/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; font-size: 16px; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
  color: #222;
  line-height: 1.6;
  background: #fff;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}
h1, h2, h3, h4, p, ul, ol { margin: 0; padding: 0; }
ul, ol { list-style: none; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; display: block; }
button { font: inherit; cursor: pointer; border: none; background: none; color: inherit; }
:focus-visible { outline: 2px solid #ff6b35; outline-offset: 2px; border-radius: 4px; }

/* ===== Variables ===== */
:root {
  --primary: #ff6b35;
  --primary-dark: #e65528;
  --secondary: #f73446;
  --gradient: linear-gradient(135deg, #ff6b35 0%, #f73446 100%);
  --dark: #1a1a2e;
  --text: #333;
  --muted: #666;
  --light: #f8f9fb;
  --border: #e8eaed;
  --shadow: 0 4px 20px rgba(0,0,0,0.08);
  --radius: 16px;
  --max-w: 1200px;
}

/* ===== Layout ===== */
.container { width: 92%; max-width: var(--max-w); margin: 0 auto; }
.section { padding: 64px 0; }
.alt-bg { background: var(--light); }
.section-head { text-align: center; margin-bottom: 42px; }
.section-head h2 { font-size: 2rem; color: var(--dark); margin-bottom: 10px; }
.section-head p { color: var(--muted); font-size: 1.05rem; }
.section-head.light h2, .section-head.light p { color: #fff; }

/* ===== Header / Nav ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.96);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.logo { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; font-size: 1.25rem; color: var(--dark); }
.logo-img { width: auto; height: 36px; display: block; }
.logo-text { font-size: 1.2rem; font-weight: 800; color: var(--dark); letter-spacing: .5px; }
.site-footer .logo-text { color: #fff; }
.nav-menu { display: flex; align-items: center; gap: 4px; }
.nav-menu a { display: block; padding: 8px 14px; border-radius: 8px; color: var(--text); font-weight: 500; transition: color .2s, background .2s; }
.nav-menu a:hover, .nav-menu a.active { color: var(--primary); background: #fff1eb; }
.nav-menu .btn-small { padding: 8px 18px; background: var(--gradient); color: #fff !important; }
.nav-menu .btn-small:hover { background: var(--gradient); color: #fff; transform: none; }
.nav-toggle { display: none; flex-direction: column; gap: 5px; padding: 8px; border-radius: 6px; }
.nav-toggle span { display: block; width: 24px; height: 2px; background: var(--dark); transition: transform .25s, opacity .25s; }
.nav-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.nav-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 14px 28px; border-radius: 50px; font-weight: 600;
  transition: transform .15s, box-shadow .15s; white-space: nowrap;
}
.btn:hover { transform: translateY(-2px); box-shadow: 0 8px 20px rgba(255,107,53,0.25); }
.btn-primary { background: var(--gradient); color: #fff; }
.btn-outline { border: 2px solid var(--primary); color: var(--primary); }
.btn-outline:hover { background: #fff1eb; }

/* ===== Hero ===== */
.hero { background: linear-gradient(135deg, #fff8f5 0%, #fff0ed 100%); padding: 72px 0 64px; overflow: hidden; }
.hero-inner { display: grid; grid-template-columns: 1.1fr 0.9fr; gap: 48px; align-items: center; }
.tag {
  display: inline-block; padding: 6px 14px; border-radius: 50px;
  background: #fff; color: var(--secondary); font-weight: 700; font-size: 0.875rem;
  border: 1px solid #ffd6d0; margin-bottom: 18px;
}
.hero h1 { font-size: 2.6rem; line-height: 1.2; color: var(--dark); margin-bottom: 18px; }
.hero-desc { font-size: 1.1rem; color: var(--muted); margin-bottom: 28px; max-width: 540px; }
.hero-desc strong { color: var(--text); }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 36px; }
.hero-badges { display: flex; gap: 28px; flex-wrap: wrap; }
.hero-badges li { display: flex; flex-direction: column; }
.hero-badges strong { font-size: 1.6rem; color: var(--primary); line-height: 1.1; }
.hero-badges span { font-size: 0.85rem; color: var(--muted); }

/* ===== Phone Mockup (Hero) ===== */
.hero-visual { display: flex; justify-content: center; }
.phone-mockup {
  width: 280px; height: 560px; position: relative;
  background: var(--dark); border-radius: 42px; padding: 14px;
  box-shadow: 0 24px 60px rgba(0,0,0,0.18);
}
.phone-notch {
  position: absolute; top: 12px; left: 50%; transform: translateX(-50%);
  width: 110px; height: 20px; background: var(--dark);
  border-radius: 0 0 16px 16px; z-index: 2;
}
.phone-screen {
  background: #fff; border-radius: 30px; height: 100%; padding: 38px 0 0;
  display: flex; flex-direction: column; gap: 12px; overflow: hidden;
}
.phone-screen .app-screen-img {
  width: 100%; height: 100%; object-fit: cover; display: block;
  border-radius: 0 0 30px 30px;
}
.phone-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 4px; }
.phone-title { font-weight: 800; color: var(--dark); font-size: 1.05rem; }
.phone-tag { font-size: 0.75rem; background: #fff1eb; color: var(--primary); padding: 4px 10px; border-radius: 6px; font-weight: 600; }
.phone-task {
  background: var(--light); border-radius: 12px; padding: 14px;
  display: flex; justify-content: space-between; align-items: center;
}
.phone-task.hot { background: #fff1eb; }
.phone-task-name { font-weight: 600; color: var(--text); font-size: 0.95rem; }
.phone-task-price { color: var(--secondary); font-weight: 800; font-size: 1.05rem; }
.phone-total {
  margin-top: auto; background: var(--gradient); color: #fff;
  border-radius: 14px; padding: 16px; display: flex; justify-content: space-between; align-items: center;
}
.phone-total strong { font-size: 1.4rem; }

/* ===== Steps ===== */
.steps-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.step-card {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px; position: relative; transition: transform .2s, box-shadow .2s;
}
.step-card:hover { box-shadow: var(--shadow); transform: translateY(-4px); }
.step-num {
  display: inline-block; font-size: 2.4rem; font-weight: 900;
  color: var(--primary); opacity: .18; line-height: 1;
  position: absolute; top: 18px; right: 22px;
}
.step-card h3 { font-size: 1.2rem; margin-bottom: 10px; color: var(--dark); }
.step-card p { color: var(--muted); font-size: 0.95rem; }

/* ===== Tasks ===== */
.task-tabs { display: flex; justify-content: center; gap: 10px; flex-wrap: wrap; margin-bottom: 32px; }
.tab {
  padding: 10px 22px; border-radius: 50px; background: #fff; border: 1px solid var(--border);
  color: var(--muted); font-weight: 500; transition: color .2s, border-color .2s, background .2s;
}
.tab:hover { border-color: var(--primary); color: var(--primary); }
.tab.active { background: var(--gradient); color: #fff; border-color: transparent; }
.task-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.task-card {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 22px; transition: transform .2s, box-shadow .2s;
}
.task-card:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
.task-card.hidden { display: none; }
.task-header { display: flex; justify-content: space-between; align-items: flex-start; gap: 12px; margin-bottom: 10px; }
.task-header h3 { font-size: 1.1rem; color: var(--dark); }
.task-price { color: var(--secondary); font-weight: 800; font-size: 1.25rem; white-space: nowrap; }
.task-desc { color: var(--muted); font-size: 0.92rem; margin-bottom: 16px; }
.task-meta { display: flex; justify-content: space-between; align-items: center; font-size: 0.85rem; color: var(--muted); }
.task-link { color: var(--primary); font-weight: 700; }
.task-link:hover { text-decoration: underline; }

/* ===== App Showcase Slider ===== */
.showcase-slider {
  display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center;
  max-width: 1100px; margin: 0 auto;
}
.slider-viewport { position: relative; overflow: hidden; border-radius: var(--radius); }
.slider-track { display: flex; transition: transform .5s ease; }
.slider-slide {
  min-width: 100%; padding: 12px 48px 48px;
  display: flex; flex-direction: column; align-items: center;
  box-sizing: border-box;
}
.slide-caption { margin-top: 22px; font-size: 1rem; color: var(--muted); text-align: center; }
.slider-arrow {
  position: absolute; top: calc(50% - 60px); transform: translateY(-50%);
  width: 44px; height: 44px; border-radius: 50%;
  background: rgba(255,255,255,0.92); color: var(--dark);
  font-size: 1.6rem; line-height: 1; display: grid; place-items: center;
  box-shadow: 0 4px 14px rgba(0,0,0,0.12); z-index: 2;
  transition: background .2s, color .2s;
}
.slider-arrow:hover { background: #fff; color: var(--primary); }
.slider-prev { left: 8px; }
.slider-next { right: 8px; }
.slider-dots {
  position: absolute; bottom: 14px; left: 50%; transform: translateX(-50%);
  display: flex; gap: 10px; z-index: 2;
}
.slider-dots .dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: #d8d8d8; transition: background .2s, width .2s, border-radius .2s;
}
.slider-dots .dot.active { background: var(--primary); width: 26px; border-radius: 5px; }

/* ===== Slide phone (mini) ===== */
.slide-phone {
  width: 220px; height: 440px; position: relative;
  background: var(--dark); border-radius: 32px; padding: 12px;
  box-shadow: 0 16px 40px rgba(0,0,0,0.14);
}
.slide-phone .phone-notch { width: 80px; height: 16px; top: 10px; }
.phone-screen.mini { padding: 30px 0 0; gap: 10px; border-radius: 22px; overflow: hidden; }
.phone-screen.mini .app-screen-img {
  width: 100%; height: 100%; object-fit: cover; display: block;
  border-radius: 0 0 22px 22px;
}
@media (max-width: 480px) {
  .phone-screen.mini { padding-top: 26px; }
}
.phone-screen.mini .phone-title { font-size: 0.95rem; }
.phone-screen.mini .phone-task { padding: 11px; }
.phone-screen.mini .phone-task-name { font-size: 0.85rem; }
.phone-screen.mini .phone-task-price { font-size: 0.95rem; }
.redpacket {
  background: linear-gradient(135deg, #ff6b35 0%, #f73446 100%); color: #fff;
  border-radius: 12px; padding: 16px; display: flex; flex-direction: column; gap: 2px;
}
.redpacket.sm { background: #fff1eb; color: var(--secondary); }
.redpacket-amt { font-size: 1.3rem; font-weight: 800; }
.redpacket.sm .redpacket-amt { font-size: 1rem; }
.redpacket-tip { font-size: 0.8rem; opacity: .9; }
.cash-item {
  background: var(--light); border-radius: 12px; padding: 12px;
  display: flex; justify-content: space-between; align-items: center;
}
.cash-name { font-size: 0.85rem; color: var(--text); }
.cash-amt { color: #389e0d; font-weight: 800; font-size: 0.95rem; }

/* ===== Showcase features ===== */
.showcase-features ol { counter-reset: feature; }
.showcase-features li {
  display: flex; flex-direction: column; gap: 4px;
  padding: 18px 0 18px 50px; position: relative; border-bottom: 1px dashed var(--border);
}
.showcase-features li:last-child { border-bottom: none; }
.showcase-features li::before {
  counter-increment: feature; content: counter(feature);
  position: absolute; left: 0; top: 18px;
  width: 32px; height: 32px; border-radius: 50%;
  background: var(--gradient); color: #fff;
  display: grid; place-items: center; font-weight: 700; font-size: 0.9rem;
}
.showcase-features strong { font-size: 1.1rem; color: var(--secondary); }
.showcase-features span { color: var(--muted); font-size: 0.95rem; }

/* ===== Testimonials ===== */
.testimonials { background: var(--dark); color: #fff; }
.review-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.review-card {
  background: rgba(255,255,255,0.06); border: 1px solid rgba(255,255,255,0.1);
  border-radius: var(--radius); padding: 26px;
}
.reviewer { display: flex; align-items: center; gap: 14px; margin-bottom: 16px; }
.avatar {
  width: 48px; height: 48px; border-radius: 50%;
  background: var(--gradient); display: grid; place-items: center;
  font-weight: 800; color: #fff; flex-shrink: 0;
}
.reviewer h3 { font-size: 1rem; }
.reviewer span { font-size: 0.85rem; color: #b0b3c7; }
.review-text { font-size: 0.95rem; color: #ddd; margin-bottom: 16px; }
.review-income { color: #ffb8a8; font-size: 0.9rem; }
.review-income strong { color: #fff; font-size: 1.1rem; margin-left: 4px; }
.platform-stats {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px;
  margin-top: 48px; text-align: center;
}
.platform-stats div { background: rgba(255,255,255,0.06); border-radius: var(--radius); padding: 24px; }
.platform-stats strong { display: block; font-size: 2rem; color: #fff; }
.platform-stats span { font-size: 0.9rem; color: #b0b3c7; }

/* ===== About highlights ===== */
.about-highlights { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.highlight {
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 24px; transition: transform .2s, box-shadow .2s;
}
.highlight:hover { box-shadow: var(--shadow); transform: translateY(-3px); }
.highlight-num { font-size: 1.8rem; font-weight: 900; color: var(--primary); opacity: .25; }
.highlight h3 { font-size: 1.1rem; color: var(--dark); margin: 6px 0 8px; }
.highlight p { color: var(--muted); font-size: 0.9rem; }

/* ===== Download ===== */
.download { background: linear-gradient(135deg, #fff8f5 0%, #fff0ed 100%); }
.download-inner { display: grid; grid-template-columns: 1.2fr 1fr; gap: 48px; align-items: center; }
.download h2 { font-size: 2rem; color: var(--dark); margin-bottom: 14px; }
.download p { color: var(--muted); margin-bottom: 20px; }
.download-benefits { margin-bottom: 28px; }
.download-benefits li {
  padding: 10px 0; padding-left: 28px; position: relative;
  border-bottom: 1px solid var(--border); color: var(--text);
}
.download-benefits li::before {
  content: "✓"; position: absolute; left: 0; color: var(--primary); font-weight: 800;
}
.download-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.download-qr { text-align: center; }
.qr-img {
  display: block; width: 180px; height: 180px; margin: 0 auto 14px;
  background: #fff; border: 1px solid var(--border); border-radius: var(--radius);
  padding: 12px; image-rendering: pixelated;
}
.qr-tip { font-size: 0.9rem; color: var(--muted); }

/* ===== FAQ ===== */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: #fff; border: 1px solid var(--border); border-radius: 12px;
  margin-bottom: 14px; overflow: hidden;
}
.faq-item summary {
  padding: 18px 22px; font-weight: 600; color: var(--dark);
  cursor: pointer; list-style: none; position: relative; padding-right: 44px;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+"; position: absolute; right: 22px; top: 50%; transform: translateY(-50%);
  font-size: 1.4rem; color: var(--primary); font-weight: 300; transition: transform .2s;
}
.faq-item[open] summary::after { content: "−"; }
.faq-body { padding: 0 22px 18px; color: var(--muted); font-size: 0.95rem; }
.faq-body strong { color: var(--text); }

/* ===== Footer ===== */
.site-footer { background: #111; color: #bbb; padding: 56px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 36px; margin-bottom: 40px; }
.footer-brand .logo { margin-bottom: 14px; }
.footer-brand .logo-img { height: 36px; }
.footer-desc { font-size: 0.9rem; color: #888; line-height: 1.7; }
.footer-grid h3 { color: #fff; font-size: 1rem; margin-bottom: 16px; }
.footer-grid ul li { margin-bottom: 10px; }
.footer-grid a { color: #aaa; transition: color .2s; }
.footer-grid a:hover { color: var(--primary); }
.footer-grid p { color: #888; font-size: 0.9rem; margin-bottom: 6px; }
.footer-bottom { border-top: 1px solid #222; padding-top: 24px; text-align: center; font-size: 0.85rem; color: #777; }
.footer-bottom p { margin-bottom: 6px; }

/* ===== Backtop ===== */
.backtop {
  position: fixed; right: 20px; bottom: 20px; z-index: 99;
  width: 44px; height: 44px; border-radius: 50%;
  background: var(--gradient); color: #fff;
  display: grid; place-items: center; font-size: 1.2rem;
  box-shadow: 0 4px 12px rgba(247,52,70,0.3);
  opacity: 0; pointer-events: none; transition: opacity .2s, transform .2s;
}
.backtop.visible { opacity: 1; pointer-events: auto; }
.backtop:hover { transform: translateY(-3px); }

/* ===== Responsive ===== */
@media (max-width: 992px) {
  .hero-inner, .download-inner, .showcase-slider { grid-template-columns: 1fr; }
  .hero-visual { order: -1; }
  .steps-grid, .task-grid, .review-grid, .about-highlights { grid-template-columns: repeat(2, 1fr); }
  .platform-stats { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
  .showcase-slider { gap: 36px; }
}

@media (max-width: 768px) {
  .nav-toggle { display: flex; }
  .nav-menu {
    position: absolute; top: 64px; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--border);
    flex-direction: column; align-items: stretch; gap: 0;
    padding: 0 4%; max-height: 0; overflow: hidden;
    transition: max-height .3s ease, padding .3s ease;
  }
  .nav-menu.open { max-height: 420px; padding: 12px 4%; }
  .nav-menu a { border-radius: 0; padding: 12px 0; border-bottom: 1px solid var(--border); }
  .nav-menu li:last-child a { border-bottom: none; }
  .nav-menu .btn-small { margin-top: 8px; border-radius: 50px; text-align: center; }
  .hero { padding: 48px 0; }
  .hero h1 { font-size: 1.9rem; }
  .hero-actions { flex-direction: column; }
  .hero-actions .btn { width: 100%; }
  .section { padding: 48px 0; }
  .section-head h2 { font-size: 1.6rem; }
  .steps-grid, .task-grid, .review-grid, .about-highlights { grid-template-columns: 1fr; }
  .platform-stats { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; gap: 28px; }
  .download-actions { flex-direction: column; }
  .download-actions .btn { width: 100%; }
  .phone-mockup { width: 240px; height: 480px; }
}

@media (max-width: 480px) {
  html { font-size: 15px; }
  .hero-badges { gap: 18px; }
  .hero-badges strong { font-size: 1.3rem; }
  .task-tabs { gap: 8px; }
  .tab { padding: 8px 14px; font-size: 0.9rem; }
  .phone-mockup { width: 220px; height: 440px; }
  .slide-phone { width: 200px; height: 400px; }
  .slider-slide { padding: 12px 36px 48px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

/* ===== Scroll fade-in (progressive enhancement) ===== */
.js .step-card,
.js .review-card,
.js .highlight,
.js .faq-item {
  opacity: 0;
  transform: translateY(16px);
  transition: opacity .5s ease, transform .5s ease;
}
.js .step-card.in,
.js .review-card.in,
.js .highlight.in,
.js .faq-item.in {
  opacity: 1;
  transform: none;
}