:root {
  --brand: #5d92d2;
  --brand-dark: #326daF;
  --brand-soft: #eaf2fb;
  --ink: #15191f;
  --muted: #5c6570;
  --border: #dfe4ea;
  --surface: #ffffff;
  --canvas: #f5f7f9;
  --success: #24734b;
  --success-soft: #e7f4ed;
  --danger: #b42318;
  --shadow: 0 18px 48px rgba(27, 45, 68, 0.10);
  --radius-lg: 24px;
  --radius-md: 16px;
  --content: 1080px;
}

* { box-sizing: border-box; }

html { color-scheme: light; scroll-behavior: smooth; }

body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  background: var(--canvas);
  color: var(--ink);
  font-family: Montserrat, "Avenir Next", Avenir, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

button, input { font: inherit; }
button, summary { touch-action: manipulation; }

.skip-link {
  position: fixed;
  z-index: 100;
  top: 12px;
  left: 12px;
  padding: 10px 14px;
  background: var(--ink);
  color: white;
  border-radius: 8px;
  transform: translateY(-150%);
}
.skip-link:focus { transform: translateY(0); }

.site-header {
  background: var(--surface);
  border-bottom: 1px solid rgba(21, 25, 31, 0.08);
}

.header-inner {
  width: min(calc(100% - 32px), var(--content));
  min-height: 102px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand { display: inline-flex; align-items: center; }
.brand img { width: 155px; height: auto; display: block; }
.header-label {
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.page-shell {
  width: min(calc(100% - 32px), var(--content));
  margin: 0 auto;
  padding: 72px 0 64px;
}

.intro { max-width: 860px; margin-bottom: 36px; }
.eyebrow {
  margin: 0 0 8px;
  color: var(--brand-dark);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

h1, h2, h3, p { margin-top: 0; }
h1 {
  margin-bottom: 12px;
  font-size: clamp(2.25rem, 7vw, 4.5rem);
  line-height: 0.98;
  letter-spacing: -0.045em;
  text-wrap: balance;
}
.intro > p:last-child { max-width: 620px; margin-bottom: 0; color: var(--muted); font-size: 1.08rem; }

.input-panel {
  position: relative;
  overflow: hidden;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 0.8fr);
  gap: 48px;
  align-items: center;
  padding: 40px;
  background: var(--brand);
  color: white;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
}

.input-panel::after {
  content: "";
  position: absolute;
  right: -120px;
  bottom: -170px;
  width: 350px;
  height: 350px;
  border: 72px solid rgba(255, 255, 255, 0.09);
  border-radius: 50%;
  pointer-events: none;
}

.input-copy, .field-wrap { position: relative; z-index: 1; }
.step {
  display: inline-flex;
  margin-bottom: 12px;
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  opacity: 0.82;
}
.input-copy h2 { margin-bottom: 8px; font-size: clamp(1.55rem, 3vw, 2.25rem); line-height: 1.1; }
.input-copy p { margin-bottom: 0; opacity: 0.86; }
.field-wrap label { display: block; margin-bottom: 8px; font-weight: 700; }
.money-input {
  display: flex;
  align-items: center;
  min-height: 68px;
  background: white;
  border: 3px solid transparent;
  border-radius: 14px;
  transition: border-color 180ms ease, box-shadow 180ms ease;
}
.money-input:focus-within { border-color: #173d69; box-shadow: 0 0 0 4px rgba(255,255,255,0.30); }
.money-input input {
  width: 100%;
  min-width: 0;
  padding: 14px 6px 14px 18px;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--ink);
  font-size: clamp(1.35rem, 4vw, 1.8rem);
  font-weight: 750;
  font-variant-numeric: tabular-nums;
}
.money-input span { padding: 0 18px 0 8px; color: var(--brand-dark); font-size: 1.45rem; font-weight: 800; }
.field-wrap small { display: block; margin-top: 8px; opacity: 0.85; }
.field-error { min-height: 1.55em; margin: 4px 0 0; color: #fff4f2; font-size: 0.9rem; font-weight: 700; }
.field-wrap.has-error .money-input { border-color: #7f1d1d; }

.results { margin-top: 64px; }
.section-heading { display: flex; align-items: end; justify-content: space-between; gap: 20px; margin-bottom: 24px; }
.section-heading h2 { margin-bottom: 0; font-size: clamp(1.6rem, 4vw, 2.4rem); line-height: 1.1; }
.text-button {
  min-height: 44px;
  padding: 8px 4px;
  border: 0;
  border-bottom: 2px solid currentColor;
  background: transparent;
  color: var(--brand-dark);
  font-weight: 750;
  cursor: pointer;
}
.text-button:hover { color: var(--ink); }
.text-button:focus-visible, summary:focus-visible, .brand:focus-visible { outline: 3px solid var(--brand); outline-offset: 4px; }

.summary-card, .operation-card, .final-card, .formula-note {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
}

.summary-card {
  display: grid;
  grid-template-columns: 1fr auto minmax(260px, 0.7fr);
  align-items: center;
  gap: 24px;
  padding: 28px 32px;
}
.summary-card > div:first-child { display: flex; flex-direction: column; }
.summary-card span { font-weight: 700; }
.summary-card small { color: var(--muted); }
.summary-total {
  padding-left: 30px;
  border-left: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  text-align: right;
}
.amount, dd {
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.025em;
}
.amount { font-size: 1.25rem; }
.amount-large { font-size: clamp(1.65rem, 5vw, 2.35rem); line-height: 1.15; }

.operation-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 20px; }
.operation-card { overflow: hidden; }
.operation-card header { display: flex; gap: 16px; align-items: center; padding: 24px 26px; background: var(--brand-soft); }
.operation-number { color: var(--brand-dark); font-size: 1.85rem; font-weight: 300; letter-spacing: -0.05em; }
.operation-card h3 { margin-bottom: 0; font-size: 1.2rem; }
.operation-card header p { margin-bottom: 0; color: var(--muted); font-size: 0.9rem; }
dl { margin: 0; padding: 12px 26px 20px; }
dl > div { min-height: 50px; display: flex; align-items: center; justify-content: space-between; gap: 20px; border-bottom: 1px solid var(--border); }
dt { color: var(--muted); }
dd { margin: 0; font-weight: 750; text-align: right; }
dl > .operation-total { margin-top: 8px; border-bottom: 0; color: var(--ink); }
.operation-total dt { color: var(--ink); font-weight: 800; }
.operation-total dd { color: var(--brand-dark); font-size: 1.15rem; }

.final-card {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 28px;
  margin-top: 20px;
  padding: 30px 32px;
  border-color: #bdd1ea;
  box-shadow: 0 12px 34px rgba(50,109,175,0.08);
}
.final-card > div:first-child { display: flex; flex-direction: column; }
.final-card > div:first-child > span { font-weight: 800; }
.check-status {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 9px 14px;
  border-radius: 999px;
  background: #edf0f3;
  color: var(--muted);
  font-size: 0.88rem;
  font-weight: 750;
}
.check-status[data-state="valid"] { background: var(--success-soft); color: var(--success); }
.check-status[data-state="invalid"] { background: #fff0ee; color: var(--danger); }

.formula-note { margin-top: 20px; padding: 6px 22px; }
.formula-note summary { min-height: 48px; display: flex; align-items: center; cursor: pointer; color: var(--brand-dark); font-weight: 750; }
.formula-note summary::marker { color: var(--brand); }
.formula-note ul { margin: 2px 0 20px; padding-left: 22px; color: var(--muted); }
.formula-note li + li { margin-top: 7px; }

footer { padding: 28px 16px 36px; color: var(--muted); text-align: center; font-size: 0.88rem; }
footer p { margin: 0; }

@media (max-width: 760px) {
  .header-inner { min-height: 86px; }
  .brand img { width: 135px; }
  .header-label { font-size: 0.66rem; }
  .page-shell { padding-top: 48px; }
  .intro { margin-bottom: 28px; }
  .input-panel { grid-template-columns: 1fr; gap: 26px; padding: 28px 22px; }
  .results { margin-top: 48px; }
  .section-heading { align-items: center; }
  .summary-card { grid-template-columns: 1fr auto; padding: 24px 22px; }
  .summary-total { grid-column: 1 / -1; align-items: flex-start; padding: 20px 0 0; border-top: 1px solid var(--border); border-left: 0; text-align: left; }
  .operation-grid { grid-template-columns: 1fr; }
  .final-card { align-items: flex-start; flex-direction: column; padding: 26px 22px; }
}

@media (max-width: 420px) {
  .header-inner, .page-shell { width: min(calc(100% - 24px), var(--content)); }
  .header-label { display: none; }
  .section-heading { align-items: flex-start; flex-direction: column; gap: 8px; }
  .text-button { align-self: flex-end; }
  .summary-card { grid-template-columns: 1fr; gap: 8px; }
  .summary-card > .amount { text-align: left; }
  .operation-card header, dl { padding-left: 20px; padding-right: 20px; }
  dl > div { gap: 12px; }
}

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