/* ==========================================================================
   双成果业 · 官网样式
   ========================================================================== */

:root {
  --green-950: #14261a;
  --green-900: #1b3b1f;
  --green-800: #245129;
  --green-700: #2e7d32;
  --green-600: #3f9d46;
  --green-500: #4caf50;
  --green-100: #e8f5e9;
  --green-50: #f3f9f3;
  --amber: #e8a33d;
  --amber-deep: #d98c1f;
  --cream: #faf7ef;
  --ink: #1e3320;
  --muted: #67756a;
  --white: #ffffff;
  --line: rgba(30, 51, 32, 0.08);

  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", "Helvetica Neue",
    Arial, sans-serif;

  --shadow-sm: 0 2px 12px rgba(20, 38, 26, 0.06);
  --shadow-md: 0 12px 32px rgba(20, 38, 26, 0.10);
  --shadow-lg: 0 24px 60px rgba(20, 38, 26, 0.16);
  --radius: 18px;
  --radius-lg: 26px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font);
  color: var(--ink);
  background: var(--white);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
  text-decoration: none;
}

.container {
  width: 100%;
  max-width: 1160px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ==========================================================================
   顶部导航
   ========================================================================== */

.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 100;
  transition: background 0.3s ease, box-shadow 0.3s ease, padding 0.3s ease;
  padding: 18px 0;
}

.site-header.scrolled {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(14px);
  -webkit-backdrop-filter: saturate(180%) blur(14px);
  box-shadow: var(--shadow-sm);
  padding: 10px 0;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--white);
  transition: color 0.3s ease;
}

.site-header.scrolled .brand,
.site-header.scrolled .nav-link {
  color: var(--ink);
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--green-500), var(--green-700));
  color: #fff;
  box-shadow: 0 6px 16px rgba(76, 175, 80, 0.35);
}

.brand-text {
  font-size: 21px;
  font-weight: 700;
  letter-spacing: 1px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 30px;
}

.nav-link {
  position: relative;
  font-size: 15px;
  color: rgba(255, 255, 255, 0.9);
  transition: color 0.25s ease;
  padding: 4px 0;
}

.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 2px;
  background: currentColor;
  transition: width 0.25s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.btn-login {
  white-space: nowrap;
}

/* ==========================================================================
   按钮
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 600;
  border-radius: 999px;
  padding: 11px 26px;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease,
    color 0.2s ease, border-color 0.2s ease;
}

.btn:active {
  transform: translateY(1px);
}

.btn-login {
  background: transparent;
  border-color: rgba(255, 255, 255, 0.7);
  color: var(--white);
  padding: 8px 22px;
  font-size: 14px;
}

.btn-login:hover {
  background: var(--white);
  color: var(--green-700);
}

.site-header.scrolled .btn-login {
  background: var(--green-700);
  border-color: var(--green-700);
  color: var(--white);
}

.site-header.scrolled .btn-login:hover {
  background: var(--green-800);
  box-shadow: 0 6px 18px rgba(46, 125, 50, 0.3);
}

.btn-primary {
  background: linear-gradient(135deg, var(--green-500), var(--green-700));
  color: #fff;
  box-shadow: 0 10px 26px rgba(46, 125, 50, 0.35);
  padding: 14px 34px;
  font-size: 16px;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 34px rgba(46, 125, 50, 0.42);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.7);
  color: #fff;
  backdrop-filter: blur(4px);
  padding: 14px 34px;
  font-size: 16px;
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.22);
}

.btn-light {
  background: var(--white);
  color: var(--green-800);
  padding: 14px 34px;
  font-size: 16px;
}

.btn-light:hover {
  transform: translateY(-2px);
  box-shadow: 0 16px 34px rgba(0, 0, 0, 0.2);
}

/* ==========================================================================
   移动端菜单按钮
   ========================================================================== */

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  padding: 10px;
  background: transparent;
  border: none;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--white);
  border-radius: 2px;
  transition: background 0.3s ease, transform 0.3s ease, opacity 0.3s ease;
}

.site-header.scrolled .nav-toggle span {
  background: var(--ink);
}

.nav-toggle.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.open span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ==========================================================================
   Hero
   ========================================================================== */

.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  overflow: hidden;
  color: #fff;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background-image: url("../images/hero-bg.jpg");
  background-size: cover;
  background-position: center;
  transform: scale(1.05);
  animation: heroZoom 18s ease-out forwards;
}

@keyframes heroZoom {
  from { transform: scale(1.12); }
  to { transform: scale(1.05); }
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(20, 38, 26, 0.55) 0%,
    rgba(20, 38, 26, 0.35) 45%,
    rgba(20, 38, 26, 0.65) 100%
  );
}

.hero-content {
  position: relative;
  z-index: 2;
  padding-top: 90px;
  padding-bottom: 60px;
  animation: fadeUp 1s ease both;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

.hero-eyebrow {
  display: inline-block;
  font-size: 15px;
  letter-spacing: 6px;
  padding: 8px 22px;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: 999px;
  margin-bottom: 28px;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(4px);
}

.hero-title {
  font-size: clamp(52px, 9vw, 92px);
  font-weight: 800;
  letter-spacing: 8px;
  line-height: 1.1;
  margin-bottom: 22px;
  text-shadow: 0 6px 30px rgba(0, 0, 0, 0.3);
}

.hero-subtitle {
  font-size: clamp(16px, 2.4vw, 20px);
  color: rgba(255, 255, 255, 0.92);
  letter-spacing: 1px;
  margin-bottom: 42px;
}

.hero-actions {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.scroll-hint {
  position: absolute;
  left: 50%;
  bottom: 32px;
  transform: translateX(-50%);
  width: 26px;
  height: 42px;
  border: 2px solid rgba(255, 255, 255, 0.6);
  border-radius: 14px;
  z-index: 2;
}

.scroll-hint-dot {
  position: absolute;
  left: 50%;
  top: 8px;
  width: 4px;
  height: 8px;
  margin-left: -2px;
  border-radius: 4px;
  background: #fff;
  animation: scrollDot 1.8s ease-in-out infinite;
}

@keyframes scrollDot {
  0% { opacity: 0; transform: translateY(0); }
  40% { opacity: 1; }
  80% { opacity: 0; transform: translateY(14px); }
  100% { opacity: 0; }
}

/* ==========================================================================
   通用 Section
   ========================================================================== */

.section {
  padding: 96px 0;
}

.section-head {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 60px;
}

.section-eyebrow {
  display: inline-block;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 4px;
  color: var(--green-600);
  margin-bottom: 16px;
}

.section-title {
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 700;
  color: var(--green-950);
  letter-spacing: 1px;
  margin-bottom: 16px;
}

.section-lead {
  font-size: 16px;
  color: var(--muted);
}

/* ==========================================================================
   关于双成
   ========================================================================== */

.about {
  background: var(--green-50);
}

.about-grid {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 56px;
  align-items: center;
}

.about-text p {
  color: var(--muted);
  font-size: 16px;
  margin-bottom: 16px;
}

.about-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.stat {
  background: var(--white);
  border-radius: var(--radius);
  padding: 30px 16px;
  text-align: center;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--line);
}

.stat-num {
  font-size: 34px;
  font-weight: 800;
  color: var(--green-700);
  line-height: 1;
}

.stat-suffix {
  font-size: 18px;
  font-weight: 700;
  color: var(--green-700);
}

.stat-label {
  display: block;
  margin-top: 8px;
  font-size: 13px;
  color: var(--muted);
  letter-spacing: 1px;
}

/* ==========================================================================
   成长历程
   ========================================================================== */

.growth-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

.growth-card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--line);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.growth-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.growth-media {
  position: relative;
  height: 360px;
  overflow: hidden;
}

.growth-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.6s ease;
}

.growth-card:hover .growth-media img {
  transform: scale(1.05);
}

.growth-stage {
  position: absolute;
  left: 20px;
  bottom: 20px;
  padding: 6px 16px;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 2px;
  color: #fff;
  background: rgba(20, 38, 26, 0.55);
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: 999px;
  backdrop-filter: blur(6px);
}

.growth-body {
  padding: 28px 30px 32px;
}

.growth-body h3 {
  font-size: 22px;
  font-weight: 700;
  color: var(--green-900);
  margin-bottom: 10px;
}

.growth-body p {
  color: var(--muted);
  font-size: 15px;
}

/* ==========================================================================
   核心优势
   ========================================================================== */

.advantages-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.advantage {
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 36px 28px;
  text-align: center;
  transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.advantage:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-md);
  border-color: rgba(76, 175, 80, 0.3);
}

.advantage-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 16px;
  background: var(--green-100);
  color: var(--green-700);
}

.advantage h3 {
  font-size: 19px;
  font-weight: 700;
  color: var(--green-900);
  margin-bottom: 10px;
}

.advantage p {
  font-size: 14px;
  color: var(--muted);
}

/* ==========================================================================
   认养流程
   ========================================================================== */

.process {
  background: var(--cream);
}

.process-steps {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  counter-reset: step;
}

.step {
  position: relative;
  padding: 34px 26px;
  background: var(--white);
  border-radius: var(--radius);
  border: 1px solid var(--line);
  text-align: center;
}

.step-num {
  font-size: 30px;
  font-weight: 800;
  color: var(--amber);
  letter-spacing: 1px;
  margin-bottom: 12px;
}

.step h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--green-900);
  margin-bottom: 8px;
}

.step p {
  font-size: 14px;
  color: var(--muted);
}

/* ==========================================================================
   CTA
   ========================================================================== */

.cta {
  position: relative;
  background:
    linear-gradient(135deg, rgba(27, 59, 31, 0.94), rgba(46, 125, 50, 0.92)),
    url("../images/hero-bg.jpg") center/cover no-repeat;
  color: #fff;
  text-align: center;
  padding: 88px 0;
}

.cta-inner h2 {
  font-size: clamp(26px, 4vw, 36px);
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 14px;
}

.cta-inner p {
  font-size: 16px;
  color: rgba(255, 255, 255, 0.85);
  margin-bottom: 32px;
}

/* ==========================================================================
   页脚
   ========================================================================== */

.site-footer {
  background: var(--green-950);
  color: rgba(255, 255, 255, 0.72);
  padding-top: 60px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 40px;
  padding-bottom: 40px;
}

.footer-logo {
  font-size: 22px;
  font-weight: 700;
  color: #fff;
  letter-spacing: 1px;
}

.footer-tagline {
  margin-top: 8px;
  font-size: 14px;
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-links a,
.footer-contact p {
  font-size: 14px;
  transition: color 0.2s ease;
}

.footer-links a:hover {
  color: #fff;
}

.footer-contact p {
  margin-bottom: 8px;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  padding: 20px 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 13px;
}

.footer-bottom a:hover {
  color: #fff;
}

/* ==========================================================================
   滚动入场动画
   ========================================================================== */

.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
  .hero-bg { animation: none; transform: scale(1.05); }
}

/* ==========================================================================
   响应式
   ========================================================================== */

@media (max-width: 960px) {
  .main-nav {
    position: fixed;
    top: 0;
    right: 0;
    height: 100vh;
    width: min(320px, 82vw);
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    gap: 26px;
    padding: 40px;
    background: var(--green-950);
    transform: translateX(100%);
    transition: transform 0.35s ease;
  }

  .main-nav.open {
    transform: translateX(0);
  }

  .main-nav .nav-link {
    color: #fff;
    font-size: 18px;
  }

  .nav-toggle {
    display: flex;
  }

  .about-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .advantages-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .process-steps {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 28px;
  }
}

@media (max-width: 560px) {
  .section { padding: 72px 0; }

  .growth-grid {
    grid-template-columns: 1fr;
  }

  .growth-media { height: 280px; }

  .about-stats {
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
  }

  .stat { padding: 22px 8px; }
  .stat-num { font-size: 26px; }

  .advantages-grid,
  .process-steps {
    grid-template-columns: 1fr;
  }

  .hero-actions { flex-direction: column; width: 100%; }
  .hero-actions .btn { width: 100%; }

  .hide-sm { display: none; }

  .btn-login { padding: 7px 18px; }
  .brand-text { font-size: 18px; }
}