:root {
  color-scheme: light dark;
  --bg: #050708;
  --bg-grid: rgba(255, 255, 255, 0.04);
  --panel: #0e1317;
  --panel-2: #141b20;
  --panel-strong: #0b1016;
  --text: #f4efe6;
  --muted: #9facb4;
  --line: #25323a;
  --accent: #ff9f1c;
  --accent-strong: #ffb347;
  --accent-soft: rgba(255, 159, 28, 0.16);
  --cyan: #8edee5;
  --field: #0b1016;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.38);
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
  }
}

* {
  box-sizing: border-box;
}

html {
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.5;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at 50% 0%, rgba(255, 159, 28, 0.16), transparent 34rem),
    linear-gradient(var(--bg-grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--bg-grid) 1px, transparent 1px),
    var(--bg);
  background-size: auto, 42px 42px, 42px 42px, auto;
  color: var(--text);
  text-wrap: pretty;
}

a {
  color: inherit;
}

.site-shell {
  width: min(1220px, calc(100% - 32px));
  margin: 0 auto;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  padding: 24px 0 14px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--accent);
  font-weight: 900;
  font-size: 0.9rem;
  letter-spacing: 0.1em;
  text-decoration: none;
  text-transform: uppercase;
}

.brand-mark {
  display: inline-grid;
  place-items: center;
  position: relative;
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 50%;
  background: #0a0f13;
  color: var(--accent);
  font-size: 0.8rem;
  font-weight: 950;
  overflow: hidden;
}

.brand-mark::before,
.brand-mark::after {
  display: none;
}

.topnav,
.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  color: var(--muted);
  font-size: 0.95rem;
}

.topnav a,
.footer-links a {
  border-radius: 999px;
  text-decoration: none;
  padding: 6px 9px;
}

.topnav a:hover,
.footer-links a:hover {
  background: var(--accent-soft);
  color: var(--accent-strong);
}

.calculator-first {
  display: grid;
  grid-template-columns: 390px minmax(0, 1fr);
  gap: 18px;
  align-items: stretch;
  padding: 18px 0 28px;
}

.calculator-card,
.result-card,
.page-card {
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(14, 19, 23, 0.92);
  box-shadow: var(--shadow);
}

.calculator-card,
.result-card {
  padding: clamp(24px, 4vw, 34px);
}

.calculator-card {
  position: relative;
  overflow: hidden;
}

.calculator-card::before {
  display: none;
}

.status-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
}

.status-row span,
.conversion-strip span,
.result-badge {
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--field);
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 850;
  line-height: 1;
  padding: 8px 10px;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--cyan);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 12px;
  font-size: clamp(2.45rem, 5.6vw, 5.6rem);
  line-height: 0.9;
  letter-spacing: -0.045em;
}

h2 {
  font-size: clamp(1.5rem, 3vw, 2.15rem);
  letter-spacing: -0.02em;
}

h3 {
  margin-bottom: 8px;
}

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

.lede {
  max-width: 58ch;
  margin-bottom: 22px;
  font-size: 1rem;
  line-height: 1.55;
}

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

.field-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(120px, 0.68fr);
  gap: 12px;
}

label {
  display: grid;
  gap: 7px;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 760;
}

select,
input {
  width: 100%;
  min-height: 48px;
  border: 1px solid #31404a;
  border-radius: 8px;
  background: #070b0f;
  color: var(--text);
  font: inherit;
  font-weight: 850;
  padding: 10px 12px;
}

select:focus,
input:focus,
button:focus {
  outline: 3px solid var(--accent-soft);
  border-color: var(--accent);
}

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

.field-note {
  margin: -2px 0 0;
  color: var(--muted);
  font-size: 0.88rem;
}

button {
  min-height: 48px;
  border: 1px solid transparent;
  border-radius: 8px;
  font: inherit;
  font-weight: 900;
  cursor: pointer;
  padding: 10px 16px;
  transition: transform 160ms ease, box-shadow 160ms ease, background-color 160ms ease;
}

button:hover {
  transform: translateY(-1px);
}

.primary-button {
  background: var(--accent);
  color: #0d0802;
  box-shadow: 0 0 0 4px rgba(255, 159, 28, 0.15);
}

.primary-button:active {
  transform: translateY(2px);
}

.secondary-button {
  border-color: var(--line);
  background: transparent;
  color: var(--text);
}

.result-card {
  position: relative;
  display: grid;
  align-content: center;
  min-height: 590px;
  overflow: hidden;
  background:
    linear-gradient(rgba(255, 255, 255, 0.032) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.032) 1px, transparent 1px),
    var(--panel);
  background-size: 42px 42px, 42px 42px, auto;
}

.result-card::before {
  content: "";
  position: absolute;
  inset: 38px;
  border: 1px solid rgba(142, 222, 229, 0.2);
  border-radius: 50%;
  transform: scaleX(1.32);
  opacity: 0.55;
  pointer-events: none;
}

.result-card::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: min(52vw, 520px);
  aspect-ratio: 1;
  border-radius: 50%;
  transform: translate(-50%, -50%);
  background:
    linear-gradient(90deg, transparent 49.5%, rgba(255, 159, 28, 0.34) 49.5% 50.5%, transparent 50.5%),
    linear-gradient(transparent 49.5%, rgba(255, 159, 28, 0.34) 49.5% 50.5%, transparent 50.5%);
  opacity: 0.42;
  pointer-events: none;
}

.result-topline {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 36px;
}

.result-label {
  margin-bottom: 0;
  color: var(--cyan);
  font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  font-weight: 900;
  font-size: 0.78rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.result-number {
  position: relative;
  z-index: 1;
  margin-bottom: 18px;
  color: var(--accent);
  font-size: clamp(6rem, 16vw, 11rem);
  font-weight: 1000;
  line-height: 0.82;
  letter-spacing: -0.07em;
  text-shadow: 0 0 42px rgba(255, 159, 28, 0.18);
}

.formula {
  position: relative;
  z-index: 1;
  margin-top: 28px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.95rem;
}

.conversion-strip {
  position: relative;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 24px;
}

.result-card > .muted {
  position: relative;
  z-index: 1;
}

.error {
  margin: 0;
  color: #ff746c;
  font-weight: 800;
}

.content-section {
  margin-bottom: 34px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(14, 19, 23, 0.92);
  color: var(--text);
  box-shadow: var(--shadow);
  padding: clamp(22px, 4vw, 28px);
}

.content-section:not(.compact-section) {
  display: grid;
  grid-template-columns: minmax(220px, 0.7fr) minmax(0, 1.3fr);
  gap: 24px;
  align-items: start;
}

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

.content-section .eyebrow {
  color: var(--accent-strong);
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  padding: 0;
  list-style: none;
}

.steps li {
  border: 1px solid var(--line);
  background: var(--panel-2);
  border-radius: 8px;
  color: var(--muted);
  line-height: 1.45;
  padding: 14px;
}

.steps strong {
  display: block;
  color: var(--text);
  margin-bottom: 5px;
}

.compact-section {
  display: grid;
  grid-template-columns: minmax(220px, 0.82fr) minmax(0, 1.18fr);
  gap: 24px;
  align-items: start;
}

.page-main {
  padding: 24px 0 48px;
}

.page-card {
  padding: clamp(22px, 4vw, 34px);
}

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

.article-list {
  display: grid;
  gap: 12px;
  padding-left: 20px;
}

.site-footer {
  border-top: 1px solid var(--line);
  padding: 24px 0 34px;
  color: var(--muted);
}

.site-footer .site-shell {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  flex-wrap: wrap;
}

@media (max-width: 820px) {
  .topbar,
  .calculator-first,
  .field-grid,
  .steps,
  .compact-section,
  .content-section:not(.compact-section) {
    grid-template-columns: 1fr;
  }

  .topbar {
    align-items: flex-start;
  }

  .calculator-first {
    padding-top: 8px;
  }

  .brand {
    max-width: 180px;
  }

  .topnav {
    justify-content: flex-end;
    max-width: none;
    gap: 4px;
    font-size: 0.9rem;
  }

  .topnav a {
    padding: 4px;
  }

  h1 {
    font-size: clamp(2.3rem, 12vw, 4.2rem);
  }

  .result-card {
    min-height: 460px;
  }

  .result-number {
    font-size: clamp(5rem, 28vw, 7rem);
  }

  .actions {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
  }
}