:root {
  --bg: #050b08;
  --surface: #0b1510;
  --surface-2: #101d16;
  --green: #4df09a;
  --text: #f4f8f5;
  --muted: #9aaba2;
  --line: rgba(255, 255, 255, 0.1);
  --danger: #ff9b91;
}

* {
  box-sizing: border-box;
}

html {
  color-scheme: dark;
}

body {
  min-width: 320px;
  margin: 0;
  background:
    radial-gradient(
      circle at 72% -12%,
      rgba(77, 240, 154, 0.1),
      transparent 32rem
    ),
    var(--bg);
  color: var(--text);
  font:
    16px/1.6 system-ui,
    -apple-system,
    BlinkMacSystemFont,
    'Segoe UI',
    sans-serif;
}

a {
  color: inherit;
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible {
  outline: 2px solid var(--green);
  outline-offset: 3px;
}

.site-header {
  position: sticky;
  z-index: 20;
  top: 0;
  display: flex;
  min-height: 70px;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  border-bottom: 1px solid var(--line);
  background: rgba(5, 11, 8, 0.9);
  padding: 0 max(20px, calc((100vw - 1120px) / 2));
  backdrop-filter: blur(20px);
}

.brand {
  color: #fff;
  font-size: 15px;
  font-weight: 950;
  letter-spacing: -0.04em;
  text-decoration: none;
}

.brand span {
  color: var(--green);
}

.site-header nav {
  display: flex;
  gap: 6px;
  align-items: center;
}

.site-header nav a {
  border-radius: 10px;
  color: rgba(244, 248, 245, 0.66);
  padding: 9px 11px;
  font-size: 13px;
  font-weight: 760;
  text-decoration: none;
}

.site-header nav a:hover,
.site-header nav a[aria-current='page'] {
  background: rgba(77, 240, 154, 0.09);
  color: var(--green);
}

main {
  width: min(1120px, calc(100% - 40px));
  margin: auto;
  padding: 34px 0 96px;
}

.breadcrumbs {
  color: rgba(244, 248, 245, 0.48);
  font-size: 13px;
}

.breadcrumbs a {
  color: var(--green);
  text-decoration: none;
}

.tool-hero {
  max-width: 900px;
  padding: 58px 0 38px;
}

.tool-hero .label {
  margin: 0 0 12px;
  color: var(--green);
  font-size: 11px;
  font-weight: 900;
  letter-spacing: 0.14em;
}

.tool-hero h1 {
  margin: 0;
  font-size: clamp(44px, 7vw, 78px);
  line-height: 0.98;
  letter-spacing: -0.055em;
}

.tool-hero > p:not(.label) {
  max-width: 720px;
  margin: 20px 0 0;
  color: var(--muted);
  font-size: 19px;
}

.tool-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(300px, 0.72fr);
  gap: 16px;
  align-items: start;
}

.tool-panel,
.result-panel,
.explain,
.tool-card {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
}

.tool-panel,
.result-panel,
.explain {
  padding: clamp(22px, 4vw, 34px);
}

.tool-panel h2,
.result-panel h2,
.explain h2 {
  margin: 0 0 18px;
  font-size: 24px;
  letter-spacing: -0.025em;
}

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

.comparison-context {
  margin-bottom: 28px;
}

.comparison-subtitle {
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

label {
  display: grid;
  gap: 7px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 760;
}

input,
select {
  width: 100%;
  min-height: 49px;
  border: 1px solid rgba(255, 255, 255, 0.14);
  border-radius: 10px;
  background: #07100c;
  color: #fff;
  padding: 10px 12px;
  font: inherit;
}

input::placeholder {
  color: rgba(244, 248, 245, 0.42);
}

.calculate {
  min-height: 48px;
  margin-top: 18px;
  border: 0;
  border-radius: 10px;
  background: var(--green);
  color: #06110b;
  padding: 0 18px;
  font: inherit;
  font-weight: 900;
  cursor: pointer;
}

.calculate:active {
  transform: translateY(1px);
}

.result-panel {
  position: sticky;
  top: 88px;
  background:
    linear-gradient(145deg, rgba(77, 240, 154, 0.07), transparent 58%),
    var(--surface-2);
}

.results {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.result {
  display: grid;
  gap: 7px;
  min-height: 102px;
  align-content: center;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(0, 0, 0, 0.15);
  padding: 14px;
}

.result span {
  color: var(--muted);
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.result strong {
  color: var(--green);
  font-size: clamp(20px, 3vw, 29px);
  line-height: 1.1;
}

.form-message {
  min-height: 24px;
  margin: 14px 0 0;
  color: var(--danger);
  font-size: 13px;
}

.explain {
  max-width: 920px;
  margin-top: 46px;
}

.explain p,
.explain li {
  color: var(--muted);
}

.explain h2:not(:first-child) {
  margin-top: 34px;
}

.example-box {
  margin: 18px 0 32px;
  border-left: 3px solid var(--green);
  background: rgba(77, 240, 154, 0.06);
  padding: 18px 20px;
}

.example-box strong,
.formula {
  color: var(--text);
}

.formula {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #07100c;
  padding: 14px 16px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 14px;
}

.faq-list {
  display: grid;
  gap: 8px;
}

.faq-list details {
  border-top: 1px solid var(--line);
  padding: 15px 0;
}

.faq-list details:last-child {
  border-bottom: 1px solid var(--line);
}

.faq-list summary {
  color: var(--text);
  font-weight: 820;
  cursor: pointer;
}

.faq-list details p {
  margin-bottom: 0;
}

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

.related-columns h3 {
  margin: 0 0 10px;
  font-size: 15px;
  letter-spacing: 0.01em;
}

.related-links {
  display: grid;
  gap: 8px;
}

.related-links a {
  color: var(--green);
  font-weight: 760;
  text-underline-offset: 3px;
}

.funnel {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 34px;
}

.funnel a {
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 10px 14px;
  font-weight: 800;
  text-decoration: none;
}

.funnel a:first-child {
  border-color: transparent;
  background: var(--green);
  color: #06110b;
}

.hub-intro {
  max-width: 760px;
}

.tool-groups {
  display: grid;
  gap: 52px;
  margin-top: 28px;
}

.tool-group h2 {
  margin: 0 0 16px;
  font-size: clamp(28px, 4vw, 42px);
  letter-spacing: -0.04em;
}

.tool-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.tool-card {
  display: grid;
  gap: 12px;
  min-height: 190px;
  align-content: space-between;
  padding: 24px;
  text-decoration: none;
}

.tool-card:hover {
  border-color: rgba(77, 240, 154, 0.38);
  background: var(--surface-2);
}

.tool-card h3 {
  margin: 0;
  font-size: 23px;
}

.tool-card p {
  margin: 8px 0 0;
  color: var(--muted);
}

.tool-card > span {
  color: var(--green);
  font-weight: 850;
}

.site-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  padding: 28px max(20px, calc((100vw - 1120px) / 2));
  font-size: 13px;
}

@media (max-width: 760px) {
  .site-header {
    position: static;
    display: grid;
    justify-items: center;
    justify-content: center;
    padding-block: 15px;
  }

  .site-header nav {
    flex-wrap: nowrap;
    justify-content: center;
  }

  .site-header nav a {
    padding: 7px 8px;
    font-size: 11px;
  }

  main {
    width: min(100% - 28px, 1120px);
    padding-top: 24px;
  }

  .tool-hero {
    padding-top: 40px;
  }

  .tool-hero h1 {
    font-size: clamp(40px, 12vw, 58px);
  }

  .tool-layout,
  .tool-grid,
  .field-grid,
  .related-columns {
    grid-template-columns: 1fr;
  }

  .result-panel {
    position: static;
  }
}

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