/* One family, one accent. Numbers are the main visual element. */

:root {
  --bg: #f3f4f1;
  --surface: #ffffff;
  --ink: #15181b;
  --muted: #5d6569;
  --line: #dcdfdb;
  --accent: #0b7a5a;
  --accent-strong: #08664b;
  --accent-ink: #ffffff;
  --warn: #9a5800;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #101312;
    --surface: #181c1b;
    --ink: #e9ecea;
    --muted: #9aa29e;
    --line: #2a302e;
    --accent: #43c495;
    --accent-strong: #5ad3a7;
    --accent-ink: #052a1d;
    --warn: #e0a54a;
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--ink);
  font: 400 1rem/1.5 var(--font);
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.container {
  width: 100%;
  max-width: 70rem;
  margin-inline: auto;
  padding-inline: 20px;
}

/* Header */

.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding-block: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 600;
  font-size: 1.0625rem;
  letter-spacing: -0.01em;
  text-decoration: none;
}

.brand__mark {
  width: 28px;
  height: 28px;
  flex: none;
}

.brand__mark rect {
  fill: var(--accent);
}

.brand__mark path {
  fill: none;
  stroke: var(--accent-ink);
  stroke-width: 2.4;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* Language switcher: same pill language as the calculator toggle. */

.langs {
  display: flex;
  gap: 2px;
  padding: 3px;
  border: 1px solid var(--line);
  border-radius: 12px;
}

.langs__link {
  padding: 5px 9px;
  border-radius: 9px;
  color: var(--muted);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  text-decoration: none;
}

.langs__link:hover {
  color: var(--ink);
}

.langs__link[aria-current="true"] {
  background: var(--surface);
  color: var(--ink);
  box-shadow: 0 0 0 1px var(--line);
}

/* Layout */

.main {
  flex: 1;
  display: grid;
  gap: 40px;
  align-content: center;
  padding-block: 24px 56px;
}

/* Intro and rate board */

h1 {
  margin: 0 0 12px;
  max-width: 14ch;
  font-size: clamp(1.875rem, 1.3rem + 2.4vw, 2.75rem);
  font-weight: 600;
  line-height: 1.1;
  letter-spacing: -0.025em;
  text-wrap: balance;
}

.lead {
  margin: 0 0 36px;
  max-width: 36ch;
  color: var(--muted);
  font-size: 1.0625rem;
}

.board {
  display: grid;
  grid-template-columns: 1fr 1fr;
  margin: 0;
  border-block: 1px solid var(--line);
}

.board__cell {
  min-width: 0;
  padding-block: 20px 22px;
}

.board__cell + .board__cell {
  padding-left: 20px;
  border-left: 1px solid var(--line);
}

.board dt {
  margin-bottom: 6px;
  color: var(--muted);
  font-size: 0.9375rem;
}

.board dd {
  margin: 0;
}

.board__price {
  display: flex;
  align-items: baseline;
  gap: 6px;
  white-space: nowrap;
}

.board__value {
  font-size: clamp(2.25rem, 1.4rem + 4vw, 4rem);
  font-weight: 600;
  line-height: 1;
  letter-spacing: -0.035em;
  font-variant-numeric: tabular-nums;
}

.board__unit {
  color: var(--muted);
  font-size: clamp(1.125rem, 0.9rem + 1.2vw, 1.75rem);
  font-weight: 500;
}

.board dd.board__note {
  margin-top: 10px;
  color: var(--muted);
  font-size: 0.875rem;
}

.status {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin: 14px 0 0;
  color: var(--muted);
  font-size: 0.875rem;
}

.status::before {
  content: "";
  flex: none;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--accent);
  transform: translateY(-1px);
}

.status.is-stale {
  color: var(--warn);
}

.status.is-stale::before {
  background: var(--warn);
}

/* Calculator */

.calc {
  padding: 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 24px;
}

.toggle {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4px;
  margin-bottom: 16px;
  padding: 4px;
  background: var(--bg);
  border-radius: 14px;
}

.toggle__btn {
  appearance: none;
  padding: 10px 8px;
  border: 0;
  border-radius: 10px;
  white-space: nowrap;
  background: transparent;
  color: var(--muted);
  font: inherit;
  font-size: 0.9375rem;
  font-weight: 500;
  cursor: pointer;
}

.toggle__btn:hover {
  color: var(--ink);
}

.toggle__btn[aria-pressed="true"] {
  background: var(--surface);
  color: var(--ink);
  box-shadow: 0 0 0 1px var(--line);
}

.field {
  padding: 12px 16px 10px;
  border: 1px solid var(--line);
  border-radius: 16px;
}

.field + .field {
  margin-top: 8px;
}

.field:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 18%, transparent);
}

.field__label {
  display: block;
  color: var(--muted);
  font-size: 0.875rem;
}

.field__row {
  display: flex;
  align-items: baseline;
  gap: 12px;
}

.field__input {
  flex: 1;
  min-width: 0;
  width: 100%;
  padding: 2px 0 0;
  border: 0;
  background: transparent;
  color: var(--ink);
  font: inherit;
  font-size: clamp(1.75rem, 1.45rem + 1.3vw, 2.25rem);
  font-weight: 600;
  letter-spacing: -0.02em;
  font-variant-numeric: tabular-nums;
}

.field__input:focus-visible {
  outline: none;
}

.field__input::placeholder {
  color: var(--line);
}

.field__cur {
  flex: none;
  color: var(--muted);
  font-weight: 600;
}

.calc__meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 4px 16px;
  margin: 12px 4px 20px;
  color: var(--muted);
  font-size: 0.875rem;
  font-variant-numeric: tabular-nums;
}

.calc__limits.is-warn {
  color: var(--warn);
}

.cta {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 56px;
  padding: 0 24px;
  border-radius: 16px;
  background: var(--accent);
  color: var(--accent-ink);
  font-size: 1.0625rem;
  font-weight: 600;
  text-decoration: none;
}

.cta:hover {
  background: var(--accent-strong);
}

.cta__note {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: 0.8125rem;
  text-align: center;
}

.notice {
  margin: 0;
  padding: 14px 16px;
  border-radius: 14px;
  background: var(--bg);
  color: var(--muted);
  font-size: 0.9375rem;
}

/* Sections below the fold */

.section-title {
  margin: 0 0 20px;
  font-size: clamp(1.375rem, 1.1rem + 1vw, 1.75rem);
  font-weight: 600;
  letter-spacing: -0.02em;
}

/* FAQ: native <details>, one hairline between questions. */

.faq,
.reviews {
  padding-block: 8px 56px;
}

.faq__list {
  max-width: 48rem;
  border-top: 1px solid var(--line);
}

.faq__item {
  border-bottom: 1px solid var(--line);
}

.faq__question {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  padding-block: 18px;
  font-size: 1.0625rem;
  font-weight: 600;
  list-style: none;
  cursor: pointer;
}

.faq__question::-webkit-details-marker {
  display: none;
}

.faq__question::after {
  content: "+";
  flex: none;
  color: var(--muted);
  font-size: 1.375rem;
  font-weight: 400;
  line-height: 1;
}

.faq__item[open] > .faq__question::after {
  transform: rotate(45deg);
}

.faq__question:hover {
  color: var(--accent);
}

.faq__answer {
  padding-bottom: 20px;
  color: var(--muted);
}

.faq__answer p {
  margin: 0;
  max-width: 65ch;
}

/* 1, 2 or 4 columns: rows of reviews always fill evenly on 4 and 8 cards. */
.reviews__list {
  display: grid;
  gap: 12px;
}

.review {
  display: flex;
  flex-direction: column;
  gap: 12px;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 20px;
}

.review__stars {
  margin: 0;
  color: var(--accent);
  font-size: 0.9375rem;
  letter-spacing: 0.12em;
  line-height: 1;
}

.review__stars-empty {
  color: var(--line);
}

.review__text {
  flex: 1;
  margin: 0;
}

.review__text p {
  margin: 0;
  max-width: 60ch;
}

.review__note {
  margin: -4px 0 0;
  color: var(--muted);
  font-size: 0.8125rem;
}

.review__meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 4px 12px;
  color: var(--muted);
  font-size: 0.875rem;
}

.review__name {
  color: var(--ink);
  font-weight: 600;
}

/* Footer */

.site-footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 24px;
  padding-block: 24px 32px;
  color: var(--muted);
  font-size: 0.875rem;
}

.site-footer a {
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--ink);
  text-decoration: underline;
}

/* A changed rate briefly takes the accent colour, so the update is noticed. */
@media (prefers-reduced-motion: no-preference) {
  .board__value.is-updated {
    animation: rate-updated 1.6s ease-out;
  }

  .faq__question::after {
    transition: transform 0.2s ease;
  }

  .toggle__btn,
  .cta {
    transition:
      background-color 0.15s ease,
      color 0.15s ease;
  }
}

@keyframes rate-updated {
  from {
    color: var(--accent);
  }
  to {
    color: var(--ink);
  }
}

@media (min-width: 640px) {
  .container {
    padding-inline: 32px;
  }

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

  .board__cell + .board__cell {
    padding-left: 32px;
  }

  .calc {
    padding: 28px;
  }
}

@media (min-width: 1024px) {
  .reviews__list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (min-width: 960px) {
  .main {
    grid-template-columns: minmax(0, 1fr) 26rem;
    column-gap: clamp(48px, 7vw, 112px);
    align-items: center;
    padding-block: 40px 96px;
  }

  .lead {
    margin-bottom: 48px;
  }
}