:root {
    color-scheme: light;
    --green: #16a56a;
    --green-dark: #087a4b;
    --ink: #17352a;
    --muted: #64776f;
    --line: #d9e9e1;
    --paper: rgba(255, 255, 255, 0.92);
    font-family: "Microsoft YaHei UI", "PingFang SC", system-ui, -apple-system, sans-serif;
  }
  
  * { box-sizing: border-box; }
  
  body {
    min-height: 100vh;
    margin: 0;
    color: var(--ink);
    background:
      radial-gradient(circle at 14% 15%, rgba(71, 205, 143, 0.22), transparent 31rem),
      radial-gradient(circle at 85% 80%, rgba(254, 211, 118, 0.2), transparent 28rem),
      linear-gradient(145deg, #f5fcf8 0%, #eef8f3 52%, #fbf8ee 100%);
  }
  
  body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    opacity: 0.32;
    background-image: radial-gradient(#79b79b 0.75px, transparent 0.75px);
    background-size: 22px 22px;
    mask-image: linear-gradient(to bottom, black, transparent 78%);
  }
  
  .page-shell {
    width: min(1040px, calc(100% - 40px));
    min-height: calc(100vh - 58px);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1.06fr 0.94fr;
    align-items: center;
    gap: clamp(42px, 7vw, 92px);
    padding: 64px 0 36px;
  }
  
  .intro { padding-left: 8px; }
  
  .brand-mark {
    width: 58px;
    height: 58px;
    display: grid;
    place-items: center;
    margin-bottom: 26px;
    border-radius: 18px;
    background: linear-gradient(145deg, #29c986, #079358);
    box-shadow: 0 14px 28px rgba(8, 143, 84, 0.22);
  }
  
  .brand-mark svg { width: 37px; fill: white; }
  
  .eyebrow {
    margin: 0 0 13px;
    color: var(--green-dark);
    font-size: 14px;
    font-weight: 800;
    letter-spacing: 0.22em;
  }
  
  h1 {
    max-width: 520px;
    margin: 0;
    font-size: clamp(38px, 5vw, 62px);
    line-height: 1.12;
    letter-spacing: -0.04em;
  }
  
  .subtitle {
    margin: 23px 0 30px;
    color: var(--muted);
    font-size: clamp(17px, 2vw, 20px);
    line-height: 1.8;
  }
  
  .benefits {
    display: grid;
    gap: 15px;
    margin: 0 0 31px;
    padding: 0;
    list-style: none;
  }
  
  .benefits li {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 16px;
    font-weight: 650;
  }
  
  .benefits li::before {
    content: "";
    width: 7px;
    height: 7px;
    flex: 0 0 auto;
    border: 5px solid rgba(22, 165, 106, 0.16);
    border-radius: 50%;
    background: var(--green);
    background-clip: padding-box;
  }
  
  .privacy-note {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin: 0;
    color: #74867e;
    font-size: 13px;
  }
  
  .privacy-note span { color: var(--green); font-weight: 900; }
  
  .join-card {
    position: relative;
    padding: 30px 34px 31px;
    text-align: center;
    border: 1px solid rgba(255, 255, 255, 0.8);
    border-radius: 30px;
    background: var(--paper);
    box-shadow: 0 26px 70px rgba(31, 89, 64, 0.14), 0 2px 8px rgba(31, 89, 64, 0.06);
    backdrop-filter: blur(18px);
  }
  
  .card-heading {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 14px;
    padding: 7px 13px;
    color: var(--green-dark);
    border-radius: 999px;
    background: #ebfaf2;
    font-size: 12px;
    font-weight: 750;
  }
  
  .live-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--green);
    box-shadow: 0 0 0 5px rgba(22, 165, 106, 0.12);
  }
  
  h2 { margin: 0; font-size: 25px; letter-spacing: -0.02em; }
  
  .card-help { margin: 10px 0 21px; color: var(--muted); font-size: 14px; }
  .mobile-help { display: none; }
  
  .qr-frame {
    position: relative;
    display: block;
    width: min(100%, 292px);
    aspect-ratio: 1;
    margin: 0 auto;
    padding: 16px;
    border: 0;
    border-radius: 22px;
    background: white;
    box-shadow: inset 0 0 0 1px #e7eee9, 0 12px 30px rgba(44, 92, 70, 0.09);
    cursor: zoom-in;
  }
  
  .qr-frame img { display: block; width: 100%; height: 100%; object-fit: contain; }
  
  .corner { position: absolute; width: 24px; height: 24px; border-color: var(--green); border-style: solid; }
  .corner-tl { top: 7px; left: 7px; border-width: 3px 0 0 3px; border-radius: 8px 0 0; }
  .corner-tr { top: 7px; right: 7px; border-width: 3px 3px 0 0; border-radius: 0 8px 0 0; }
  .corner-bl { bottom: 7px; left: 7px; border-width: 0 0 3px 3px; border-radius: 0 0 0 8px; }
  .corner-br { right: 7px; bottom: 7px; border-width: 0 3px 3px 0; border-radius: 0 0 8px; }
  
  .qr-status { margin: 18px 0 13px; color: #84948d; font-size: 12px; }
  
  .save-button {
    display: none;
    padding: 12px 20px;
    color: white;
    border: 0;
    border-radius: 13px;
    background: var(--green);
    cursor: pointer;
    font-weight: 750;
    text-decoration: none;
  }
  
  .support { margin: 16px 0 0; color: #9aa8a1; font-size: 12px; }
  
  footer { height: 58px; color: #8a9a92; text-align: center; font-size: 12px; }
  
  .qr-dialog {
    width: min(90vw, 460px);
    padding: 28px;
    text-align: center;
    border: 0;
    border-radius: 24px;
    box-shadow: 0 24px 80px rgba(9, 49, 31, 0.3);
  }
  
  .qr-dialog::backdrop { background: rgba(4, 29, 18, 0.7); backdrop-filter: blur(5px); }
  .qr-dialog p { margin: 0 0 18px; font-weight: 750; }
  .qr-dialog img { width: 100%; border-radius: 12px; }
  .dialog-close { position: absolute; top: 8px; right: 12px; border: 0; background: transparent; color: #718078; font-size: 28px; cursor: pointer; }
  
  @media (max-width: 760px) {
    .page-shell {
      width: min(100% - 28px, 480px);
      min-height: auto;
      grid-template-columns: 1fr;
      gap: 30px;
      padding: 36px 0 24px;
    }
    .intro { padding: 0 6px; text-align: center; }
    .brand-mark { width: 51px; height: 51px; margin: 0 auto 19px; border-radius: 16px; }
    .eyebrow { margin-bottom: 9px; }
    h1 { font-size: clamp(33px, 10vw, 45px); }
    .subtitle { margin: 15px 0 22px; font-size: 16px; }
    .benefits { width: fit-content; margin: 0 auto 23px; text-align: left; }
    .privacy-note { font-size: 12px; }
    .join-card { padding: 26px 20px 27px; border-radius: 25px; }
    h2 { font-size: 23px; }
    .desktop-help { display: none; }
    .mobile-help { display: block; }
    .qr-frame { width: min(100%, 315px); }
    .save-button { display: inline-block; }
  }
  
  @media (prefers-reduced-motion: no-preference) {
    .join-card { animation: rise 560ms cubic-bezier(.2,.8,.2,1) both; }
    .intro { animation: rise 480ms 80ms cubic-bezier(.2,.8,.2,1) both; }
    @keyframes rise { from { opacity: 0; transform: translateY(14px); } }
  }