/* ===== 悠君科技 - 企业官网样式 ===== */
/* 设计风格：蓝白灰高级配色、极简、科技感、专业可信 */

:root {
  /* 主色系 - 高级蓝灰 */
  --color-primary: #0a3d62;
  --color-primary-light: #1e5a8a;
  --color-primary-dark: #062a42;
  --color-accent: #00b4d8;
  --color-accent-dim: rgba(0, 180, 216, 0.15);
  
  /* 中性色 */
  --color-white: #ffffff;
  --color-gray-50: #f8fafc;
  --color-gray-100: #f1f5f9;
  --color-gray-200: #e2e8f0;
  --color-gray-300: #cbd5e1;
  --color-gray-400: #94a3b8;
  --color-gray-500: #64748b;
  --color-gray-600: #475569;
  --color-gray-700: #334155;
  --color-gray-800: #1e293b;
  --color-gray-900: #0f172a;
  
  /* 语义色 */
  --color-bg: #0a0e17;
  --color-bg-elevated: #111827;
  --color-text: #e2e8f0;
  --color-text-muted: #94a3b8;
  
  /* 排版 */
  --font-sans: "Noto Sans SC", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;
  --font-size-5xl: 3rem;
  
  /* 间距与尺寸 */
  --container-max: 1200px;
  --header-height: 72px;
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  
  /* 过渡 */
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s ease;
  --transition-slow: 0.4s ease;
}

/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ===== Section Header ===== */
.section-header {
  text-align: center;
  margin-bottom: 3.5rem;
}

.section-header__tag {
  display: inline-block;
  font-size: var(--font-size-xs);
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: 0.75rem;
}

.section-header__title {
  font-size: var(--font-size-3xl);
  font-weight: 600;
  color: var(--color-white);
  margin-bottom: 0.5rem;
  letter-spacing: -0.02em;
}

.section-header__subtitle {
  font-size: var(--font-size-base);
  color: var(--color-text-muted);
  font-weight: 400;
}

/* ===== Buttons ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 1.5rem;
  font-family: var(--font-sans);
  font-size: var(--font-size-sm);
  font-weight: 500;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-base);
}

.btn--primary {
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
  color: var(--color-white);
  box-shadow: 0 4px 14px rgba(10, 61, 98, 0.4);
}

.btn--primary:hover {
  background: linear-gradient(135deg, var(--color-accent), var(--color-primary-light));
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(0, 180, 216, 0.3);
}

.btn--outline {
  background: transparent;
  color: var(--color-accent);
  border: 1.5px solid rgba(0, 180, 216, 0.5);
}

.btn--outline:hover {
  background: var(--color-accent-dim);
  border-color: var(--color-accent);
}

.btn--sm {
  padding: 0.5rem 1rem;
  font-size: var(--font-size-xs);
}

.btn--lg {
  padding: 1rem 2rem;
  font-size: var(--font-size-base);
}

/* ===== Header ===== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  z-index: 1000;
  transition: all var(--transition-base);
}

.header--scrolled {
  background: rgba(10, 14, 23, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
}

.header__logo {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--color-white);
  letter-spacing: -0.02em;
}

.header__nav-wrap {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.header__nav {
  display: flex;
  gap: 2rem;
}

.header__link {
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
}

.header__link:hover {
  color: var(--color-accent);
}

.header__actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.header__lang {
  background: none;
  border: none;
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  transition: color var(--transition-fast);
}

.header__lang:hover {
  color: var(--color-accent);
}

.header__menu-btn {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.header__menu-btn span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text);
  transition: transform var(--transition-base);
}

/* ===== Hero Section ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding: var(--header-height) 1.5rem 4rem;
  overflow: hidden;
}

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

.hero__grid {
  position: absolute;
  inset: 0;
  background-image: 
    linear-gradient(rgba(0, 180, 216, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 180, 216, 0.03) 1px, transparent 1px);
  background-size: 60px 60px;
}

.hero__gradient {
  position: absolute;
  inset: 0;
  background: 
    radial-gradient(ellipse 80% 50% at 50% -20%, rgba(0, 180, 216, 0.15), transparent),
    radial-gradient(ellipse 60% 40% at 100% 50%, rgba(10, 61, 98, 0.3), transparent),
    radial-gradient(ellipse 50% 30% at 0% 80%, rgba(10, 61, 98, 0.2), transparent);
}

.hero__canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0.6;
}

.hero__glow {
  position: absolute;
  width: 400px;
  height: 400px;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.2;
  animation: glowPulse 8s ease-in-out infinite;
}

.hero__glow--1 {
  top: -100px;
  right: -100px;
  background: var(--color-accent);
}

.hero__glow--2 {
  bottom: -150px;
  left: -100px;
  background: var(--color-primary);
}

@keyframes glowPulse {
  0%, 100% { opacity: 0.15; transform: scale(1); }
  50% { opacity: 0.25; transform: scale(1.1); }
}

.hero__content {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 4rem;
  max-width: var(--container-max);
  margin: 0 auto;
  width: 100%;
}

.hero__text {
  flex: 1;
  max-width: 600px;
}

.hero__title {
  font-size: clamp(2rem, 4vw, var(--font-size-4xl));
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-white);
  letter-spacing: -0.03em;
  margin-bottom: 1.5rem;
}

.hero__subtitle {
  font-size: var(--font-size-lg);
  color: var(--color-text-muted);
  line-height: 1.7;
  margin-bottom: 2rem;
  max-width: 520px;
}

.hero__btns {
  display: flex;
  gap: 1rem;
}

.hero__visual {
  flex-shrink: 0;
}

.hero__illustration {
  position: relative;
  width: 320px;
  height: 320px;
}

.hero__nodes .node {
  position: absolute;
  width: 8px;
  height: 8px;
  background: var(--color-accent);
  border-radius: 50%;
  box-shadow: 0 0 20px var(--color-accent);
  animation: nodePulse 2s ease-in-out infinite;
}

.node--1 { top: 10%; left: 20%; animation-delay: 0s; }
.node--2 { top: 20%; right: 15%; animation-delay: 0.3s; }
.node--3 { top: 50%; left: 5%; animation-delay: 0.6s; }
.node--4 { top: 60%; right: 10%; animation-delay: 0.9s; }
.node--5 { bottom: 20%; left: 25%; animation-delay: 1.2s; }
.node--6 { bottom: 15%; right: 20%; animation-delay: 1.5s; }

@keyframes nodePulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.6; transform: scale(1.2); }
}

.hero__lines {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero__lines .line {
  stroke: rgba(0, 180, 216, 0.2);
  stroke-width: 0.5;
  stroke-dasharray: 4 4;
  animation: lineFlow 3s linear infinite;
}

.hero__lines .line--diag {
  stroke: rgba(0, 180, 216, 0.1);
}

@keyframes lineFlow {
  to { stroke-dashoffset: -16; }
}

.hero__cube {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 80px;
  height: 80px;
  margin: -40px 0 0 -40px;
  border: 1px solid rgba(0, 180, 216, 0.3);
  animation: cubeRotate 20s linear infinite;
}

@keyframes cubeRotate {
  to { transform: rotate(360deg); }
}

.hero__scroll {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  animation: scrollBounce 2s ease-in-out infinite;
}

.hero__scroll-line {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, var(--color-accent), transparent);
  border-radius: 2px;
}

@keyframes scrollBounce {
  0%, 100% { transform: translateX(-50%) translateY(0); }
  50% { transform: translateX(-50%) translateY(6px); }
}

/* ===== About Section ===== */
.about {
  padding: 6rem 0;
  background: var(--color-bg-elevated);
}

.about__content {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 4rem;
  align-items: start;
}

.about__text {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.about__lead {
  font-size: var(--font-size-lg);
  color: var(--color-text);
  font-weight: 500;
  line-height: 1.7;
}

.about__para {
  font-size: var(--font-size-base);
  color: var(--color-text-muted);
  line-height: 1.8;
}

.about__stats {
  display: flex;
  gap: 3rem;
  margin-top: 1.5rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.stat {
  display: flex;
  flex-direction: column;
}

.stat__num {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 0.25rem;
}

.stat__label {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

.about__card {
  position: relative;
  padding: 2rem;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.about__card-bg {
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(0, 180, 216, 0.08), rgba(10, 61, 98, 0.15));
}

.about__card-content {
  position: relative;
  z-index: 1;
}

.about__card-content h3 {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--color-white);
  margin-bottom: 0.5rem;
}

.about__card-content p {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

/* ===== Services Section ===== */
.services {
  padding: 6rem 0;
  background: var(--color-bg);
}

.services__grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

.service-card {
  position: relative;
  padding: 2rem;
  background: var(--color-bg-elevated);
  border-radius: var(--radius-lg);
  border: 1px solid rgba(255, 255, 255, 0.06);
  transition: all var(--transition-base);
  overflow: hidden;
}

.service-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--color-accent), transparent);
  opacity: 0;
  transition: opacity var(--transition-base);
}

.service-card:hover {
  transform: translateY(-4px);
  border-color: rgba(0, 180, 216, 0.2);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.2);
}

.service-card:hover::before {
  opacity: 1;
}

.service-card__icon {
  width: 48px;
  height: 48px;
  margin-bottom: 1.25rem;
  color: var(--color-accent);
}

.service-card__icon svg {
  width: 100%;
  height: 100%;
}

.service-card__title {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-white);
  margin-bottom: 0.75rem;
  line-height: 1.3;
}

.service-card__desc {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  line-height: 1.6;
}

/* ===== Solutions & Research Sections ===== */
.solutions, .research {
  padding: 5rem 0;
  background: var(--color-bg-elevated);
}

.solutions__coming, .research__coming {
  text-align: center;
  padding: 3rem;
  font-size: var(--font-size-base);
  color: var(--color-text-muted);
  border: 1px dashed rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-lg);
}

/* ===== Contact Section ===== */
.contact {
  padding: 6rem 0;
  background: var(--color-bg);
}

.contact__content {
  max-width: 560px;
  margin: 0 auto;
  text-align: center;
}

.contact__info {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.contact__item {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.contact__label {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.contact__value {
  font-size: var(--font-size-lg);
  color: var(--color-white);
}

.contact__link {
  color: var(--color-accent);
  transition: opacity var(--transition-fast);
}

.contact__link:hover {
  opacity: 0.8;
}

/* ===== Footer ===== */
.footer {
  padding: 3rem 0;
  background: var(--color-bg-elevated);
  border-top: 1px solid rgba(255, 255, 255, 0.06);
}

.footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.footer__logo {
  font-size: var(--font-size-lg);
  font-weight: 600;
  color: var(--color-white);
}

.footer__tagline {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
  margin-top: 0.25rem;
}

.footer__links {
  display: flex;
  gap: 2rem;
}

.footer__links a {
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  transition: color var(--transition-fast);
}

.footer__links a:hover {
  color: var(--color-accent);
}

.footer__copy {
  font-size: var(--font-size-xs);
  color: var(--color-text-muted);
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .hero__visual {
    display: none;
  }

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

  .about__visual {
    order: -1;
  }

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

@media (max-width: 768px) {
  .header__nav-wrap {
    position: fixed;
    top: var(--header-height);
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 1rem;
    background: rgba(10, 14, 23, 0.98);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
  }

  .header__nav-wrap.is-visible {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .header__nav {
    flex-direction: column;
    gap: 0;
  }

  .header__nav .header__link {
    display: block;
    padding: 1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  }

  .header__actions {
    flex-direction: row;
    justify-content: center;
    padding: 1rem;
    gap: 1rem;
    border-top: 1px solid rgba(255, 255, 255, 0.06);
  }

  .header__menu-btn {
    display: flex;
  }

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

  .header__menu-btn.is-open span:nth-child(2) {
    opacity: 0;
  }

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

  body.menu-open {
    overflow: hidden;
  }

  .hero__title {
    font-size: var(--font-size-2xl);
  }

  .hero__subtitle {
    font-size: var(--font-size-base);
  }

  .hero__btns {
    flex-direction: column;
  }

  .hero__btns .btn {
    width: 100%;
  }

  .about__stats {
    flex-direction: column;
    gap: 1.5rem;
  }

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

  .section-header__title {
    font-size: var(--font-size-2xl);
  }

  .footer__inner {
    flex-direction: column;
    text-align: center;
  }
}

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