:root {
  --ink: #0a0a0a;
  --paper: #f5f0eb;
  --accent: #c8463b;
  --accent-soft: #e8a89f;
  --gray-100: #e8e3de;
  --gray-200: #c4bfba;
  --gray-300: #9e9994;
  --gray-400: #75706b;
  --gray-500: #4f4a46;
  --shadow: rgba(10, 10, 10, 0.08);
  --radius: 2px;
  --font: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", monospace;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font);
  background: var(--paper);
  color: var(--ink);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

/* ===== CONTAINER ===== */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* ===== HEADER ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: var(--paper);
  border-bottom: 1px solid var(--gray-100);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.site-header.scrolled {
  background: rgba(245, 240, 235, 0.92);
  backdrop-filter: blur(12px);
  box-shadow: 0 2px 24px var(--shadow);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
  padding: 0 2rem;
  max-width: 1280px;
  margin: 0 auto;
}

.logo {
  font-size: 1.6rem;
  font-weight: 900;
  letter-spacing: -0.04em;
  text-transform: uppercase;
  color: var(--ink);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.logo::before {
  content: "✦";
  font-size: 1.8rem;
  color: var(--accent);
  display: inline-block;
  animation: logoSpin 6s linear infinite;
}

@keyframes logoSpin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 2.5rem;
  list-style: none;
}

.main-nav a {
  text-decoration: none;
  color: var(--gray-500);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  position: relative;
  padding: 0.25rem 0;
  transition: color 0.3s ease;
}

.main-nav a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.main-nav a:hover {
  color: var(--ink);
}

.main-nav a:hover::after {
  width: 100%;
}

.nav-cta {
  background: var(--ink);
  color: var(--paper) !important;
  padding: 0.5rem 1.6rem !important;
  border-radius: var(--radius);
  font-weight: 600 !important;
  letter-spacing: 0.08em;
  transition: background 0.3s ease, transform 0.2s ease !important;
}

.nav-cta::after {
  display: none !important;
}

.nav-cta:hover {
  background: var(--accent) !important;
  transform: translateY(-1px);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.8rem;
  color: var(--ink);
  cursor: pointer;
  padding: 0.25rem;
  line-height: 1;
}

/* ===== HERO ===== */
.hero {
  padding: 8rem 0 6rem;
  min-height: 90vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -30%;
  right: -10%;
  width: 60%;
  height: 120%;
  background: radial-gradient(circle at 70% 50%, var(--accent-soft) 0%, transparent 70%);
  opacity: 0.25;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 640px;
}

.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 1.5rem;
  display: inline-block;
  padding: 0.3rem 1rem;
  border: 1px solid var(--accent-soft);
  border-radius: var(--radius);
}

.hero-content h1 {
  font-size: clamp(2.8rem, 7vw, 5.2rem);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: -0.04em;
  color: var(--ink);
  margin-bottom: 1.5rem;
}

.hero-content p {
  font-size: 1.15rem;
  color: var(--gray-400);
  max-width: 480px;
  margin-bottom: 2.5rem;
  line-height: 1.7;
}

.hero-buttons {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.hero-image {
  position: absolute;
  right: -2rem;
  top: 50%;
  transform: translateY(-50%);
  width: 45%;
  height: 70%;
  background: var(--gray-100);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 4rem;
  color: var(--gray-300);
  overflow: hidden;
}

.hero-image::after {
  content: "◆";
  font-size: 8rem;
  opacity: 0.15;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(5deg); }
}

/* ===== BUTTONS ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 2.2rem;
  font-family: var(--font);
  font-size: 0.85rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-decoration: none;
  border: none;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  position: relative;
}

.btn-primary {
  background: var(--ink);
  color: var(--paper);
}

.btn-primary:hover {
  background: var(--accent);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(200, 70, 59, 0.25);
}

.btn-outline {
  background: transparent;
  color: var(--ink);
  border: 1.5px solid var(--ink);
}

.btn-outline:hover {
  background: var(--ink);
  color: var(--paper);
  transform: translateY(-2px);
}

/* ===== SECTION ===== */
.section {
  padding: 6rem 0;
  position: relative;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 0.75rem;
  display: inline-block;
}

.section-title {
  font-size: clamp(2rem, 5vw, 3.4rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 1rem;
  color: var(--ink);
}

.section-desc {
  font-size: 1.05rem;
  color: var(--gray-400);
  max-width: 560px;
  line-height: 1.7;
  margin-bottom: 3rem;
}

/* ===== CARDS GRID ===== */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}

.category-card {
  background: var(--paper);
  border: 1px solid var(--gray-100);
  padding: 2.5rem 2rem;
  border-radius: var(--radius);
  transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  position: relative;
  overflow: hidden;
}

.category-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 3px;
  height: 0;
  background: var(--accent);
  transition: height 0.4s ease;
}

.category-card:hover {
  border-color: var(--ink);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px var(--shadow);
}

.category-card:hover::before {
  height: 100%;
}

.card-icon {
  font-size: 2.4rem;
  margin-bottom: 1.2rem;
  display: block;
  color: var(--accent);
}

.category-card h3 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 0.6rem;
  letter-spacing: -0.02em;
}

.category-card p {
  font-size: 0.9rem;
  color: var(--gray-400);
  line-height: 1.6;
  margin-bottom: 1.2rem;
}

.card-link {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--ink);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  transition: gap 0.3s ease;
}

.card-link::after {
  content: "→";
  transition: transform 0.3s ease;
}

.card-link:hover {
  gap: 0.8rem;
}

.card-link:hover::after {
  transform: translateX(4px);
}

/* ===== FEATURE BLOCK ===== */
.feature-block {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
  padding: 2rem 0;
}

.feature-image {
  background: var(--gray-100);
  aspect-ratio: 4/3;
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  color: var(--gray-300);
  position: relative;
  overflow: hidden;
}

.feature-image::after {
  content: "▣";
  font-size: 6rem;
  opacity: 0.1;
}

.feature-text {
  padding-right: 1rem;
}

.feature-text h3 {
  font-size: 1.8rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 1rem;
}

.feature-text p {
  color: var(--gray-400);
  line-height: 1.7;
  margin-bottom: 1.5rem;
}

.feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.feature-list li {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.95rem;
  color: var(--gray-500);
}

.feature-list li::before {
  content: "—";
  color: var(--accent);
  font-weight: 700;
}

/* ===== STATS BAR ===== */
.stats-bar {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
  padding: 4rem 0;
  border-top: 1px solid var(--gray-100);
  border-bottom: 1px solid var(--gray-100);
  margin: 2rem 0;
}

.stat-item {
  text-align: center;
}

.stat-number {
  font-size: clamp(2.8rem, 5vw, 4.2rem);
  font-weight: 900;
  letter-spacing: -0.04em;
  color: var(--ink);
  line-height: 1;
  margin-bottom: 0.3rem;
}

.stat-label {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--gray-400);
  font-weight: 500;
}

/* ===== CONTENT WALL ===== */
.content-wall {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.5rem;
}

.content-wall-item {
  background: var(--paper);
  border: 1px solid var(--gray-100);
  padding: 2rem;
  border-radius: var(--radius);
  transition: all 0.3s ease;
  position: relative;
}

.content-wall-item:hover {
  border-color: var(--ink);
  transform: scale(1.01);
}

.content-wall-body h4 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.content-wall-body p {
  font-size: 0.9rem;
  color: var(--gray-400);
  line-height: 1.6;
}

/* ===== FAQ ===== */
.faq-list {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.faq-item {
  border: 1px solid var(--gray-100);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.3s ease;
}

.faq-item:hover {
  border-color: var(--gray-200);
}

.faq-item summary {
  padding: 1.2rem 1.5rem;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background 0.2s ease;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  font-size: 1.4rem;
  font-weight: 300;
  color: var(--accent);
  transition: transform 0.3s ease;
}

.faq-item[open] summary::after {
  content: "−";
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 1.5rem 1.2rem;
  color: var(--gray-400);
  line-height: 1.7;
  font-size: 0.95rem;
}

/* ===== CTA BANNER ===== */
.cta-banner {
  background: var(--ink);
  color: var(--paper);
  padding: 4rem 3rem;
  border-radius: var(--radius);
  text-align: center;
  margin: 4rem 0;
  position: relative;
  overflow: hidden;
}

.cta-banner::before {
  content: "✦";
  position: absolute;
  top: -20%;
  right: -10%;
  font-size: 20rem;
  opacity: 0.04;
  pointer-events: none;
}

.cta-banner h2 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  margin-bottom: 1rem;
}

.cta-banner p {
  color: var(--gray-200);
  max-width: 480px;
  margin: 0 auto 2rem;
  font-size: 1.05rem;
  line-height: 1.6;
}

.cta-banner .btn-primary {
  background: var(--paper);
  color: var(--ink);
}

.cta-banner .btn-primary:hover {
  background: var(--accent);
  color: var(--paper);
  box-shadow: 0 8px 24px rgba(200, 70, 59, 0.3);
}

/* ===== FOOTER ===== */
.site-footer {
  border-top: 1px solid var(--gray-100);
  padding: 4rem 0 2rem;
  margin-top: 4rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand .logo {
  margin-bottom: 1rem;
}

.footer-brand p {
  font-size: 0.9rem;
  color: var(--gray-400);
  max-width: 280px;
  line-height: 1.7;
}

.footer-col h4 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  margin-bottom: 1.2rem;
  color: var(--gray-500);
  font-weight: 600;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.footer-col a {
  text-decoration: none;
  color: var(--gray-400);
  font-size: 0.9rem;
  transition: color 0.3s ease;
}

.footer-col a:hover {
  color: var(--ink);
}

.footer-bottom {
  border-top: 1px solid var(--gray-100);
  padding-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: var(--gray-400);
}

/* ===== UTILITY ===== */
.text-accent {
  color: var(--accent);
}

.text-center {
  text-align: center;
}

.seo-description {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .container {
    padding: 0 1.2rem;
  }

  .header-inner {
    padding: 0 1.2rem;
  }

  .main-nav {
    position: fixed;
    top: 72px;
    left: 0;
    width: 100%;
    background: var(--paper);
    flex-direction: column;
    padding: 2rem;
    gap: 1.5rem;
    border-bottom: 1px solid var(--gray-100);
    transform: translateY(-120%);
    opacity: 0;
    transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    pointer-events: none;
  }

  .main-nav.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .menu-toggle {
    display: block;
  }

  .hero {
    padding: 6rem 0 4rem;
    min-height: auto;
  }

  .hero-image {
    position: relative;
    right: auto;
    top: auto;
    transform: none;
    width: 100%;
    height: 240px;
    margin-top: 2rem;
  }

  .hero-content h1 {
    font-size: 2.4rem;
  }

  .feature-block {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .feature-image {
    order: -1;
  }

  .stats-bar {
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
  }

  .cta-banner {
    padding: 3rem 1.5rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 1rem;
  }

  .header-inner {
    height: 64px;
    padding: 0 1rem;
  }

  .main-nav {
    top: 64px;
  }

  .logo {
    font-size: 1.3rem;
  }

  .hero {
    padding: 5rem 0 3rem;
  }

  .hero-content h1 {
    font-size: 2rem;
  }

  .hero-buttons {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    text-align: center;
  }

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

  .content-wall {
    grid-template-columns: 1fr;
  }

  .stats-bar {
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    padding: 2rem 0;
  }

  .stat-number {
    font-size: 2rem;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .section {
    padding: 3rem 0;
  }

  .cta-banner {
    padding: 2.5rem 1.2rem;
  }

  .cta-banner h2 {
    font-size: 1.6rem;
  }
}