/* ==========================================================================
   爱屠龙 / AITULONG — 品牌样式
   叠加在 Bootstrap 5.3 之上。仅用 CSS 实现导航与动效，不依赖 Bootstrap JS，
   保证 Chrome / Firefox / Edge / 手机浏览器 / 微信 / QQ(X5) 全兼容。
   ========================================================================== */

/* ---------- 设计令牌 ---------- */
:root {
  /* 品牌色（取自 logo：圆形 A+龙 徽标，深蓝→亮蓝渐变） */
  --brand-deep:   #006699;   /* 深蓝，沉稳 */
  --brand:        #0099cc;   /* 主品牌蓝 */
  --brand-bright: #2a9dff;   /* 亮蓝，强调 */
  --brand-ink:    #07314a;   /* 品牌墨色，深色块用 */

  /* 中性 */
  --ink:          #16212c;   /* 正文 */
  --muted:        #586876;   /* 次要文字 */
  --surface:      #ffffff;
  --surface-soft: #f5f9fc;   /* 极浅蓝灰底 */
  --surface-tint: #eaf3fa;   /* 浅蓝底 */
  --line:         #e1e9f1;

  /* 微信绿（客服 CTA） */
  --wechat:       #07c160;
  --wechat-ink:   #058f48;

  /* 节奏 */
  --radius:       16px;
  --radius-sm:    10px;
  --radius-lg:    24px;
  --shadow-sm:    0 1px 2px rgba(16, 41, 64, .06), 0 2px 8px rgba(16, 41, 64, .05);
  --shadow:       0 6px 24px rgba(11, 49, 74, .10);
  --shadow-lg:    0 18px 50px rgba(11, 49, 74, .16);

  --ease:         cubic-bezier(.16, 1, .3, 1);
  --dur:          .28s;

  --maxw:          1140px;
  --section-y:     clamp(3.5rem, 3rem + 3vw, 6rem);

  /* 覆盖 Bootstrap 主色，让 .btn-primary 等天然是品牌蓝 */
  --bs-primary:        var(--brand-deep);
  --bs-primary-rgb:    0, 102, 153;
  --bs-link-color:        var(--brand-deep);
  --bs-link-hover-color:  var(--brand-bright);
  --bs-body-color:        var(--ink);
  --bs-body-bg:           var(--surface);
  --bs-body-font-family:  "Inter", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", Roboto, system-ui, -apple-system, sans-serif;
  --bs-heading-color:     var(--brand-ink);
}

/* ---------- 基础 ---------- */
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { font-feature-settings: "kern" 1; -webkit-font-smoothing: antialiased; }

a { color: var(--brand-deep); text-decoration: none; transition: color var(--dur) var(--ease); }
a:hover { color: var(--brand-bright); }

::selection { background: var(--brand); color: #fff; }

h1, h2, h3 { font-weight: 800; letter-spacing: -.01em; color: var(--brand-ink); }
h1 { font-size: clamp(2rem, 1.4rem + 2.6vw, 3.1rem); line-height: 1.12; }
h2 { font-size: clamp(1.6rem, 1.2rem + 1.5vw, 2.25rem); line-height: 1.18; }

.section { padding-block: var(--section-y); }
.section-soft { background: var(--surface-soft); }
.container, .container-fluid { max-width: var(--maxw); }

.eyebrow {
  display: inline-flex; align-items: center; gap: .5rem;
  font-size: .8rem; font-weight: 700; letter-spacing: .12em; text-transform: uppercase;
  color: var(--brand-deep);
  background: var(--surface-tint);
  padding: .35rem .8rem; border-radius: 999px;
}
.lead-muted { color: var(--muted); font-size: 1.05rem; }

.text-brand { color: var(--brand-deep) !important; }
.bg-soft { background: var(--surface-soft) !important; }
.bg-brand { background: linear-gradient(135deg, var(--brand-deep), var(--brand-bright)) !important; color: #fff; }

/* ---------- 按钮 ---------- */
.btn { font-weight: 600; border-radius: var(--radius-sm); padding: .62rem 1.25rem; transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease), background var(--dur) var(--ease); }
.btn:focus-visible { outline: 3px solid rgba(0, 153, 204, .4); outline-offset: 2px; }

.btn-brand {
  background: linear-gradient(135deg, var(--brand-deep), var(--brand)); color: #fff; border: none;
  box-shadow: 0 6px 18px rgba(0, 102, 153, .28);
}
.btn-brand:hover { color: #fff; transform: translateY(-2px); box-shadow: 0 12px 28px rgba(0, 102, 153, .36); }

.btn-wechat {
  background: var(--wechat); color: #fff; border: none;
  box-shadow: 0 6px 18px rgba(7, 193, 96, .26);
}
.btn-wechat:hover { color: #fff; background: var(--wechat-ink); transform: translateY(-2px); box-shadow: 0 12px 28px rgba(7, 193, 96, .34); }

.btn-outline-brand { border: 1.5px solid var(--brand-deep); color: var(--brand-deep); background: transparent; }
.btn-outline-brand:hover { background: var(--brand-deep); color: #fff; transform: translateY(-2px); }

/* ---------- 顶栏 / 导航（纯 CSS） ---------- */
.site-header {
  position: sticky; top: 0; z-index: 1030;
  background: rgba(255, 255, 255, .85);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.site-header .bar { display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding-block: .55rem; }
.navbar-brand { display: inline-flex; align-items: center; gap: .6rem; font-weight: 800; color: var(--brand-ink); }
.navbar-brand img { height: 46px; width: auto; }
.navbar-brand:hover { color: var(--brand-ink); }

.nav-toggle-input { position: absolute; width: 1px; height: 1px; opacity: 0; }
.nav-toggle-btn {
  display: none; width: 44px; height: 44px; border: 1px solid var(--line); border-radius: 10px;
  background: #fff; cursor: pointer; align-items: center; justify-content: center;
}
.nav-toggle-btn span,
.nav-toggle-btn span::before,
.nav-toggle-btn span::after { content: ""; display: block; width: 20px; height: 2px; background: var(--brand-ink); border-radius: 2px; position: relative; transition: transform var(--dur) var(--ease), opacity var(--dur) var(--ease); }
.nav-toggle-btn span::before { position: absolute; top: -6px; }
.nav-toggle-btn span::after  { position: absolute; top: 6px; }

.nav-menu { display: flex; align-items: center; gap: .35rem; }
.nav-menu a { color: var(--ink); font-weight: 600; padding: .5rem .8rem; border-radius: 8px; }
.nav-menu a:hover { color: var(--brand-deep); background: var(--surface-tint); }
.nav-menu a[aria-current="page"] { color: var(--brand-deep); }
.lang-switch { font-weight: 700; color: var(--brand-deep) !important; border: 1px solid var(--line); margin-left: .4rem; }
.lang-switch:hover { border-color: var(--brand-deep); background: var(--surface-tint) !important; }
.nav-cta { margin-left: .5rem; }

/* 移动端折叠（checkbox hack，无 JS） */
@media (max-width: 991.98px) {
  .nav-toggle-btn { display: inline-flex; }
  .nav-menu {
    position: absolute; left: 0; right: 0; top: 100%;
    flex-direction: column; align-items: stretch; gap: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
    max-height: 0; overflow: hidden;
    transition: max-height var(--dur) var(--ease);
  }
  .nav-menu a { padding: .85rem 1.1rem; border-radius: 0; border-bottom: 1px solid var(--line); }
  .nav-menu .lang-switch, .nav-menu .nav-cta { margin: .6rem 1.1rem; border-radius: 10px; }
  .nav-toggle-input:checked ~ .nav-menu { max-height: 80vh; }
  .nav-toggle-input:checked ~ .nav-toggle-btn span { background: transparent; }
  .nav-toggle-input:checked ~ .nav-toggle-btn span::before { transform: translateY(6px) rotate(45deg); }
  .nav-toggle-input:checked ~ .nav-toggle-btn span::after  { transform: translateY(-6px) rotate(-45deg); }
}

/* ---------- Hero ---------- */
.hero { position: relative; overflow: hidden; background: var(--surface-soft); }
.hero::before {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background:
    radial-gradient(620px 420px at 88% -8%, rgba(42, 157, 255, .20), transparent 60%),
    radial-gradient(520px 360px at 4% 8%, rgba(0, 153, 204, .16), transparent 60%);
}
/* 首页 hero：居中单列（hero-text 仅在首页位于 hero-grid 内，内页不受影响） */
.hero .hero-grid { position: relative; z-index: 1; max-width: 760px; margin-inline: auto; text-align: center; padding-block: clamp(2.6rem, 2rem + 2.5vw, 4.2rem); }
.hero .hero-grid .lead { margin-inline: auto; }
.hero .hero-grid .hero-cta,
.hero .hero-grid .trust-strip { justify-content: center; }
.hero h1 .accent { color: var(--brand); }
.hero p.lead { color: var(--muted); font-size: 1.15rem; max-width: 40ch; }
.hero-cta { display: flex; flex-wrap: wrap; gap: .75rem; }
.trust-strip { display: flex; flex-wrap: wrap; gap: .5rem .9rem; margin-top: 1.6rem; color: var(--muted); font-size: .92rem; }
.trust-strip b { color: var(--brand-ink); }

/* ---------- 卡片 ---------- */
.card-tile { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 1.6rem; height: 100%; transition: transform var(--dur) var(--ease), box-shadow var(--dur) var(--ease), border-color var(--dur) var(--ease); }
.card-tile:hover { transform: translateY(-4px); box-shadow: var(--shadow); border-color: rgba(0, 153, 204, .4); }
.card-tile .ico { width: 48px; height: 48px; border-radius: 12px; display: inline-flex; align-items: center; justify-content: center; font-size: 1.4rem; background: var(--surface-tint); color: var(--brand-deep); margin-bottom: 1rem; }
.card-tile h3 { font-size: 1.18rem; margin-bottom: .5rem; }
.card-tile p { color: var(--muted); margin-bottom: 0; }
.card-tile ul { color: var(--muted); padding-left: 1.1rem; margin-bottom: 0; }
.card-tile ul li { margin-bottom: .35rem; }

/* 编号特征块 */
.feature-num { display: inline-flex; align-items: center; justify-content: center; width: 34px; height: 34px; border-radius: 50%; background: var(--brand-deep); color: #fff; font-weight: 800; font-size: .95rem; flex: none; }

/* ---------- CTA 横幅（微信） ---------- */
.cta-band { background: linear-gradient(135deg, var(--brand-ink), var(--brand-deep) 55%, var(--brand-bright)); color: #fff; border-radius: var(--radius-lg); padding: clamp(2rem, 1.5rem + 2vw, 3.2rem); position: relative; overflow: hidden; }
.cta-band::after { content: ""; position: absolute; inset: 0; background: radial-gradient(420px 260px at 90% 10%, rgba(255,255,255,.14), transparent 60%); pointer-events: none; }
.cta-band h2 { color: #fff; }
.cta-band p { color: rgba(255,255,255,.85); }
.cta-band .wechat-id { font-size: 1.5rem; font-weight: 800; letter-spacing: .02em; }

/* ---------- 微信 / 二维码卡 ---------- */
.qr-card { display: flex; gap: 1.4rem; align-items: center; flex-wrap: wrap; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: 1.4rem; box-shadow: var(--shadow-sm); }
.qr-card .qr-img { width: 168px; height: auto; border-radius: 14px; flex: none; background: var(--surface-soft); }
.qr-card .wxid { font-size: 1.6rem; font-weight: 800; color: var(--brand-ink); }
.copy-btn { background: var(--surface-tint); border: 1px solid var(--line); color: var(--brand-deep); font-weight: 700; border-radius: 8px; padding: .35rem .7rem; cursor: pointer; transition: background var(--dur) var(--ease); }
.copy-btn:hover { background: var(--brand-deep); color: #fff; }
.copied-tip { color: var(--wechat-ink); font-weight: 700; opacity: 0; transition: opacity var(--dur) var(--ease); }
.copied-tip.show { opacity: 1; }

/* ---------- 流程步骤 ---------- */
.steps { counter-reset: step; }
.step { position: relative; padding-left: 3rem; }
.step::before { counter-increment: step; content: counter(step); position: absolute; left: 0; top: 0; width: 38px; height: 38px; border-radius: 50%; background: #fff; border: 2px solid var(--brand); color: var(--brand-deep); font-weight: 800; display: inline-flex; align-items: center; justify-content: center; }
.step:not(:last-child)::after { content: ""; position: absolute; left: 18px; top: 42px; bottom: -1.2rem; width: 2px; background: var(--line); }

/* ---------- 表单 ---------- */
.form-control, .form-select { border-radius: var(--radius-sm); border-color: var(--line); padding: .7rem .9rem; }
.form-control:focus, .form-select:focus { border-color: var(--brand); box-shadow: 0 0 0 .2rem rgba(0,153,204,.18); }
.form-label { font-weight: 600; color: var(--brand-ink); }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--brand-ink); color: rgba(255,255,255,.78); padding-block: 3rem 1.5rem; }
.site-footer a { color: rgba(255,255,255,.78); }
.site-footer a:hover { color: #fff; }
.site-footer h4 { color: #fff; font-size: 1rem; margin-bottom: 1rem; }
.site-footer .foot-brand img { height: 44px; }
.site-footer hr { border-color: rgba(255,255,255,.12); }
.site-footer .legal { color: rgba(255,255,255,.55); font-size: .88rem; }

/* ---------- 入场动效（CSS only，尊重 reduced-motion） ---------- */
@keyframes fadeUp { from { opacity: 0; transform: translateY(14px); } to { opacity: 1; transform: none; } }
.reveal { animation: fadeUp .7s var(--ease) both; }
.reveal.d1 { animation-delay: .08s; } .reveal.d2 { animation-delay: .16s; }
.reveal.d3 { animation-delay: .24s; } .reveal.d4 { animation-delay: .32s; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { animation: none !important; }
  *, *::before, *::after { transition-duration: .01ms !important; }
}

/* ---------- 移动端底部转化条（仅手机） ---------- */
@media (max-width: 991.98px) {
  body.has-mobile-cta { padding-bottom: 58px; }
  .mobile-cta-bar { position: fixed; left: 0; right: 0; bottom: 0; z-index: 1020; display: flex; }
  .mobile-cta-bar a { flex: 1; border-radius: 0; padding-block: .9rem; font-size: 1rem; }
}

/* ---------- 杂项 ---------- */
.divider-dot { color: var(--line); margin: 0 .4rem; }
.kbd { background: var(--surface-tint); border: 1px solid var(--line); border-radius: 6px; padding: .1rem .4rem; font-size: .85em; font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }