/* 全局样式定义 */
  html {
      scroll-behavior: smooth;
      font-size: 17px;
  }

  @media (max-width: 768px) {
    html {
      font-size: 15px; /* 你想更小就 14px */
    }
  }
  body {
      font-family: 'Noto Sans SC', sans-serif;
      background-color: #f8faff;
  }
  .gradient-text {
      background: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
  }
  .hero-gradient {
      background: radial-gradient(circle at top, rgba(99, 102, 241, 0.05) 0%, transparent 70%);
  }
  .card-shadow {
      box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.04), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
  }
  /* 避免导航栏遮挡锚点标题 */
  section {
      scroll-margin-top: 6rem;
  }
  /* 移动端菜单切换动画 */
  #mobile-menu {
      transition: all 0.3s ease-in-out;
  }
  .menu-hidden {
      transform: translateY(-20px);
      opacity: 0;
      pointer-events: none;
  }

  @font-face {
    font-family: "Noto Sans SC";
    font-style: normal;
    font-weight: 400;
    src: url("../fonts/noto-sans-sc-v40-chinese-simplified-regular.woff2") format("woff2");
  }
  
  @font-face {
    font-family: "Noto Sans SC";
    font-style: normal;
    font-weight: 500;
    src: url("../fonts/noto-sans-sc-v40-chinese-simplified-500.woff2") format("woff2");
  }
  
  @font-face {
    font-family: "Noto Sans SC";
    font-style: normal;
    font-weight: 700;
    src: url("../fonts/noto-sans-sc-v40-chinese-simplified-700.woff2") format("woff2");
  }

  .buy-modal {
    position: fixed;
    inset: 0;
    z-index: 60;
    background: rgba(15, 23, 42, 0.55);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
  }

  .modal-hidden {
    display: none;
  }

  .buy-modal__panel {
    width: min(680px, 100%);
    max-height: calc(100vh - 2rem);
    overflow-y: auto;
    background: #fff;
    border-radius: 1rem;
    padding: 1.25rem;
    box-shadow: 0 20px 40px rgba(2, 6, 23, 0.2);
    position: relative;
  }

  .buy-modal__close {
    position: absolute;
    top: 0.5rem;
    right: 0.75rem;
    font-size: 1.8rem;
    line-height: 1;
    color: #64748b;
    border: 0;
    background: transparent;
    cursor: pointer;
  }

  .buy-modal__close:hover {
    color: #1e293b;
  }

  .buy-modal__image-wrap,
  .buy-modal__guide-wrap {
    margin-top: 1rem;
    margin-bottom: 1rem;
    display: flex;
    justify-content: center;
  }

  .buy-modal__qr {
    width: min(200px, 100%);
    border-radius: 0.75rem;
    border: 1px solid #e2e8f0;
  }

  .buy-modal__guide {
    width: min(560px, 100%);
    border-radius: 0.75rem;
    border: 1px solid #e2e8f0;
  }

  .modal-steps-text {
    letter-spacing: 0.02em;
  }