/* ============================================
   YouDuPay Design System v2 — Dark Tech
   Stripe/Linear 风格深色设计系统
   ============================================ */

:root {
  --bg: #07090f;
  --bg-2: #0a0e18;
  --panel: rgba(255, 255, 255, 0.03);
  --panel-hover: rgba(255, 255, 255, 0.055);
  --border: rgba(255, 255, 255, 0.08);
  --border-strong: rgba(255, 255, 255, 0.14);
  --text: #e8ecf4;
  --text-2: #9aa4b8;
  --text-3: #5d6678;
  --accent: #10b981;
  --accent-2: #22d3ee;
  --gradient: linear-gradient(135deg, #10b981, #22d3ee);
  --radius: 16px;
  --font: "Inter", -apple-system, "SF Pro Display", "Segoe UI", "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
  --mono: "SF Mono", "JetBrains Mono", Consolas, "Courier New", monospace;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

::selection { background: rgba(16, 185, 129, 0.35); }

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

.container { max-width: 1160px; margin: 0 auto; padding: 0 24px; }

/* ---------- 背景光效 ---------- */
.bg-fx { position: fixed; inset: 0; z-index: -1; overflow: hidden; pointer-events: none; }
.bg-fx::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255,255,255,0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.025) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 60% at 50% 0%, #000 30%, transparent 75%);
}
.orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(110px);
  opacity: 0.5;
}
.orb-1 { width: 560px; height: 560px; background: rgba(16,185,129,0.16); top: -220px; left: 12%; }
.orb-2 { width: 460px; height: 460px; background: rgba(34,211,238,0.10); top: 10%; right: -140px; }
.orb-3 { width: 520px; height: 520px; background: rgba(16,185,129,0.07); top: 120%; left: 30%; }

/* ---------- 导航 ---------- */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  background: rgba(7, 9, 15, 0.72);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 66px;
}
.logo {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.045em;
}
.logo-mark {
  display: flex;
  align-items: center;
}
.logo-mark img {
  width: 30px;
  height: 30px;
  display: block;
}
.nav-links { display: flex; gap: 30px; align-items: center; }
.nav-links a { color: var(--text-2); font-size: 14.5px; font-weight: 500; transition: color 0.2s; }
.nav-links a:hover { color: var(--text); }
.nav-right { display: flex; gap: 14px; align-items: center; }

.lang-toggle {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 13px;
  border: 1px solid var(--border);
  border-radius: 99px;
  color: var(--text-2);
  font-size: 13px;
  background: transparent;
  cursor: pointer;
  font-family: var(--font);
  transition: all 0.2s;
}
.lang-toggle:hover { color: var(--text); border-color: var(--border-strong); }

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: 12px;
  font-size: 14.5px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  font-family: var(--font);
  transition: all 0.2s;
  white-space: nowrap;
}
.btn-primary {
  background: var(--gradient);
  color: #04120c;
  box-shadow: 0 4px 24px rgba(16, 185, 129, 0.35);
}
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 6px 32px rgba(16, 185, 129, 0.5); }
.btn-ghost {
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
}
.btn-ghost:hover { background: var(--panel-hover); border-color: var(--border-strong); }
.btn-sm { padding: 8px 16px; font-size: 13.5px; border-radius: 10px; }

.nav-burger { display: none; background: none; border: none; color: var(--text); cursor: pointer; padding: 8px; }

/* ---------- Hero ---------- */
.hero { padding: 168px 0 90px; text-align: center; position: relative; }
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 16px;
  border: 1px solid rgba(16, 185, 129, 0.3);
  background: rgba(16, 185, 129, 0.08);
  border-radius: 99px;
  color: var(--accent);
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  margin-bottom: 28px;
}
.eyebrow .dot {
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--accent);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(16,185,129,0.6); }
  50% { box-shadow: 0 0 0 6px rgba(16,185,129,0); }
}
.hero h1 {
  font-size: clamp(40px, 7vw, 74px);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.06;
  margin-bottom: 26px;
}
.grad-text {
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero .sub {
  max-width: 640px;
  margin: 0 auto 38px;
  color: var(--text-2);
  font-size: 18.5px;
  line-height: 1.65;
}
.hero-cta { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

/* 统计条 */
.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  margin-top: 78px;
  text-align: center;
}
.stat { background: var(--bg-2); padding: 30px 16px; }
.stat b {
  display: block;
  font-size: 32px;
  font-weight: 800;
  letter-spacing: -0.02em;
  background: var(--gradient);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.stat span { color: var(--text-2); font-size: 13.5px; }

/* ---------- 区块通用 ---------- */
section.block { padding: 96px 0; }
.section-head { text-align: center; max-width: 640px; margin: 0 auto 60px; }
.section-head h2 {
  font-size: clamp(30px, 4.5vw, 44px);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 16px;
}
.section-head p { color: var(--text-2); font-size: 16.5px; }
.kicker {
  display: block;
  color: var(--accent);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 14px;
}

/* ---------- Bento 特性 ---------- */
.bento {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 18px;
}
.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  transition: all 0.25s;
  position: relative;
  overflow: hidden;
}
.card:hover { background: var(--panel-hover); border-color: var(--border-strong); transform: translateY(-3px); }
.card .icon {
  width: 46px; height: 46px;
  border-radius: 12px;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.25);
  display: grid;
  place-items: center;
  font-size: 21px;
  margin-bottom: 20px;
}
.card h3 { font-size: 18.5px; font-weight: 700; margin-bottom: 10px; letter-spacing: -0.01em; }
.card p { color: var(--text-2); font-size: 14.5px; line-height: 1.7; }
.span-3 { grid-column: span 3; }
.span-2 { grid-column: span 2; }
.span-4 { grid-column: span 4; }

.card.feature-lg { display: flex; flex-direction: column; justify-content: space-between; }
.mini-stats { display: flex; gap: 22px; margin-top: 24px; }
.mini-stats div b { display: block; font-size: 22px; font-weight: 800; color: var(--accent); }
.mini-stats div span { font-size: 12.5px; color: var(--text-2); }

/* ---------- 解决方案 ---------- */
.sol-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 18px; }
.sol {
  display: flex;
  gap: 20px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  transition: all 0.25s;
}
.sol:hover { background: var(--panel-hover); border-color: rgba(16,185,129,0.35); }
.sol .icon {
  flex: 0 0 44px;
  width: 44px; height: 44px;
  border-radius: 11px;
  background: rgba(34, 211, 238, 0.1);
  border: 1px solid rgba(34, 211, 238, 0.22);
  display: grid;
  place-items: center;
  font-size: 20px;
}
.sol h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.sol p { color: var(--text-2); font-size: 14px; line-height: 1.7; }

/* ---------- 定价 ---------- */
.pricing { display: grid; grid-template-columns: repeat(2, minmax(0, 460px)); gap: 22px; justify-content: center; }
.price-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 38px 34px;
  position: relative;
  transition: all 0.25s;
}
.price-card:hover { transform: translateY(-3px); }
.price-card.hot {
  border-color: rgba(16, 185, 129, 0.45);
  background: linear-gradient(180deg, rgba(16,185,129,0.07), rgba(255,255,255,0.02));
  box-shadow: 0 20px 60px rgba(16, 185, 129, 0.12);
}
.plan-tag {
  position: absolute;
  top: -13px; left: 50%;
  transform: translateX(-50%);
  background: var(--gradient);
  color: #04120c;
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.08em;
  padding: 5px 16px;
  border-radius: 99px;
  text-transform: uppercase;
}
.plan-name { color: var(--text-2); font-size: 14px; font-weight: 600; margin-bottom: 14px; }
.price { display: flex; align-items: baseline; gap: 8px; margin-bottom: 26px; }
.price b { font-size: 46px; font-weight: 800; letter-spacing: -0.03em; }
.price span { color: var(--text-2); font-size: 14px; }
.price-card ul { list-style: none; margin-bottom: 30px; }
.price-card li {
  padding: 9px 0 9px 28px;
  position: relative;
  color: var(--text-2);
  font-size: 14.5px;
  border-bottom: 1px solid rgba(255,255,255,0.04);
}
.price-card li::before {
  content: "✓";
  position: absolute;
  left: 2px;
  color: var(--accent);
  font-weight: 800;
}
.price-card .btn { width: 100%; justify-content: center; }

/* ---------- 开发者 ---------- */
.dev { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; align-items: center; }
.dev ul { list-style: none; margin-top: 26px; }
.dev li { padding: 10px 0 10px 30px; position: relative; color: var(--text-2); font-size: 15px; }
.dev li::before {
  content: "→";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-weight: 700;
}
.code-window {
  background: #0d1117;
  border: 1px solid var(--border-strong);
  border-radius: 14px;
  overflow: hidden;
  box-shadow: 0 24px 80px rgba(0,0,0,0.5);
}
.code-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  background: rgba(255,255,255,0.02);
}
.code-bar i { width: 11px; height: 11px; border-radius: 50%; display: block; }
.code-bar .r { background: #ff5f57; } .code-bar .y { background: #febc2e; } .code-bar .g { background: #28c840; }
.code-bar span { margin-left: 8px; color: var(--text-3, #5d6678); font-size: 12.5px; font-family: var(--mono); }
.code-window pre {
  padding: 22px;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.75;
  color: #c9d1d9;
  overflow-x: auto;
}
.tk-c { color: #8b949e; } .tk-k { color: #79c0ff; } .tk-s { color: #a5d6ff; } .tk-n { color: #7ee787; } .tk-p { color: #ffa657; }

/* ---------- CTA 横幅 ---------- */
.cta-banner {
  text-align: center;
  border: 1px solid rgba(16, 185, 129, 0.3);
  background:
    radial-gradient(ellipse 60% 100% at 50% 0%, rgba(16,185,129,0.14), transparent),
    var(--panel);
  border-radius: 24px;
  padding: 72px 32px;
}
.cta-banner h2 { font-size: clamp(28px, 4vw, 40px); font-weight: 800; letter-spacing: -0.03em; margin-bottom: 14px; }
.cta-banner p { color: var(--text-2); margin-bottom: 32px; font-size: 16px; }

/* ---------- 页脚 ---------- */
footer { border-top: 1px solid var(--border); padding: 56px 0 40px; margin-top: 40px; }
.foot-grid {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 40px;
  flex-wrap: wrap;
  margin-bottom: 36px;
}
.foot-brand p { color: var(--text-2); font-size: 13.5px; margin-top: 14px; max-width: 320px; }
.foot-col b { display: block; font-size: 13px; text-transform: uppercase; letter-spacing: 0.1em; color: var(--text); margin-bottom: 16px; }
.foot-col a { display: block; color: var(--text-2); font-size: 14px; padding: 5px 0; transition: color 0.2s; }
.foot-col a:hover { color: var(--accent); }
.foot-bottom {
  border-top: 1px solid var(--border);
  padding-top: 26px;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  color: var(--text-2, #9aa4b8);
  font-size: 13px;
}

/* ---------- 内页（联系/法律） ---------- */
.page-hero { padding: 150px 0 40px; text-align: center; }
.page-hero h1 { font-size: clamp(32px, 5vw, 50px); font-weight: 800; letter-spacing: -0.03em; margin-bottom: 14px; }
.page-hero p { color: var(--text-2); max-width: 560px; margin: 0 auto; font-size: 16px; }

.contact-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin: 48px 0; }
.copy-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px;
  text-align: center;
  transition: all 0.25s;
}
.copy-card:hover { background: var(--panel-hover); border-color: rgba(16,185,129,0.35); }
.copy-card .icon { font-size: 30px; margin-bottom: 16px; }
.copy-card h3 { font-size: 15px; font-weight: 700; margin-bottom: 6px; }
.copy-card .desc { color: var(--text-2); font-size: 13px; margin-bottom: 18px; min-height: 40px; }
.copy-card .val {
  font-family: var(--mono);
  font-size: 15px;
  color: var(--accent);
  display: block;
  margin-bottom: 16px;
  word-break: break-all;
}
.perk {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--panel);
  padding: 30px;
  color: var(--text-2);
  font-size: 15px;
  line-height: 1.8;
  text-align: center;
}
.perk b { color: var(--text); }

.doc { max-width: 780px; margin: 0 auto; }
.doc .updated { color: var(--text-2); font-size: 13.5px; margin-bottom: 40px; }
.doc h2 {
  font-size: 21px;
  font-weight: 700;
  margin: 40px 0 14px;
  letter-spacing: -0.01em;
  padding-left: 14px;
  border-left: 3px solid var(--accent);
}
.doc p, .doc li { color: var(--text-2); font-size: 15px; line-height: 1.85; margin-bottom: 12px; }
.doc .lead { color: var(--text); font-size: 16px; }

/* ---------- 滚动动效 ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.in { opacity: 1; transform: none; }
.d1 { transition-delay: 0.08s; } .d2 { transition-delay: 0.16s; } .d3 { transition-delay: 0.24s; }

/* ---------- 响应式 ---------- */
@media (max-width: 900px) {
  .nav-links { display: none; }
  .nav-burger { display: block; }
  .nav-links.open {
    display: flex;
    position: absolute;
    top: 66px; left: 0; right: 0;
    flex-direction: column;
    background: rgba(7,9,15,0.97);
    border-bottom: 1px solid var(--border);
    padding: 22px 24px;
    gap: 18px;
  }
  .hero { padding-top: 130px; }
  .stats { grid-template-columns: repeat(2, 1fr); }
  .bento { grid-template-columns: 1fr; }
  .span-3, .span-2, .span-4 { grid-column: span 1; }
  .sol-list, .pricing, .dev, .contact-grid { grid-template-columns: 1fr; }
}

/* ---------- Hero animations ---------- */
.fade-up { opacity: 0; transform: translateY(22px); animation: fadeUpIn .85s cubic-bezier(.2,.7,.3,1) forwards; }
.d1 { animation-delay: .12s; }
.d2 { animation-delay: .24s; }
.d3 { animation-delay: .36s; }
@keyframes fadeUpIn { to { opacity: 1; transform: none; } }

/* 光晕呼吸 */
.hero::before {
  content: ""; position: absolute; z-index: -1;
  top: -180px; left: 50%; width: 780px; height: 560px;
  transform: translateX(-50%);
  background: radial-gradient(closest-side, rgba(16,185,129,.20), transparent 70%);
  filter: blur(28px);
  animation: auraDrift 14s ease-in-out infinite alternate;
  pointer-events: none;
}
@keyframes auraDrift {
  0%   { transform: translateX(-50%) translateY(0) scale(1); opacity: .85; }
  100% { transform: translateX(-50%) translateY(34px) scale(1.12); opacity: 1; }
}

/* 支付流水卡片 */
.flow-strip {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px;
  max-width: 880px; margin: 34px auto 0; text-align: left;
}
.flow-card {
  display: flex; align-items: center; gap: 12px;
  padding: 14px 16px;
  background: rgba(255,255,255,.035);
  border: 1px solid var(--border);
  border-radius: 14px;
  backdrop-filter: blur(8px);
  opacity: 0; transform: translateY(18px);
  animation: flowIn .7s cubic-bezier(.2,.7,.3,1) forwards;
}
.flow-strip.in .flow-card:nth-child(1) { animation-delay: .05s; }
.flow-strip.in .flow-card:nth-child(2) { animation-delay: .18s; }
.flow-strip.in .flow-card:nth-child(3) { animation-delay: .31s; }
@keyframes flowIn { to { opacity: 1; transform: none; } }
.flow-ico {
  flex: none; width: 32px; height: 32px; border-radius: 9px;
  display: grid; place-items: center; font-size: 14px;
  background: rgba(16,185,129,.14); color: var(--accent);
}
.flow-ico.route { background: rgba(96,165,250,.14); color: #60a5fa; }
.flow-ico.shield { background: rgba(251,191,36,.14); color: #fbbf24; }
.flow-meta { min-width: 0; }
.flow-meta b { display: block; font-size: 13.5px; font-weight: 700; letter-spacing: -.01em; }
.flow-meta span { font-size: 12px; color: var(--text-2); }
.flow-time {
  margin-left: auto; flex: none; font-size: 11.5px; font-weight: 700;
  color: var(--accent); font-variant-numeric: tabular-nums;
}

/* 进度条流动 */
.flow-bar {
  max-width: 880px; margin: 16px auto 0; height: 3px;
  background: rgba(255,255,255,.06); border-radius: 99px; overflow: hidden;
}
.flow-bar i {
  display: block; height: 100%; width: 30%; border-radius: 99px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
  animation: flowSlide 2.6s ease-in-out infinite;
}
@keyframes flowSlide {
  0%   { transform: translateX(-120%); }
  100% { transform: translateX(420%); }
}
.flow-bar.reveal { opacity: 0; transition: opacity .6s ease .5s; }
.flow-bar.reveal.in { opacity: 1; }

@media (max-width: 760px) {
  .flow-strip { grid-template-columns: 1fr; gap: 10px; }
}

@media (prefers-reduced-motion: reduce) {
  .fade-up, .flow-card, .flow-bar.reveal { animation: none !important; opacity: 1 !important; transform: none !important; transition: none !important; }
  .hero::before { animation: none; }
  .flow-bar i { animation: none; width: 100%; background: var(--accent); opacity: .5; }
}