:root {
  --ink: #14161a;
  --paper: #ffffff;
  --muted: #6b7280;
  --rule: #e5e7eb;
  --accent: #c8102e;
  --font: -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

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

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

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--paper);
}

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

a:hover {
  color: var(--accent);
}

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

.wrap {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 24px;
}

/* —— Top bar —— */
.site-header {
  border-bottom: 1px solid var(--rule);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 56px;
}

.brand {
  font-weight: 600;
  font-size: 17px;
  text-decoration: none;
  color: var(--ink);
}

.nav {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav a {
  text-decoration: none;
  font-size: 15px;
  color: var(--ink);
}

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

/* —— Buttons —— */
.btn {
  display: inline-block;
  padding: 10px 16px;
  font-size: 15px;
  font-family: inherit;
  line-height: 1.2;
  text-decoration: none;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: var(--paper);
  color: var(--ink);
  cursor: pointer;
}

.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  color: #fff;
  filter: brightness(0.95);
}

.nav .btn-primary {
  padding: 8px 14px;
}

/* —— Hero —— */
.hero {
  padding: 40px 0 64px;
}

.hero-grid {
  display: grid;
  gap: 24px;
  align-items: start;
}

/* Mobile: H1 → calculator → supporting copy */
.hero-title {
  margin: 0;
  font-size: 30px;
  font-weight: 600;
  line-height: 1.15;
  order: 1;
}

.hero-grid .calc {
  order: 2;
}

.hero-copy {
  order: 3;
}

@media (min-width: 800px) {
  .hero-grid {
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    grid-template-areas:
      "title calc"
      "copy calc";
  }

  .hero-title {
    grid-area: title;
    order: unset;
    font-size: 48px;
    margin: 0 0 16px;
  }

  .hero-copy {
    grid-area: copy;
    order: unset;
  }

  .hero-grid .calc {
    grid-area: calc;
    order: unset;
  }
}

.hero-lede {
  margin: 0 0 16px;
  font-size: 20px;
  font-weight: 500;
  color: var(--ink);
}

.hero-body {
  margin: 0;
  color: var(--muted);
}

/* —— Calculator card —— */
.calc {
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 24px;
  display: grid;
  gap: 24px;
}

/* Mobile: result above inputs (DOM order). Desktop: reverse so inputs left / result right feels natural —
   SPEC: DOM 顺序为结果 → 输入，桌面用 grid 反转视觉顺序. */
.calc-result {
  order: 1;
}

.calc-form {
  order: 2;
}

@media (min-width: 800px) {
  .calc {
    grid-template-columns: 1fr 1fr;
    align-items: start;
  }

  .calc-result {
    order: 2;
  }

  .calc-form {
    order: 1;
  }
}

.field {
  margin-bottom: 16px;
}

.field:last-child {
  margin-bottom: 0;
}

.field label {
  display: block;
  font-size: 14px;
  margin-bottom: 6px;
  color: var(--ink);
}

.field input[type="number"],
.field select {
  width: 100%;
  padding: 8px 10px;
  font-size: 16px;
  font-family: var(--mono);
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: var(--paper);
  color: var(--ink);
}

.field-check {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-bottom: 16px;
}

.field-check input {
  margin-top: 4px;
}

.field-check label {
  font-size: 14px;
  line-height: 1.4;
}

.advanced {
  margin-top: 8px;
  border: none;
}

.advanced summary {
  cursor: pointer;
  font-size: 14px;
  color: var(--muted);
  margin-bottom: 12px;
}

.badge-estimate {
  display: block;
  margin-bottom: 16px;
  padding: 8px 12px;
  font-size: 13px;
  line-height: 1.4;
  color: var(--accent);
  border: 1px solid var(--accent);
  border-radius: 4px;
}

.badge-estimate[hidden] {
  display: none;
}

.take-rate {
  margin: 0;
  font-family: var(--mono);
  font-size: 40px;
  font-weight: 600;
  line-height: 1.1;
  color: var(--accent);
}

@media (min-width: 800px) {
  .take-rate {
    font-size: 56px;
  }
}

.take-label {
  margin: 4px 0 16px;
  font-size: 14px;
  color: var(--muted);
}

.net-line {
  margin: 0 0 24px;
  font-size: 20px;
  font-weight: 600;
}

.fee-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--mono);
  font-size: 14px;
}

.fee-table th,
.fee-table td {
  padding: 6px 0;
  border-bottom: 1px solid var(--rule);
  text-align: left;
  font-weight: 400;
}

.fee-table td:last-child,
.fee-table th:last-child {
  text-align: right;
}

.fee-table tbody tr[hidden] {
  display: none;
}

.fee-table .total th,
.fee-table .total td {
  border-bottom: none;
  padding-top: 12px;
  font-weight: 600;
}

.fee-note {
  margin: 16px 0 0;
  font-size: 12px;
  line-height: 1.5;
  color: var(--muted);
}

/* —— Why band —— */
.why {
  padding: 64px 0;
  border-top: 1px solid var(--rule);
}

.why h2 {
  margin: 0 0 40px;
  font-size: 28px;
  font-weight: 600;
  line-height: 1.2;
}

.why-grid {
  display: grid;
  gap: 24px;
}

@media (min-width: 800px) {
  .why-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
  }
}

.why-item h3 {
  margin: 0 0 8px;
  font-size: 17px;
  font-weight: 600;
}

.why-item p {
  margin: 0;
  font-size: 15px;
  color: var(--muted);
}

/* —— Pricing —— */
.pricing {
  padding: 64px 0;
  border-top: 1px solid var(--rule);
}

.pricing h2 {
  margin: 0 0 40px;
  font-size: 28px;
  font-weight: 600;
}

.price-grid {
  display: grid;
  gap: 16px;
}

@media (min-width: 800px) {
  .price-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.price-card {
  border: 1px solid var(--rule);
  border-radius: 4px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.price-card h3 {
  margin: 0;
  font-size: 17px;
  font-weight: 600;
}

.price-card .price {
  margin: 8px 0;
  font-family: var(--mono);
  font-size: 28px;
  font-weight: 600;
}

.price-card .price span {
  font-size: 14px;
  font-weight: 400;
  color: var(--muted);
  font-family: var(--font);
}

.price-card p {
  margin: 0;
  font-size: 14px;
  color: var(--muted);
  flex: 1;
}

.price-card .btn {
  margin-top: 16px;
  text-align: center;
}

.price-card.featured {
  border-color: var(--ink);
}

/* —— FAQ —— */
.faq {
  padding: 64px 0;
  border-top: 1px solid var(--rule);
}

.faq h2 {
  margin: 0 0 24px;
  font-size: 28px;
  font-weight: 600;
}

.faq details {
  border-bottom: 1px solid var(--rule);
  padding: 16px 0;
}

.faq summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 16px;
}

.faq details p {
  margin: 12px 0 0;
  font-size: 15px;
  color: var(--muted);
}

/* —— Footer —— */
.site-footer {
  border-top: 1px solid var(--rule);
  padding: 40px 0;
  font-size: 14px;
  color: var(--muted);
}

.site-footer .wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: center;
  justify-content: space-between;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: center;
}

.site-footer a {
  color: var(--muted);
  text-decoration: none;
}

.site-footer a:hover {
  color: var(--accent);
}

.footer-sep {
  color: var(--rule);
}

/* —— Legal pages —— */
.legal {
  padding: 40px 0 64px;
  max-width: 720px;
}

.legal h1 {
  margin: 0 0 8px;
  font-size: 32px;
  font-weight: 600;
}

.legal .updated {
  margin: 0 0 32px;
  font-size: 14px;
  color: var(--muted);
}

.legal h2 {
  margin: 32px 0 12px;
  font-size: 20px;
  font-weight: 600;
}

.legal p {
  margin: 0 0 16px;
}

.legal ul {
  margin: 0 0 16px;
  padding-left: 1.25em;
}

.legal li {
  margin-bottom: 8px;
}