/* ===== CSS Variables & Reset ===== */
:root {
  --bg-dark: #1b1e24;
  --bg-dark-alt: #21252d;
  --bg-light: #fafaf8;
  --bg-section: #f4f2ed;
  --bg-gray: #efeee9;
  --bg-card: #ffffff;
  --text: #333333;
  --text-secondary: #555555;
  --text-light: #e5e3de;
  --text-muted: #999999;
  --accent: #d4703a;
  --accent-hover: #c0632f;
  --accent-bg: rgba(212, 112, 58, 0.07);
  --accent2: #4a8faa;
  --accent2-bg: rgba(74, 143, 170, 0.08);
  --border: #e5e2db;
  --border-light: rgba(229, 227, 222, 0.1);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.04);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.06);
  --radius: 10px;
  --radius-lg: 14px;
  --font: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
  --max-w: 920px;
  --nav-h: 56px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-h) + 16px);
}

body {
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.85;
  color: var(--text);
  background: var(--bg-light);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 32px;
}

/* ===== Navigation ===== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-h);
  z-index: 100;
  background: rgba(27, 30, 36, 0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: background 0.3s, box-shadow 0.3s;
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 32px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-light);
  letter-spacing: 2px;
  opacity: 0.9;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav-links a {
  font-size: 13px;
  color: rgba(229, 227, 222, 0.5);
  transition: color 0.25s;
  letter-spacing: 0.5px;
}

.nav-links a:hover { color: var(--text-light); }

.nav-cta {
  background: var(--accent);
  color: #fff !important;
  padding: 6px 18px;
  border-radius: 5px;
  font-weight: 500;
  opacity: 1 !important;
}

.nav-cta:hover { background: var(--accent-hover); }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px 4px;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--text-light);
  transition: transform 0.3s, opacity 0.3s;
}

/* ===== Hero ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(160deg, #1b1e24 0%, #252830 35%, #1d2530 65%, #1b1e24 100%);
  z-index: 0;
}

.hero-bg::before {
  content: '';
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(255,255,255,0.03) 1px, transparent 1px);
  background-size: 32px 32px;
}

.hero-bg::after {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 500px 350px at 15% 45%, rgba(74, 143, 170, 0.06) 0%, transparent 70%),
    radial-gradient(ellipse 400px 250px at 85% 25%, rgba(212, 112, 58, 0.04) 0%, transparent 70%);
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 140px 32px 100px;
  max-width: 720px;
}

.hero-title {
  font-size: 38px;
  font-weight: 700;
  color: var(--text-light);
  line-height: 1.35;
  margin-bottom: 28px;
  letter-spacing: 1px;
}

.hero-subtitle {
  font-size: 17px;
  color: rgba(229, 227, 222, 0.75);
  max-width: 580px;
  margin: 0 auto 24px;
  line-height: 1.9;
}

.hero-note {
  font-size: 14px;
  color: rgba(153, 153, 153, 0.8);
  margin-bottom: 48px;
  line-height: 1.9;
}

.hero-buttons {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ===== Buttons ===== */
.btn {
  display: inline-block;
  padding: 11px 26px;
  border-radius: 6px;
  font-size: 14px;
  font-weight: 500;
  transition: all 0.25s;
  cursor: pointer;
  border: none;
  letter-spacing: 0.3px;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover {
  background: var(--accent-hover);
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(212, 112, 58, 0.2);
}

.btn-outline {
  background: transparent;
  color: rgba(229, 227, 222, 0.7);
  border: 1px solid rgba(229, 227, 222, 0.18);
}

.btn-outline:hover {
  border-color: rgba(229, 227, 222, 0.4);
  color: var(--text-light);
  background: rgba(255, 255, 255, 0.03);
}

/* ===== Sections ===== */
.section {
  padding: 110px 0;
}

.section-light { background: var(--bg-light); }
.section-gray { background: var(--bg-section); }
.section-dark { background: var(--bg-dark); color: var(--text-light); }

.section-title {
  font-size: 26px;
  font-weight: 600;
  margin-bottom: 44px;
  line-height: 1.45;
  letter-spacing: 0.3px;
}

.section-dark .section-title { color: var(--text-light); }

.section-summary {
  margin-top: 56px;
  font-size: 15px;
  color: var(--text-muted);
  text-align: center;
  line-height: 1.9;
}

/* ===== Prose ===== */
.prose p {
  margin-bottom: 18px;
  line-height: 1.95;
  color: var(--text-secondary);
}

.prose-light p { color: rgba(229, 227, 222, 0.78); }

.prose blockquote {
  border-left: 2px solid var(--accent);
  padding: 18px 28px;
  margin: 28px 0;
  font-size: 16px;
  font-weight: 500;
  color: var(--text);
  background: var(--accent-bg);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.section-dark .prose blockquote {
  background: rgba(212, 112, 58, 0.08);
  color: var(--text-light);
}

.prose ul {
  padding-left: 20px;
  margin: 18px 0;
}

.prose ul li {
  position: relative;
  padding-left: 18px;
  margin-bottom: 10px;
  color: var(--text-secondary);
}

.prose ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 12px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent);
  opacity: 0.6;
}

.highlight-text {
  font-size: 19px;
  font-weight: 600;
  color: var(--accent);
  margin: 28px 0;
}

.section-dark .highlight-text { color: var(--accent); }

/* ===== Audience Cards ===== */
.audience-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 28px;
}

.audience-card {
  padding: 36px 32px;
  border-radius: var(--radius-lg);
  background: var(--bg-card);
  box-shadow: var(--shadow-sm);
}

.audience-card h3 {
  font-size: 16px;
  margin-bottom: 24px;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.audience-yes h3 { color: var(--accent2); }
.audience-no h3 { color: var(--text-muted); }

.audience-card li {
  position: relative;
  padding-left: 26px;
  margin-bottom: 12px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--text-secondary);
}

.audience-yes li::before {
  content: '\2713';
  position: absolute;
  left: 0;
  color: var(--accent2);
  font-weight: 600;
  font-size: 13px;
}

.audience-no li::before {
  content: '\2717';
  position: absolute;
  left: 0;
  color: #ccc;
  font-size: 13px;
}

/* ===== Three Layer Cards ===== */
.three-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 56px;
}

.layer-card {
  padding: 40px 28px 36px;
  background: var(--bg-section);
  border-radius: var(--radius-lg);
  text-align: center;
  transition: transform 0.25s, box-shadow 0.25s;
}

.layer-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.layer-num {
  font-size: 32px;
  font-weight: 700;
  color: var(--accent);
  opacity: 0.2;
  margin-bottom: 16px;
  line-height: 1;
}

.layer-card h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 16px;
  color: var(--text);
}

.layer-card p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 2;
}

.meta-result-label {
  font-weight: 500;
  margin-top: 28px;
  color: var(--text);
}

.meta-results {
  padding-left: 20px;
  margin: 14px 0 0;
}

.meta-results li {
  position: relative;
  padding-left: 18px;
  margin-bottom: 8px;
  color: var(--text-secondary);
}

.meta-results li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 12px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent2);
  opacity: 0.6;
}

/* ===== Method Flow ===== */
.method-flow {
  display: flex;
  align-items: flex-start;
  gap: 0;
  justify-content: center;
}

.method-step {
  flex: 1;
  max-width: 260px;
  text-align: center;
  padding: 0 20px;
}

.method-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 76px;
  height: 76px;
  border-radius: 50%;
  background: var(--bg-card);
  font-size: 18px;
  font-weight: 700;
  color: var(--accent);
  margin-bottom: 24px;
  border: 1.5px solid var(--accent);
  box-shadow: var(--shadow-sm);
  letter-spacing: 2px;
}

.method-step p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.85;
}

.method-arrow {
  width: 36px;
  height: 1.5px;
  background: var(--border);
  margin-top: 38px;
  position: relative;
  flex-shrink: 0;
}

.method-arrow::after {
  content: '';
  position: absolute;
  right: -1px;
  top: -3.5px;
  border: 4px solid transparent;
  border-left-color: var(--border);
}

/* ===== V1 Logic ===== */
.v1-logic {
  margin-top: 56px;
  padding: 44px 40px;
  background: var(--bg-section);
  border-radius: var(--radius-lg);
}

.v1-logic h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 18px;
  color: var(--accent2);
}

.v1-logic p {
  color: var(--text-secondary);
}

.v1-logic ul {
  padding-left: 20px;
  margin: 14px 0 24px;
}

.v1-logic li {
  position: relative;
  padding-left: 18px;
  margin-bottom: 10px;
  color: var(--text-secondary);
}

.v1-logic li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 12px;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--accent2);
  opacity: 0.6;
}

.golden-quote {
  border-left: 2px solid var(--accent);
  padding: 22px 28px;
  margin: 28px 0 0;
  font-size: 17px;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-bg);
  border-radius: 0 var(--radius) var(--radius) 0;
}

/* ===== Value List ===== */
.value-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-top: 36px;
}

.value-item {
  display: flex;
  align-items: flex-start;
  gap: 18px;
  padding: 28px;
  background: var(--bg-card);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
}

.value-num {
  flex-shrink: 0;
  width: 34px;
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
}

.value-item p {
  font-size: 15px;
  line-height: 1.75;
  padding-top: 5px;
  color: var(--text-secondary);
}

/* ===== Service Cards ===== */
.service-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.service-card {
  padding: 36px 24px 32px;
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  transition: transform 0.25s, box-shadow 0.25s;
}

.service-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
}

.service-card-highlight {
  border-color: var(--accent);
  position: relative;
}

.service-card-highlight::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--accent);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.service-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 4px;
  background: var(--accent2-bg);
  color: var(--accent2);
  margin-bottom: 18px;
  letter-spacing: 1px;
  text-transform: uppercase;
}

.service-card-highlight .service-tag {
  background: var(--accent-bg);
  color: var(--accent);
}

.service-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 14px;
  color: var(--text);
}

.service-card p {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.75;
}

.service-notice {
  margin-top: 52px;
  padding: 28px 36px;
  background: var(--bg-section);
  border-left: 2px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  text-align: center;
}

.service-notice p {
  font-size: 15px;
  font-weight: 500;
  color: var(--text-secondary);
  line-height: 1.85;
}

/* ===== FAQ ===== */
.faq-list {
  max-width: 700px;
  margin: 0 auto;
}

.faq-item {
  border-bottom: 1px solid var(--border-light);
}

.faq-q {
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  padding: 28px 44px 28px 0;
  font-size: 15px;
  font-weight: 500;
  color: rgba(229, 227, 222, 0.85);
  cursor: pointer;
  position: relative;
  font-family: var(--font);
  line-height: 1.65;
  transition: color 0.2s;
}

.faq-q:hover { color: var(--text-light); }

.faq-q::after {
  content: '+';
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  font-weight: 300;
  color: rgba(153, 153, 153, 0.5);
  transition: transform 0.3s, color 0.3s;
}

.faq-item.active .faq-q::after {
  content: '\2212';
  color: var(--accent);
}

.faq-a {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.4s cubic-bezier(0.4, 0, 0.2, 1),
              padding 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.faq-item.active .faq-a {
  max-height: 500px;
  padding-bottom: 28px;
}

.faq-a p {
  font-size: 14px;
  color: rgba(229, 227, 222, 0.6);
  line-height: 1.9;
  margin-bottom: 10px;
}

.faq-a strong { color: var(--accent); }

/* ===== CTA Section ===== */
.section-cta {
  padding: 110px 0;
  background: linear-gradient(160deg, #1b1e24 0%, #252830 50%, #1d2530 100%);
  text-align: center;
}

.cta-title {
  font-size: 22px;
  font-weight: 600;
  color: var(--text-light);
  max-width: 640px;
  margin: 0 auto 28px;
  line-height: 1.55;
}

.cta-text {
  font-size: 15px;
  color: rgba(229, 227, 222, 0.6);
  margin-bottom: 48px;
  line-height: 1.85;
}

.cta-qr-grid {
  display: flex;
  gap: 48px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 28px;
}

.cta-qr-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}

.cta-qr-img {
  width: 168px;
  height: 168px;
  border-radius: var(--radius);
  background: #fff;
  padding: 10px;
  object-fit: contain;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
}

.cta-qr-label {
  font-size: 13px;
  color: var(--text-muted);
  letter-spacing: 0.5px;
}

.cta-note {
  font-size: 13px;
  color: rgba(153, 153, 153, 0.6);
  margin-bottom: 36px;
}

.cta-closing {
  font-size: 14px;
  color: rgba(229, 227, 222, 0.4);
  line-height: 1.85;
}

/* ===== Footer ===== */
.footer {
  padding: 36px 0;
  background: var(--bg-dark);
  text-align: center;
  border-top: 1px solid rgba(229, 227, 222, 0.05);
}

.footer-slogan {
  font-size: 13px;
  color: rgba(153, 153, 153, 0.5);
  margin-bottom: 4px;
  letter-spacing: 0.5px;
}

.footer-sub {
  font-size: 12px;
  color: rgba(153, 153, 153, 0.3);
}

/* ===== Scroll Animations ===== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1),
              transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ===== Responsive: Tablet ===== */
@media (max-width: 1024px) {
  .service-grid { grid-template-columns: 1fr 1fr; }
}

/* ===== Responsive: Mobile ===== */
@media (max-width: 768px) {
  :root { --nav-h: 52px; }
  .container { padding: 0 20px; }
  .nav-toggle { display: flex; }

  .nav-links {
    display: none;
    position: absolute;
    top: var(--nav-h);
    left: 0;
    right: 0;
    background: rgba(27, 30, 36, 0.98);
    flex-direction: column;
    padding: 12px 20px 20px;
    gap: 0;
  }

  .nav-links.open { display: flex; }
  .nav-links li { width: 100%; }

  .nav-links a {
    display: block;
    padding: 14px 0;
    font-size: 15px;
    border-bottom: 1px solid rgba(229, 227, 222, 0.05);
  }

  .nav-cta { text-align: center; margin-top: 8px; padding: 10px 18px; }

  .hero { min-height: auto; }
  .hero-content { padding: 100px 20px 64px; }
  .hero-title { font-size: 26px; margin-bottom: 20px; }
  .hero-subtitle { font-size: 15px; line-height: 1.85; }
  .hero-note { font-size: 13px; margin-bottom: 36px; }
  .hero-buttons { gap: 10px; }
  .btn { padding: 12px 22px; font-size: 14px; min-height: 44px; }

  .section { padding: 72px 0; }
  .section-title { font-size: 21px; margin-bottom: 32px; line-height: 1.5; }
  .section-summary { margin-top: 40px; font-size: 14px; }

  .prose p { font-size: 15px; margin-bottom: 16px; }
  .prose blockquote { padding: 14px 20px; font-size: 15px; }
  .highlight-text { font-size: 17px; }

  .audience-grid { grid-template-columns: 1fr; gap: 16px; }
  .audience-card { padding: 28px 24px; }
  .audience-card li { font-size: 14px; }

  .three-cards { grid-template-columns: 1fr; gap: 16px; }
  .layer-card { padding: 32px 24px 28px; }

  .value-list { grid-template-columns: 1fr; gap: 14px; }
  .value-item { padding: 22px 20px; }

  .service-grid { grid-template-columns: 1fr; gap: 14px; }
  .service-card { padding: 28px 22px 24px; }
  .service-notice { padding: 22px 20px; margin-top: 36px; }
  .service-notice p { font-size: 14px; }

  .method-flow { flex-direction: column; align-items: center; gap: 8px; }

  .method-arrow {
    width: 1.5px;
    height: 20px;
    margin: 0;
  }

  .method-arrow::after {
    right: auto;
    left: -3.5px;
    top: auto;
    bottom: -1px;
    border: 4px solid transparent;
    border-top-color: var(--border);
    border-left-color: transparent;
  }

  .method-step { max-width: 100%; padding: 0 8px; }
  .method-icon { width: 68px; height: 68px; font-size: 16px; }

  .v1-logic { padding: 28px 22px; margin-top: 40px; }
  .golden-quote { padding: 18px 20px; font-size: 16px; }

  .faq-q { padding: 22px 40px 22px 0; font-size: 15px; min-height: 48px; }
  .faq-a p { font-size: 14px; }

  .section-cta { padding: 72px 0; }
  .cta-title { font-size: 19px; }
  .cta-text { margin-bottom: 36px; }
  .cta-qr-grid { gap: 32px; }
  .cta-qr-img { width: 148px; height: 148px; }
}

@media (max-width: 380px) {
  .hero-title { font-size: 23px; }
  .section-title { font-size: 19px; }
  .hero-buttons { flex-direction: column; align-items: center; }
  .btn { width: 100%; text-align: center; }
}