var(--space-md); border: 1px solid var(--color-border); border-radius: 0.625rem; background: rgba(255,255,255,0.03); }
summary { cursor: pointer; font-weight: 700; }
details p { margin: var(--space-md) 0 0; color: var(--color-muted); }
.product-list, .related-list { display: grid; gap: var(--space-sm); margin: var(--space-md) 0 0; padding: 0; list-style: none; }
.product-list a, .related-list a { display: flex; min-height: 2.75rem; align-items: center; justify-content: space-between; gap: var(--space-md); padding: 0.75rem var(--space-md); border: 1px solid var(--color-border); border-radius: 0.625rem; background: rgba(255,255,255,0.04); color: #fff; font-weight: 700; text-decoration: none; transition: background-color 180ms ease, border-color 180ms ease, transform 180ms ease; }
.product-list a::after, .related-list a::after { content: '→'; color: #fdba74; }
.product-list a:hover, .related-list a:hover { border-color: #fb923c; background: rgba(234,88,12,0.14); transform: translateY(-1px); }
.site-footer { padding: var(--space-xl) 0; border-top: 1px solid var(--color-border); color: var(--color-subtle); font-size: 0.875rem; }
.footer-inner { display: flex; flex-wrap: wrap; justify-content: space-between; gap: var(--space-md); }
.base-page { max-width: 68ch; padding: var(--space-3xl) 0; }
.base-page--wide { max-width: none; }
.not-found-page { min-height: calc(100dvh - 9rem); display: grid; align-content: center; }
.not-found-copy { max-width: 44rem; }
.error-code-display { margin-bottom: 0; color: #fdba74; font-size: clamp(5rem, 25vw, 10rem); font-weight: 800; line-height: 0.8; letter-spacing: -0.08em; }
.button-primary--inline { width: auto; margin-top: var(--space-md); padding-inline: var(--space-lg); text-decoration: none; }
.directory-group { margin-top: var(--space-2xl); }
.directory-heading { display: flex; flex-wrap: wrap; align-items: baseline; justify-content: space-between; gap: var(--space-md); }
.directory-heading h2 { margin-bottom: 0; }
.directory-heading a { color: #fdba74; font-weight: 700; text-underline-offset: 0.25rem; }
.tool-directory { display: grid; gap: var(--space-md); margin-top: var(--space-xl); }
.tool-directory a { display: block; padding: var(--space-lg); border: 1px solid var(--color-border); border-radius: 0.75rem; background: var(--color-surface); color: #fff; text-decoration: none; }
.tool-directory a:hover { border-color: #fb923c; }

@media (min-width: 40rem) {
  .header-inner, .container { width: min(100% - 3rem, 72rem); }
  .hero { padding: var(--space-2xl) 0 var(--space-3xl); }
  .calculator-card { display: grid; grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr); }
  .calculator-heading { grid-column: 1 / -1; }
  .calculator-form { border-right: 1px solid var(--color-border); }
  .result-panel { align-self: start; margin: var(--space-lg); }
  .form-grid { grid-template-columns: 1fr 1fr; }
  .field--wide { grid-column: 1 / -1; }
  .result-grid { grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr)); }
  .ad-slot { min-height: 15.625rem; }
  .product-list, .related-list { grid-template-columns: repeat(3, 1fr); }
}

@media (min-width: 64rem) {
  .header-inner, .container { width: min(100% - 4rem, 72rem); }
  .hero { padding-top: 5rem; }
  .section { padding: 4.5rem 0; }
  .shape-toggle { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .shape-option { padding-inline: var(--space-sm); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
}