@font-face {
  font-family: 'Noto Sans SC';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('../fonts/noto-sans-sc-latin-400-normal.woff2') format('woff2'),
       url('../fonts/noto-sans-sc-chinese-simplified-400-normal.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC;
}

@font-face {
  font-family: 'Noto Sans SC';
  font-style: normal;
  font-weight: 400;
  font-display: swap;
  src: url('../fonts/noto-sans-sc-chinese-simplified-400-normal.woff2') format('woff2');
  unicode-range: U+4E00-9FFF, U+F900-FAFF;
}

@font-face {
  font-family: 'Noto Sans SC';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url('../fonts/noto-sans-sc-latin-500-normal.woff2') format('woff2'),
       url('../fonts/noto-sans-sc-chinese-simplified-500-normal.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC;
}

@font-face {
  font-family: 'Noto Sans SC';
  font-style: normal;
  font-weight: 500;
  font-display: swap;
  src: url('../fonts/noto-sans-sc-chinese-simplified-500-normal.woff2') format('woff2');
  unicode-range: U+4E00-9FFF, U+F900-FAFF;
}

@font-face {
  font-family: 'Noto Sans SC';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url('../fonts/noto-sans-sc-latin-700-normal.woff2') format('woff2'),
       url('../fonts/noto-sans-sc-chinese-simplified-700-normal.woff2') format('woff2');
  unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC;
}

@font-face {
  font-family: 'Noto Sans SC';
  font-style: normal;
  font-weight: 700;
  font-display: swap;
  src: url('../fonts/noto-sans-sc-chinese-simplified-700-normal.woff2') format('woff2');
  unicode-range: U+4E00-9FFF, U+F900-FAFF;
}

:root {
  --bg: #0a0a0a;
  --bg-alt: #101010;
  --bg-card: #141414;
  --text: #f5f5f5;
  --text-muted: #8a8a8a;
  --text-dim: #5a5a5a;
  --line: #232323;
  --accent: #2f6bff;
  --accent-soft: rgba(47, 107, 255, 0.12);
  --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", Arial, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

h1, h2, h3 {
  font-weight: 500;
  letter-spacing: -0.01em;
  line-height: 1.15;
}

a {
  color: inherit;
}

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 32px;
}

/* ===== Header ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  transition: background 0.4s var(--ease), border-color 0.4s var(--ease);
  border-bottom: 1px solid transparent;
}

.site-header.scrolled {
  background: rgba(10, 10, 10, 0.72);
  backdrop-filter: blur(20px) saturate(160%);
  -webkit-backdrop-filter: blur(20px) saturate(160%);
  border-bottom-color: var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 76px;
  padding: 0 40px;
}

.logo img {
  display: block;
  height: 26px;
  width: auto;
}

.nav {
  display: flex;
  align-items: center;
  gap: 40px;
  margin-left: auto;
}

.nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  letter-spacing: 0.03em;
  transition: color 0.3s var(--ease);
  position: relative;
}

.nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -6px;
  width: 0;
  height: 1px;
  background: var(--text);
  transition: width 0.35s var(--ease);
}

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

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

/* 移动端菜单按钮 & 下拉菜单（桌面隐藏） */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  padding: 8px;
  background: transparent;
  border: none;
  cursor: pointer;
  margin-left: auto;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition: transform 0.3s var(--ease), opacity 0.3s var(--ease);
}

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

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

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

.mobile-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  right: 0;
  z-index: 90;
  flex-direction: column;
  background: rgba(8, 10, 15, 0.98);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--line);
  padding: 8px 0 16px;
  transform: translateY(-8px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s var(--ease), transform 0.3s var(--ease);
}

.mobile-menu.open {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.mobile-menu a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 16px;
  padding: 16px 24px;
  border-bottom: 1px solid var(--line);
  transition: color 0.25s var(--ease), background 0.25s var(--ease);
}

.mobile-menu a:last-child {
  border-bottom: none;
}

.mobile-menu a:hover,
.mobile-menu a:active {
  color: var(--text);
  background: rgba(255, 255, 255, 0.03);
}

/* ===== Hero ===== */
.hero {
  position: relative;
  display: flex;
  align-items: flex-end;
  min-height: 100vh;
  overflow: hidden;
  background: #000;
}

.hero-media {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-slide {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  z-index: 0;
  animation: heroFade 8s infinite;
  will-change: opacity;
}

.slide-1 { background-image: url('../images/hero-poster.png'); }
.slide-2 { background-image: url('../images/poster_1.jpg'); animation-delay: 4s; opacity: 0; }

@keyframes heroFade {
  0%, 44%  { opacity: 1; }
  50%, 94% { opacity: 0; }
  100%     { opacity: 1; }
}

.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: linear-gradient(180deg, rgba(10,10,10,0.35) 0%, rgba(10,10,10,0.2) 40%, rgba(10,10,10,0.92) 100%);
}

.hero-content {
  position: relative;
  z-index: 2;
  width: 100%;
  padding: 0 0 8vh;
}

.hero-logo {
  display: block;
  width: min(300px, 52vw);
  height: auto;
  margin-bottom: 20px;
}

.hero-tagline {
  font-size: clamp(26px, 3.4vw, 46px);
  font-weight: 300;
  letter-spacing: 0.02em;
  color: #dcdcdc;
  line-height: 1.3;
}

/* ===== Section ===== */
.section {
  padding: 160px 0;
}

.section-eyebrow {
  font-size: 13px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 28px;
}

.section-title {
  font-size: clamp(32px, 5vw, 68px);
  font-weight: 500;
  letter-spacing: -0.02em;
  line-height: 1.12;
  max-width: 900px;
}

.section-desc {
  max-width: 640px;
  margin-top: 32px;
  color: var(--text-muted);
  font-size: 16.5px;
  line-height: 1.85;
}

/* ===== Reveal animation ===== */
.reveal {
  opacity: 0;
  transform: translateY(36px);
  transition: opacity 0.9s var(--ease), transform 0.9s var(--ease);
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

/* ===== Cards ===== */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1px;
  margin-top: 72px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.card {
  background: var(--bg);
  padding: 48px 36px;
  text-align: left;
  transition: background 0.5s var(--ease);
}

.card:hover {
  background: var(--bg-card);
}

.card-img {
  width: 100%;
  max-width: 240px;
  height: 150px;
  object-fit: contain;
  margin-bottom: 32px;
  transition: transform 0.6s var(--ease);
}

.card:hover .card-img {
  transform: scale(1.04);
}

.card h3 {
  font-size: 21px;
  font-weight: 500;
  margin-bottom: 12px;
}

.card p {
  color: var(--text-muted);
  font-size: 14.5px;
  line-height: 1.75;
}

.card-num {
  display: block;
  font-size: 13px;
  letter-spacing: 0.2em;
  color: var(--text-dim);
  margin-bottom: 20px;
}

/* ===== Contact ===== */
.contact {
  max-width: 760px;
  margin-top: 0;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.contact-item .label {
  color: #e2e2e2;
  font-size: 18px;
  font-weight: 500;
  letter-spacing: 0;
  flex-shrink: 0;
  width: 140px;
  padding-top: 4px;
}

.contact-item > span:last-child {
  font-size: 17px;
  color: var(--text);
}

.contact-address { align-items: flex-start; }

.address-block {
  display: flex;
  flex-direction: column;
  gap: 16px;
  flex: 1;
}

.address-row {
  display: flex;
  gap: 24px;
  align-items: baseline;
}

.address-name {
  color: #e2e2e2;
  font-size: 17px;
  white-space: nowrap;
  width: 96px;
  text-align: right;
}

.address-row span:last-child {
  font-size: 17px;
}

/* ===== Footer (参考大疆样式) ===== */
.site-footer {
  border-top: 1px solid var(--line);
  background: var(--bg-alt);
}

.footer-top {
  max-width: 1240px;
  margin: 0 auto;
  padding: 64px 40px 56px;
  display: grid;
  grid-template-columns: 2fr repeat(2, 1fr);
  gap: 48px;
}

.footer-brand .footer-logo {
  height: 28px;
  width: auto;
  opacity: 0.9;
  margin-bottom: 16px;
}

.footer-brand p {
  color: var(--text-dim);
  font-size: 13px;
  line-height: 1.8;
  max-width: 280px;
}

.footer-col h4 {
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  margin-bottom: 20px;
  letter-spacing: 0.05em;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 12px;
}

.footer-col a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.3s var(--ease);
}

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

.footer-bottom {
  border-top: 1px solid var(--line);
}

.footer-bottom-inner {
  max-width: 1240px;
  margin: 0 auto;
  padding: 28px 40px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-bottom .copyright {
  color: var(--text-dim);
  font-size: 13px;
}

.footer-bottom .legal-links {
  display: flex;
  gap: 28px;
}

.footer-bottom .legal-links a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 13px;
  transition: color 0.3s var(--ease);
}

.footer-bottom .legal-links a:hover {
  color: var(--text);
}

.footer-ad-desc {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 40px 28px;
  color: #4f4f4f;
  font-size: 12px;
  line-height: 1.7;
}

/* ===== Legal / Terms page ===== */
.legal-page {
  max-width: 820px;
  margin: 0 auto;
}

.legal-page h2 {
  font-size: clamp(20px, 2.4vw, 28px);
  font-weight: 500;
  margin: 56px 0 18px;
  letter-spacing: -0.01em;
}

.legal-page h2:first-of-type {
  margin-top: 0;
}

.legal-page p,
.legal-page li {
  color: var(--text-muted);
  font-size: 16px;
  line-height: 1.9;
  margin-bottom: 16px;
}

.legal-page ul {
  padding-left: 22px;
  margin-bottom: 20px;
}

.legal-page .legal-meta {
  color: var(--text-dim);
  font-size: 14px;
  margin-bottom: 48px;
}

/* ===== Page hero (inner pages) ===== */
.page-hero {
  padding: 120px 0 72px;
  border-bottom: 1px solid var(--line);
}

.page-hero .section-eyebrow {
  margin-bottom: 24px;
}

.page-hero h1 {
  font-size: clamp(32px, 4.4vw, 52px);
  font-weight: 500;
  letter-spacing: -0.01em;
}

.page-hero p {
  color: var(--text-muted);
  margin-top: 24px;
  font-size: 17px;
}

.content {
  padding: 120px 0;
}

.content-contact {
  padding: 56px 0 100px;
}

.contact-page {
  max-width: 580px;
}

.prose {
  max-width: 820px;
}

.prose h2 {
  font-size: clamp(24px, 3vw, 36px);
  font-weight: 500;
  margin: 72px 0 24px;
  letter-spacing: -0.01em;
}

.prose h2:first-child {
  margin-top: 0;
}

.prose p {
  color: var(--text-muted);
  font-size: 17px;
  line-height: 1.9;
  margin-bottom: 20px;
}

/* ===== Products list (大图平铺) ===== */
.products-list {
  padding: 0;
}

.product-panel {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 72px;
  align-items: center;
  padding: 110px 0;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  color: inherit;
}

.product-panel:nth-child(even) {
  grid-template-columns: 0.85fr 1.15fr;
}

.product-panel:nth-child(even) .product-media {
  order: 2;
}

.product-media {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.product-media img {
  width: 100%;
  max-width: 620px;
  height: auto;
  transition: transform 0.8s var(--ease);
  filter: drop-shadow(0 24px 70px rgba(47, 107, 255, 0.14));
}

.product-panel:hover .product-media img {
  transform: scale(1.05);
}

.product-num {
  display: block;
  font-size: 13px;
  letter-spacing: 0.22em;
  color: var(--text-dim);
}

.product-info h2 {
  font-size: clamp(28px, 3.6vw, 48px);
  font-weight: 500;
  letter-spacing: -0.01em;
  margin: 18px 0 22px;
}

.product-info p {
  color: var(--text-muted);
  font-size: 16.5px;
  line-height: 1.9;
  max-width: 460px;
}

.product-more {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-top: 34px;
  font-size: 14px;
  letter-spacing: 0.06em;
  color: var(--text);
  transition: gap 0.35s var(--ease), color 0.35s var(--ease);
}

.product-more::after {
  content: "\2192";
  transition: transform 0.35s var(--ease);
}

.product-panel:hover .product-more {
  gap: 16px;
  color: var(--accent);
}

/* ===== Product detail ===== */
.product-hero {
  padding: 120px 0 0;
  text-align: center;
}

.product-hero .section-eyebrow {
  margin-bottom: 20px;
}

.product-hero h1 {
  font-size: clamp(32px, 4.6vw, 56px);
  font-weight: 500;
  letter-spacing: -0.01em;
}

.product-hero p {
  color: var(--text-muted);
  margin-top: 20px;
  font-size: 17px;
}

.product-hero-img {
  display: block;
  width: 100%;
  max-width: 820px;
  height: auto;
  margin: 72px auto 0;
  filter: drop-shadow(0 30px 80px rgba(47, 107, 255, 0.16));
}

.spec-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  margin-top: 64px;
}

.spec-item {
  background: var(--bg);
  padding: 40px 32px;
}

.spec-item .spec-label {
  display: block;
  font-size: 13px;
  letter-spacing: 0.14em;
  color: var(--text-dim);
  margin-bottom: 12px;
}

.spec-item .spec-value {
  font-size: 22px;
  font-weight: 500;
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 72px;
  color: var(--text-muted);
  text-decoration: none;
  font-size: 14px;
  letter-spacing: 0.05em;
  transition: color 0.3s var(--ease), gap 0.3s var(--ease);
}

.back-link::before {
  content: "\2190";
}

.back-link:hover {
  color: var(--text);
  gap: 14px;
}

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .container { padding: 0 22px; }
  .header-inner { height: 56px; padding: 0 18px; }
  .logo img { height: 18px; }
  .nav { display: none; }
  .nav-toggle { display: flex; }
  .mobile-menu { display: flex; }
  .hero {
    min-height: 100vh;
    min-height: 100svh;
    display: flex;
    align-items: flex-end;
    padding-top: 0;
  }
  .hero-media {
    position: absolute;
    inset: 0;
    width: auto;
    aspect-ratio: auto;
    background: transparent;
  }
  .hero-slide {
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center;
  }
  .slide-2 {
    background-position: 75% center;
  }
  .hero-overlay {
    display: block;
  }
  .hero-content {
    position: relative;
    padding: 0 22px 8vh;
  }
  .hero-tagline {
    text-align: left;
    font-size: 32px;
  }
  .section { padding: 96px 0; }
  .content { padding: 72px 0; }
  .footer-top {
    grid-template-columns: 1fr 1fr;
    gap: 32px 24px;
    padding: 48px 24px;
  }
  .footer-brand { grid-column: 1 / -1; }
  .footer-bottom-inner { padding: 22px 24px; }
  .footer-ad-desc { padding: 0 24px 24px; }
  .page-hero { padding: 104px 0 56px; }
  .card { padding: 36px 24px; }
  .contact-item .label { width: 96px; }
  .product-panel,
  .product-panel:nth-child(even) {
    grid-template-columns: 1fr;
    gap: 40px;
    padding: 72px 0;
  }
  .product-panel:nth-child(even) .product-media { order: 0; }
  .product-info p { max-width: none; }
  .product-hero { padding: 104px 0 0; }
  .product-hero-img { margin-top: 48px; }
}

@media (max-width: 560px) {
  .nav {
    gap: 16px;
    overflow-x: auto;
    white-space: nowrap;
    scrollbar-width: none;
  }
  .nav::-webkit-scrollbar { display: none; }
  .nav a { font-size: 12.5px; }
  .hero-tagline { letter-spacing: 0.01em; }
  .address-row { flex-direction: column; gap: 4px; }
  .address-name { text-align: left; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  .reveal { opacity: 1; transform: none; }
}