:root {
  --ink: #14243a;
  --muted: #718091;
  --line: #dfe6e2;
  --canvas: #f1f3ef;
  --navy: #0e1a2c;
  --lime: #c9ef52;
  --coral: #ff735e;
  --shadow: 0 22px 60px rgba(18, 35, 56, .09);
  --sans: "Manrope", "Noto Sans SC", "Microsoft YaHei", "Segoe UI", sans-serif;
  --mono: "DM Mono", Consolas, monospace;
}

* { box-sizing: border-box; }
html { background: var(--canvas); }
body { min-width: 320px; margin: 0; color: var(--ink); background: var(--canvas); font-family: var(--sans); -webkit-font-smoothing: antialiased; }
a { color: inherit; text-decoration: none; }
button, input { font: inherit; }
.hidden { display: none !important; }
.billing-shell { min-height: 100vh; }
.billing-header { display: flex; width: min(1080px, calc(100% - 48px)); height: 84px; align-items: center; justify-content: space-between; margin: 0 auto; }
.billing-brand { display: inline-flex; align-items: center; gap: 10px; color: var(--navy); font-size: 18px; font-weight: 800; letter-spacing: .1em; }
.billing-brand img { width: 30px; height: 30px; border-radius: 8px; }
.billing-brand small { margin-left: 4px; color: #7c8a8f; font-size: 13px; font-weight: 500; letter-spacing: .02em; }
.back-link { color: #668c20; font-size: 13px; font-weight: 700; }
.billing-main { width: min(1080px, calc(100% - 48px)); margin: 0 auto; padding: 54px 0 80px; }
.billing-intro { max-width: 650px; }
.eyebrow { margin: 0; color: #87939b; font-family: var(--mono); font-size: 13px; letter-spacing: .1em; }
.billing-intro h1 { margin: 18px 0 13px; color: var(--ink); font-size: clamp(38px, 5vw, 62px); letter-spacing: -.08em; line-height: 1.1; }
.billing-intro > p:last-child { margin: 0; color: var(--muted); font-size: 15px; line-height: 1.8; }
.notice { margin-top: 34px; padding: 22px 24px; border: 1px solid var(--line); border-radius: 13px; background: rgba(255,255,255,.72); box-shadow: var(--shadow); }
.notice strong { color: var(--ink); font-size: 16px; }
.notice p { margin: 8px 0 16px; color: var(--muted); font-size: 13px; line-height: 1.7; }
.notice-info { border-color: #c9dca6; background: #f5f9e9; }
.notice-success { border-color: #afd686; background: #edf8db; }
.notice-error { border-color: #f0bbb1; background: #fff0ec; }
.button { display: inline-flex; min-height: 44px; align-items: center; justify-content: center; gap: 12px; padding: 0 18px; border: 1px solid transparent; border-radius: 8px; cursor: pointer; font-size: 13px; font-weight: 700; transition: transform .2s ease, box-shadow .2s ease, background .2s ease; }
.button:hover { transform: translateY(-1px); }
.button:disabled { cursor: wait; opacity: .6; transform: none; }
.button span { font-size: 17px; font-weight: 400; }
.button-primary { color: #20321b; background: var(--lime); box-shadow: 0 10px 22px rgba(131, 170, 33, .18); }
.button-secondary { color: var(--ink); border-color: #cfd9d5; background: #fff; }
.account-panel { margin-top: 34px; padding: 24px; border: 1px solid var(--line); border-radius: 14px; background: rgba(255,255,255,.76); box-shadow: var(--shadow); }
.section-label { display: flex; justify-content: space-between; gap: 20px; color: #7d8c91; font-family: var(--mono); font-size: 13px; letter-spacing: .06em; }
.section-label span:last-child { color: var(--ink); font-family: var(--sans); font-weight: 700; letter-spacing: 0; }
.account-summary { display: grid; grid-template-columns: repeat(4, 1fr); gap: 15px; margin-top: 21px; }
.account-summary > div { min-height: 110px; padding: 18px; border-radius: 10px; background: #f2f5f0; }
.metric-label, .metric-hint { margin: 0; color: #7d8c91; font-size: 13px; }
.account-summary strong { display: block; margin-top: 11px; color: var(--ink); font-size: 25px; letter-spacing: -.04em; }
.metric-hint { margin-top: 6px; }
.plan-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 17px; margin-top: 34px; }
.plan-card { display: flex; min-height: 370px; flex-direction: column; padding: 29px; border: 1px solid var(--line); border-radius: 14px; background: rgba(255,255,255,.75); box-shadow: var(--shadow); }
.plan-card-pro { border-color: #b5d96a; color: #eff5f2; background: var(--navy); }
.plan-card-head { display: flex; align-items: center; justify-content: space-between; gap: 15px; }
.plan-kicker { color: #89939b; font-family: var(--mono); font-size: 13px; letter-spacing: .1em; }
.plan-card-pro .plan-kicker { color: #a7b2bd; }
.plan-badge { padding: 5px 8px; border-radius: 5px; color: #66891c; background: #eef8d4; font-size: 13px; font-weight: 700; }
.plan-card-pro .plan-badge { color: #263b20; background: var(--lime); }
.plan-card h2 { margin: 44px 0 10px; font-size: 27px; letter-spacing: -.06em; }
.plan-card > p { min-height: 48px; margin: 0; color: #7d8c91; font-size: 14px; line-height: 1.75; }
.plan-card-pro > p { color: #abb8be; }
.plan-price { display: flex; align-items: baseline; gap: 9px; margin-top: 24px; }
.plan-price strong { color: var(--ink); font-size: 32px; letter-spacing: -.06em; }
.plan-card-pro .plan-price strong { color: var(--lime); }
.plan-price span { color: #7d8c91; font-size: 13px; }
.plan-card-pro .plan-price span { color: #abb8be; }
.plan-card ul { display: grid; gap: 9px; margin: 23px 0 0; padding: 0; color: #58697b; font-size: 13px; list-style: none; }
.plan-card-pro ul { color: #d2dbd8; }
.plan-card li::before { margin-right: 9px; color: #79a21c; content: "✓"; font-weight: 800; }
.checkout-panel { display: grid; grid-template-columns: 1fr minmax(280px, 390px); gap: 45px; align-items: center; margin-top: 34px; padding: 30px; border-radius: 14px; color: #eef4ef; background: #162942; box-shadow: var(--shadow); }
.checkout-panel h2 { margin: 14px 0 10px; color: #f1f5f3; font-size: 28px; letter-spacing: -.05em; }
.checkout-panel p { margin: 0; color: #aab7be; font-size: 14px; line-height: 1.75; }
.checkout-panel form { display: grid; gap: 9px; }
.checkout-panel label { color: #dce5e1; font-size: 13px; font-weight: 700; }
.checkout-panel input { width: 100%; min-height: 44px; padding: 0 12px; border: 1px solid rgba(226,239,234,.2); border-radius: 8px; outline: 0; color: #f2f6f4; background: rgba(255,255,255,.08); font-size: 13px; }
.checkout-panel input:focus { border-color: var(--lime); box-shadow: 0 0 0 3px rgba(201,239,82,.12); }
.checkout-panel input::placeholder { color: #8c9ba1; }
.checkout-panel .button { margin-top: 6px; }
.form-hint { color: #93a5aa !important; font-size: 13px !important; }
.billing-footnote { margin-top: 30px; color: #84908f; font-size: 13px; line-height: 1.7; }
.billing-footnote p { margin: 5px 0; }
.billing-footer { display: flex; width: min(1080px, calc(100% - 48px)); min-height: 80px; align-items: center; justify-content: space-between; gap: 20px; margin: 0 auto; border-top: 1px solid var(--line); color: #84908f; font-size: 13px; }

@media (max-width: 760px) {
  .account-summary { grid-template-columns: repeat(2, 1fr); }
  .checkout-panel { grid-template-columns: 1fr; gap: 25px; }
}

@media (max-width: 560px) {
  .billing-header, .billing-main, .billing-footer { width: calc(100% - 32px); }
  .billing-header { height: 72px; }
  .billing-main { padding-top: 35px; }
  .billing-intro h1 { font-size: 40px; }
  .plan-grid { grid-template-columns: 1fr; }
  .account-summary { gap: 10px; }
  .account-summary > div { padding: 14px; }
  .checkout-panel { padding: 23px; }
  .billing-footer { align-items: flex-start; flex-direction: column; padding: 22px 0; }
}