:root {
  --bg: #FAF7F2;
  --text-primary: #2A2A2A;
  --text-secondary: #6B6B6B;
  --accent-green: #2C3E2D;
  --accent-gold: #C9A961;
  --border: #E5E0D8;
  --card-bg: #FFFFFF;
  --card-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
  --radius-card: 12px;
  --radius-btn: 8px;
  --section-spacing: 80px;
  --section-spacing-mobile: 48px;
  --nav-height: 60px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--nav-height);
}

body {
  font-family: 'Noto Sans SC', system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  font-family: 'Noto Serif SC', serif;
  font-weight: 700;
  line-height: 1.3;
}

.container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

.section-title {
  text-align: center;
  font-size: 28px;
  color: var(--accent-green);
  margin-bottom: 48px;
}

/* Navigation */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--nav-height);
  background: var(--accent-green);
  z-index: 1000;
  transition: box-shadow 0.3s ease;
}

.nav--scrolled {
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.15);
}

.nav__container {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__brand {
  font-family: 'Noto Serif SC', serif;
  font-size: 20px;
  font-weight: 700;
  color: #fff;
  text-decoration: none;
}

.nav__links {
  display: flex;
  gap: 32px;
}

.nav__links a {
  color: rgba(255, 255, 255, 0.85);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s;
}

.nav__links a:hover {
  color: #fff;
}

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

.nav__hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: #fff;
  border-radius: 1px;
  transition: transform 0.3s, opacity 0.3s;
}

/* Hero */
.hero {
  padding-top: calc(var(--nav-height) + 80px);
  padding-bottom: var(--section-spacing);
  text-align: center;
}

.hero__subtitle {
  font-size: 14px;
  color: var(--accent-gold);
  letter-spacing: 4px;
  margin-bottom: 16px;
}

.hero__title {
  font-size: 56px;
  color: var(--accent-green);
  margin-bottom: 16px;
}

.hero__desc {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 480px;
  margin: 0 auto 32px;
}

.hero__actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  margin-bottom: 48px;
}

.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: var(--radius-btn);
  font-size: 15px;
  font-weight: 500;
  text-decoration: none;
  transition: transform 0.2s, box-shadow 0.2s;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

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

.btn--secondary {
  border: 1.5px solid var(--accent-green);
  color: var(--accent-green);
}

.btn--bilibili {
  background: #00A1D6;
  color: #fff;
}

.hero__screenshot {
  max-width: 900px;
  margin: 0 auto;
}

.screenshot-img {
  width: 100%;
  border-radius: var(--radius-card);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--border);
}

/* Placeholder Images */
.placeholder-img {
  aspect-ratio: 16 / 10;
  background: var(--border);
  border-radius: var(--radius-card);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
}

.placeholder-img span {
  color: var(--text-secondary);
  font-size: 14px;
}

/* Pain Points */
.pain-points {
  padding: var(--section-spacing) 0;
  background: var(--card-bg);
}

.pain-points__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.pain-card {
  background: var(--bg);
  border-radius: var(--radius-card);
  padding: 32px 24px;
  text-align: center;
}

.pain-card__icon {
  font-size: 36px;
  margin-bottom: 16px;
}

.pain-card__title {
  font-size: 18px;
  color: var(--accent-green);
  margin-bottom: 8px;
}

.pain-card__desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Feature Sections */
.feature {
  padding: var(--section-spacing) 0;
}

.feature:nth-child(even) {
  background: var(--card-bg);
}

.feature__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.feature--reverse .feature__grid {
  direction: rtl;
}

.feature--reverse .feature__grid > * {
  direction: ltr;
}

.feature__label {
  font-size: 13px;
  color: var(--accent-gold);
  font-weight: 500;
  letter-spacing: 2px;
}

.feature__title {
  font-size: 28px;
  color: var(--accent-green);
  margin: 8px 0 16px;
}

.feature__desc {
  font-size: 15px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
}

.feature__list {
  list-style: none;
  padding: 0;
}

.feature__list li {
  position: relative;
  padding-left: 20px;
  font-size: 14px;
  color: var(--text-primary);
  line-height: 2;
}

.feature__list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 12px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent-gold);
}

/* Quick Start */
.quickstart {
  padding: var(--section-spacing) 0;
  background: var(--card-bg);
}

.quickstart__steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-bottom: 32px;
}

.step-card {
  background: var(--bg);
  border-radius: var(--radius-card);
  padding: 28px 24px;
}

.step-card__number {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--accent-gold);
  color: #fff;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 14px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
}

.step-card__title {
  font-size: 16px;
  color: var(--accent-green);
  margin-bottom: 12px;
}

.step-card__code {
  background: #1a1a2e;
  color: #e2e8f0;
  padding: 16px;
  border-radius: 8px;
  font-family: 'IBM Plex Mono', monospace;
  font-size: 13px;
  line-height: 1.7;
  overflow-x: auto;
  white-space: pre;
}

.quickstart__note {
  text-align: center;
  font-size: 13px;
  color: var(--text-secondary);
}

/* Footer */
.footer {
  background: var(--accent-green);
  color: rgba(255, 255, 255, 0.85);
  padding: 48px 0 24px;
}

.footer__content {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 32px;
}

.footer__name {
  font-family: 'Noto Serif SC', serif;
  font-size: 20px;
  font-weight: 700;
  color: #fff;
}

.footer__tagline {
  font-size: 13px;
  margin-top: 4px;
  opacity: 0.7;
}

.footer__links {
  display: flex;
  gap: 24px;
}

.footer__links a {
  color: rgba(255, 255, 255, 0.75);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s;
}

.footer__links a:hover {
  color: #fff;
}

.footer__tech {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tech-tag {
  font-size: 12px;
  padding: 4px 10px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.1);
  color: rgba(255, 255, 255, 0.8);
}

.footer__copyright {
  text-align: center;
  font-size: 13px;
  opacity: 0.6;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* Scroll Animations */
[data-animate] {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-animate].animate-visible {
  opacity: 1;
  transform: translateY(0);
}

/* Mobile Menu */
.mobile-menu {
  position: fixed;
  inset: 0;
  background: rgba(44, 62, 45, 0.97);
  z-index: 999;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 32px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.mobile-menu--open {
  opacity: 1;
  pointer-events: auto;
}

.mobile-menu a {
  color: #fff;
  text-decoration: none;
  font-size: 20px;
  font-family: 'Noto Serif SC', serif;
}

/* Responsive: Tablet */
@media (max-width: 1024px) {
  :root {
    --section-spacing: 60px;
  }

  .hero__title {
    font-size: 44px;
  }

  .feature__grid {
    gap: 32px;
  }
}

/* Responsive: Mobile */
@media (max-width: 768px) {
  :root {
    --section-spacing: var(--section-spacing-mobile);
  }

  .nav__links {
    display: none;
  }

  .nav__hamburger {
    display: flex;
  }

  .hero {
    padding-top: calc(var(--nav-height) + 48px);
  }

  .hero__title {
    font-size: 36px;
  }

  .hero__desc {
    font-size: 16px;
  }

  .hero__actions {
    flex-direction: column;
    align-items: center;
    gap: 12px;
  }

  .section-title {
    font-size: 22px;
    margin-bottom: 32px;
  }

  .pain-points__grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .feature__grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .feature--reverse .feature__grid {
    direction: ltr;
  }

  .feature__image {
    order: -1;
  }

  .feature--reverse .feature__image {
    order: -1;
  }

  .feature__title {
    font-size: 22px;
  }

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

  .footer__content {
    flex-direction: column;
    gap: 24px;
    align-items: center;
    text-align: center;
  }

  .footer__tech {
    justify-content: center;
  }
}