:root {
  --navy: #0a192f;
  --light-navy: #112240;
  --lighter-navy: #233554;
  --gold: #f6c344;
  --light-gold: #f9e4a6;
  --dark-gold: #c99a2e;
  --cream: #faf8f3;
  --white: #ffffff;
  --slate: #8892b0;
  --light-slate: #ccd6f6;
  --shadow: rgba(2, 12, 27, 0.7);
  --shadow-sm: rgba(2, 12, 27, 0.15);
  --radius: 8px;
  --radius-lg: 12px;
  --transition: all 0.25s cubic-bezier(0.645, 0.045, 0.355, 1);
  --font-display: "Noto Serif SC", "Songti SC", "STSong", serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  color: var(--navy);
  background-color: var(--cream);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
  transition: var(--transition);
}

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

ul {
  list-style: none;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 96px 0;
}

.section-title {
  font-family: var(--font-display);
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 16px;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: "";
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 48px;
  height: 3px;
  background: var(--gold);
  border-radius: 2px;
}

.section-subtitle {
  color: var(--slate);
  font-size: 1.05rem;
  margin-bottom: 48px;
  max-width: 640px;
}

.text-gold {
  color: var(--gold);
}

/* Header & Nav */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  background: rgba(10, 25, 47, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--lighter-navy);
  transition: var(--transition);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--cream);
}

.logo svg {
  width: 36px;
  height: 36px;
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 8px;
}

.nav-link {
  color: var(--light-slate);
  font-size: 0.95rem;
  padding: 8px 14px;
  border-radius: var(--radius);
}

.nav-link:hover,
.nav-link.active {
  color: var(--gold);
  background: var(--lighter-navy);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--gold);
  transition: var(--transition);
}

.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);
}

/* Hero */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--navy);
  position: relative;
  overflow: hidden;
  padding-top: 72px;
}

.hero::before {
  content: "";
  position: absolute;
  top: -50%;
  right: -20%;
  width: 80%;
  height: 120%;
  background: radial-gradient(circle, rgba(246, 195, 68, 0.08) 0%, transparent 60%);
  pointer-events: none;
}

.hero-content {
  text-align: center;
  max-width: 880px;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

.hero-label {
  display: inline-block;
  color: var(--gold);
  font-size: 0.9rem;
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 24px;
  border: 1px solid var(--gold);
  padding: 6px 16px;
  border-radius: 30px;
}

.hero-title {
  font-family: var(--font-display);
  font-size: 4rem;
  font-weight: 800;
  color: var(--cream);
  line-height: 1.15;
  margin-bottom: 24px;
}

.hero-title span {
  color: var(--gold);
}

.hero-desc {
  font-size: 1.25rem;
  color: var(--slate);
  margin-bottom: 40px;
  max-width: 640px;
  margin-left: auto;
  margin-right: auto;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius);
  cursor: pointer;
  transition: var(--transition);
  border: 1px solid transparent;
  font-family: var(--font-body);
}

.btn-primary {
  background: var(--gold);
  color: var(--navy);
  border-color: var(--gold);
}

.btn-primary:hover {
  background: var(--light-gold);
  border-color: var(--light-gold);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(246, 195, 68, 0.25);
}

.btn-outline {
  background: transparent;
  color: var(--gold);
  border-color: var(--gold);
}

.btn-outline:hover {
  background: rgba(246, 195, 68, 0.1);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 8px 18px;
  font-size: 0.9rem;
}

/* Cards */
.card {
  background: var(--white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: 0 4px 20px var(--shadow-sm);
  transition: var(--transition);
  border: 1px solid rgba(17, 34, 64, 0.06);
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 32px rgba(17, 34, 64, 0.12);
}

.card-body {
  padding: 28px;
}

.card-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 10px;
}

.card-title a:hover {
  color: var(--dark-gold);
}

.card-text {
  color: var(--slate);
  font-size: 0.95rem;
  line-height: 1.7;
}

.card-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 16px;
  font-size: 0.85rem;
  color: var(--slate);
}

/* Tags */
.tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 30px;
  font-size: 0.8rem;
  font-weight: 500;
  background: rgba(246, 195, 68, 0.12);
  color: var(--dark-gold);
}

.tag-outline {
  background: transparent;
  border: 1px solid var(--gold);
  color: var(--gold);
}

/* Expert Grid */
.expert-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.expert-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 32px 24px;
  text-decoration: none;
  color: inherit;
}

.expert-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--light-navy), var(--lighter-navy));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gold);
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 18px;
  border: 2px solid var(--gold);
}

.expert-name {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 8px;
}

.expert-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: center;
  margin-bottom: 12px;
}

.expert-desc {
  font-size: 0.9rem;
  color: var(--slate);
  line-height: 1.6;
}

/* Filter */
.filter-bar {
  display: flex;
  gap: 12px;
  margin-bottom: 40px;
  flex-wrap: wrap;
}

.filter-btn {
  padding: 8px 20px;
  border-radius: 30px;
  border: 1px solid var(--lighter-navy);
  background: var(--white);
  color: var(--navy);
  font-size: 0.95rem;
  cursor: pointer;
  transition: var(--transition);
  font-family: var(--font-body);
}

.filter-btn:hover,
.filter-btn.active {
  background: var(--navy);
  color: var(--gold);
  border-color: var(--navy);
}

/* Article List */
.article-list {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.article-item {
  display: flex;
  gap: 24px;
  align-items: flex-start;
  padding: 28px;
}

.article-number {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--gold);
  line-height: 1;
  min-width: 56px;
}

.article-content {
  flex: 1;
}

.article-title {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 10px;
}

.article-title a:hover {
  color: var(--dark-gold);
}

.article-summary {
  color: var(--slate);
  font-size: 0.95rem;
  line-height: 1.7;
  margin-bottom: 12px;
}

/* Value Section */
.value-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.value-card {
  padding: 40px 32px;
  text-align: center;
}

.value-icon {
  width: 64px;
  height: 64px;
  margin: 0 auto 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(246, 195, 68, 0.12);
  border-radius: 50%;
  color: var(--dark-gold);
}

.value-icon svg {
  width: 32px;
  height: 32px;
}

.value-title {
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--navy);
}

.value-text {
  color: var(--slate);
  font-size: 0.95rem;
}

/* Detail Page */
.detail-hero {
  background: var(--navy);
  padding: 140px 0 80px;
}

.detail-hero-content {
  display: flex;
  gap: 48px;
  align-items: center;
}

.detail-avatar {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--light-navy), var(--lighter-navy));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gold);
  font-family: var(--font-display);
  font-size: 3.5rem;
  font-weight: 700;
  border: 3px solid var(--gold);
  flex-shrink: 0;
}

.detail-info h1 {
  font-family: var(--font-display);
  font-size: 2.75rem;
  color: var(--cream);
  margin-bottom: 16px;
}

.detail-info .tags {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.detail-info p {
  color: var(--slate);
  font-size: 1.1rem;
  max-width: 640px;
}

.content-page {
  background: var(--white);
  border-radius: var(--radius-lg);
  padding: 56px;
  box-shadow: 0 4px 24px var(--shadow-sm);
}

.content-page h1 {
  font-family: var(--font-display);
  font-size: 2.25rem;
  color: var(--navy);
  margin-bottom: 16px;
}

.content-page h2 {
  font-family: var(--font-display);
  font-size: 1.5rem;
  color: var(--navy);
  margin: 40px 0 16px;
}

.content-page h3 {
  font-family: var(--font-display);
  font-size: 1.25rem;
  color: var(--navy);
  margin: 28px 0 12px;
}

.content-page p {
  color: var(--slate);
  margin-bottom: 16px;
  font-size: 1.05rem;
}

.content-page ul {
  list-style: disc;
  padding-left: 24px;
  margin-bottom: 20px;
}

.content-page li {
  color: var(--slate);
  margin-bottom: 8px;
  font-size: 1.05rem;
}

.content-page a {
  color: var(--dark-gold);
  text-decoration: underline;
}

/* Footer */
.footer {
  background: var(--navy);
  color: var(--slate);
  padding: 64px 0 32px;
  border-top: 1px solid var(--lighter-navy);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

.footer-brand .logo {
  margin-bottom: 16px;
}

.footer-brand p {
  font-size: 0.95rem;
  line-height: 1.7;
  max-width: 320px;
}

.footer-title {
  color: var(--cream);
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 20px;
}

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

.footer-links a {
  color: var(--slate);
  font-size: 0.95rem;
}

.footer-links a:hover {
  color: var(--gold);
}

.footer-bottom {
  border-top: 1px solid var(--lighter-navy);
  padding-top: 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 0.9rem;
}

/* Scroll Top */
.scroll-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 44px;
  height: 44px;
  background: var(--gold);
  color: var(--navy);
  border: none;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
  z-index: 999;
  box-shadow: 0 4px 16px rgba(246, 195, 68, 0.3);
}

.scroll-top.visible {
  opacity: 1;
  visibility: visible;
}

.scroll-top:hover {
  transform: translateY(-3px);
}

/* Fade in animation */
.fade-in {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* Responsive */
@media (max-width: 1024px) {
  .expert-grid {
    grid-template-columns: repeat(3, 1fr);
  }

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

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

@media (max-width: 768px) {
  .section {
    padding: 64px 0;
  }

  .hero-title {
    font-size: 2.5rem;
  }

  .hero-desc {
    font-size: 1.05rem;
  }

  .section-title {
    font-size: 1.75rem;
  }

  .nav-menu {
    position: fixed;
    top: 72px;
    left: 0;
    width: 100%;
    flex-direction: column;
    background: var(--navy);
    padding: 16px 24px;
    gap: 4px;
    border-bottom: 1px solid var(--lighter-navy);
    transform: translateY(-150%);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
  }

  .nav-menu.active {
    transform: translateY(0);
    opacity: 1;
    visibility: visible;
  }

  .nav-link {
    width: 100%;
    padding: 12px 16px;
  }

  .nav-toggle {
    display: flex;
  }

  .expert-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
  }

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

  .article-item {
    flex-direction: column;
    gap: 12px;
  }

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

  .detail-hero-content {
    flex-direction: column;
    text-align: center;
  }

  .detail-info h1 {
    font-size: 2rem;
  }

  .detail-info .tags {
    justify-content: center;
  }

  .content-page {
    padding: 32px 24px;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

@media (max-width: 480px) {
  .expert-grid {
    grid-template-columns: 1fr;
  }

  .hero-actions {
    flex-direction: column;
    width: 100%;
  }

  .btn {
    width: 100%;
  }
}