:root {
  color-scheme: dark;

  --color-bg: #0a0f1a;
  --color-surface: #121a2a;
  --color-border: #243046;
  --color-border-strong: #66789a;
  --color-text: #eef2f8;
  --color-muted: #9aa8bd;
  --color-blue: #2280fc;
  --color-link: #8db6ff;
  --color-warm: #f2b866;

  --font-display: "Newsreader", Georgia, serif;
  --font-ui: "IBM Plex Sans", system-ui, sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-ui);
  line-height: 1.5;
}

a {
  color: var(--color-link);
}

a:focus-visible,
button:focus-visible,
input:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--color-blue);
  outline-offset: 2px;
}

.topbar,
main,
footer {
  max-width: 68rem;
  margin: 0 auto;
  padding-inline: 2rem;
}

.topbar {
  padding-block: 1.25rem;
}

.topbar img {
  display: block;
  width: 11rem;
  height: auto;
}

main {
  padding-block: 1.5rem 3rem;
}

h1 {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2.375rem, 1.5rem + 3vw, 3.5rem);
  font-weight: 400;
  letter-spacing: -0.01em;
  line-height: 1.08;
}

.lede {
  max-width: 44rem;
  margin: 1rem 0 0;
  color: var(--color-muted);
  font-size: 1.0625rem;
}

.layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 24rem);
  gap: 2.5rem;
  align-items: start;
  margin-top: 2.5rem;
}

fieldset {
  margin: 0 0 1.5rem;
  padding: 1rem 0 0;
  border: 0;
  border-top: 1px solid var(--color-border-strong);
}

legend {
  padding: 0 0.75rem 0 0;
  font-weight: 600;
}

label {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 8rem;
  gap: 0 1rem;
  align-items: center;
  padding-block: 0.5rem;
  font-weight: 500;
}

label span {
  grid-column: 1;
  color: var(--color-muted);
  font-size: 0.875rem;
  font-weight: 400;
}

label input {
  grid-column: 2;
  grid-row: 1 / span 2;
  width: 100%;
  min-height: 2.75rem;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--color-border-strong);
  border-radius: 6px;
  background: var(--color-surface);
  color: var(--color-text);
  font: inherit;
  font-size: 1.0625rem;
  text-align: right;
}

.quiet {
  min-height: 2.75rem;
  padding: 0.5rem 1rem;
  border: 1px solid var(--color-border-strong);
  border-radius: 6px;
  background: none;
  color: var(--color-text);
  font: inherit;
  cursor: pointer;
}

.quiet:hover {
  background: var(--color-surface);
}

.results {
  position: sticky;
  top: 1.5rem;
  padding: 1.5rem;
  border: 1px solid var(--color-border-strong);
  border-radius: 10px;
  background: var(--color-surface);
}

h2 {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
}

.total {
  margin: 0.5rem 0 0;
  font-family: var(--font-display);
  font-size: 3rem;
  font-variant-numeric: lining-nums;
  line-height: 1.1;
  overflow-wrap: anywhere;
}

.total span {
  font-size: 1.25rem;
}

.monthly {
  margin: 0.25rem 0 0;
  color: var(--color-muted);
}

dl {
  margin: 1.25rem 0;
  border-top: 1px solid var(--color-border);
}

dl div {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-block: 0.625rem;
  border-bottom: 1px solid var(--color-border);
}

dt {
  color: var(--color-muted);
}

dd {
  margin: 0;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}

.recoverable {
  margin: 0 0 1.25rem;
}

.button {
  display: block;
  padding: 0.75rem 1.25rem;
  border-radius: 6px;
  background: var(--color-blue);
  color: var(--color-bg);
  font-weight: 600;
  text-align: center;
  text-decoration: none;
}

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

.small {
  margin: 0.5rem 0 0;
  color: var(--color-muted);
  font-size: 0.875rem;
}

.assumptions {
  max-width: 44rem;
  margin-top: 2rem;
  color: var(--color-muted);
}

.assumptions summary {
  padding-block: 0.625rem;
  color: var(--color-link);
  cursor: pointer;
}

footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 0.5rem 2rem;
  padding-block: 1.5rem 2.5rem;
  color: var(--color-muted);
  font-size: 0.875rem;
}

footer p {
  margin: 0;
}

footer a {
  display: inline-block;
  padding-block: 0.75rem;
  margin-block: -0.75rem;
}

@media (max-width: 60rem) {
  .layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 1.5rem;
  }

  .results {
    position: static;
  }
}

@media (max-width: 48rem) {
  .topbar,
  main,
  footer {
    padding-inline: 1rem;
  }

  .topbar img {
    width: 9.5rem;
  }

  label {
    grid-template-columns: minmax(0, 1fr) 6.5rem;
  }
}