/*
 * 医美填充剂研究系列 - 主样式文件
 * Clean & Professional Design
 * BCC Style - Simplified
 */

/* ========== CSS Variables ========== */
:root {
  /* 主色调 - 从参考网站提取 */
  --primary-color: #0d2c54;
  --primary-hover: #1a4a8c;
  --accent-color: #f5a623;
  --navy-color: #0a2240;

  /* 背景色 - 简洁干净 */
  --bg-color: #f8f9fa;
  --bg-secondary: #ffffff;
  --bg-tertiary: #f1f3f5;
  --bg-dark: #0d2c54;

  /* 文字色 */
  --text-primary: #0d2c54;
  --text-secondary: #5a6a7a;
  --text-light: #8a9aaa;
  --text-white: #ffffff;

  /* 边框色 */
  --border-color: #e5e7eb;
  --border-light: #f0f2f5;

  /* 阴影 - 柔和不花哨 */
  --shadow-sm: 0 1px 3px rgba(13, 44, 84, 0.08);
  --shadow-md: 0 4px 12px rgba(13, 44, 84, 0.1);
  --shadow-lg: 0 8px 24px rgba(13, 44, 84, 0.12);
  --shadow-xl: 0 16px 48px rgba(13, 44, 84, 0.15);

  /* 圆角 */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;

  /* 过渡 */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;

  /* 字体 */
  --font-primary: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

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

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

body {
  font-family: var(--font-primary);
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

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

ul, ol {
  list-style: none;
}

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

button {
  cursor: pointer;
  border: none;
  background: none;
  font-family: inherit;
}

/* ========== Typography ========== */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.3;
  color: var(--text-primary);
}

h1 { font-size: 2.25rem; font-weight: 700; }
h2 { font-size: 1.75rem; font-weight: 600; }
h3 { font-size: 1.35rem; font-weight: 600; }
h4 { font-size: 1.15rem; font-weight: 600; }

p {
  margin-bottom: 1rem;
  color: var(--text-secondary);
}

.text-primary { color: var(--primary-color); }
.text-accent { color: var(--accent-color); }
.text-muted { color: var(--text-light); }
.text-center { text-align: center; }
.text-white { color: var(--text-white); }

/* ========== Layout ========== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.section {
  padding: 4rem 0;
}

.section-header {
  text-align: center;
  margin-bottom: 2.5rem;
}

.section-header h2 {
  margin-bottom: 0.75rem;
  position: relative;
  display: inline-block;
}

.section-header h2::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 50%;
  transform: translateX(-50%);
  width: 48px;
  height: 3px;
  background: var(--accent-color);
}

.section-header p {
  max-width: 600px;
  margin: 1rem auto 0;
  font-size: 1rem;
}

/* ========== Header & Navigation ========== */
.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

/* Logo Design */
.logo {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text-primary);
}

.logo-icon {
  width: 40px;
  height: 40px;
  background: var(--primary-color);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.1rem;
}

.logo-text {
  display: flex;
  flex-direction: column;
}

.logo-text .brand {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.2;
}

.logo-text .tagline {
  font-size: 0.65rem;
  color: var(--accent-color);
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* Nav Links */
.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.nav-links a {
  padding: 0.5rem 1rem;
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-md);
}

.nav-links a:hover {
  color: var(--primary-color);
  background: var(--bg-tertiary);
}

.nav-links a.active {
  color: var(--primary-color);
  background: rgba(13, 44, 84, 0.05);
}

/* Header CTA Button */
.nav-cta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-btn {
  padding: 0.5rem 1rem;
  font-size: 0.85rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.nav-btn-primary {
  background: var(--primary-color);
  color: white;
}

.nav-btn-primary:hover {
  background: var(--primary-hover);
}

/* Mobile Toggle */
.mobile-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 0.5rem;
}

.mobile-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 1px;
  transition: all var(--transition-fast);
}

/* ========== Hero Section ========== */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  padding-top: 64px;
  background: var(--bg-secondary);
  position: relative;
}

.hero-content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 0.4rem 1rem;
  background: var(--bg-tertiary);
  border-radius: var(--radius-full);
  font-size: 0.85rem;
  font-weight: 500;
  margin-bottom: 1.5rem;
}

.hero-badge .dot {
  width: 6px;
  height: 6px;
  background: var(--accent-color);
  border-radius: 50%;
}

.hero h1 {
  font-size: 2.25rem;
  margin-bottom: 1rem;
  line-height: 1.3;
}

.hero-subtitle {
  font-size: 1.05rem;
  max-width: 600px;
  margin: 0 auto 2rem;
  line-height: 1.7;
}

.hero-stats {
  display: flex;
  justify-content: center;
  gap: 3rem;
  margin-top: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
}

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

.stat-number {
  font-size: 2rem;
  font-weight: 700;
  display: block;
  color: var(--primary-color);
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 0.25rem;
}

.hero-buttons {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 2rem;
}

/* ========== Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  border-radius: var(--radius-md);
  font-size: 0.95rem;
  font-weight: 600;
  transition: all var(--transition-normal);
  cursor: pointer;
  white-space: nowrap;
}

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

.btn-primary:hover {
  background: var(--primary-hover);
  transform: translateY(-1px);
}

.btn-secondary {
  background: transparent;
  color: var(--primary-color);
  border: 1px solid var(--border-color);
}

.btn-secondary:hover {
  background: var(--bg-tertiary);
}

/* ========== Cards ========== */
.card {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  overflow: hidden;
  transition: all var(--transition-normal);
  border: 1px solid var(--border-color);
}

.card:hover {
  box-shadow: var(--shadow-lg);
}

/* ========== Report Cards ========== */
.report-card {
  position: relative;
  border: 1px solid var(--border-color);
}

.report-card .card-header {
  background: var(--primary-color);
  color: white;
  padding: 1rem 1.25rem;
  border: none;
}

.report-card .report-number {
  position: absolute;
  top: -10px;
  right: 1rem;
  width: 32px;
  height: 32px;
  background: var(--accent-color);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.8rem;
  font-weight: 700;
  z-index: 1;
}

.report-card .card-body {
  padding: 1.5rem;
}

.report-card .report-title {
  font-size: 1.05rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  font-weight: 600;
}

.report-card .report-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 0.75rem;
  line-height: 1.6;
}

.report-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.8rem;
  color: var(--text-light);
}

.report-meta span {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.report-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.75rem;
}

.tag {
  padding: 0.2rem 0.6rem;
  background: var(--bg-tertiary);
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.tag-primary {
  background: rgba(13, 44, 84, 0.08);
  color: var(--primary-color);
}

.tag-accent {
  background: rgba(201, 162, 39, 0.1);
  color: var(--accent-color);
}

/* ========== Grid Layouts ========== */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
}

/* ========== Features Section ========== */
.features {
  background: var(--bg-secondary);
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.25rem;
}

.feature-card {
  text-align: center;
  padding: 1.5rem 1.25rem;
  background: var(--bg-color);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-color);
  transition: all var(--transition-normal);
}

.feature-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  border-color: var(--accent-color);
}

.feature-icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 1rem;
  background: var(--primary-color);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  color: white;
}

.feature-card h4 {
  margin-bottom: 0.5rem;
  color: var(--text-primary);
  font-size: 0.95rem;
}

.feature-card p {
  font-size: 0.85rem;
  margin-bottom: 0;
  color: var(--text-secondary);
}

/* ========== Company Comparison ========== */
.comparison-section {
  background: var(--bg-tertiary);
}

.comparison-table {
  width: 100%;
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-color);
}

.comparison-table table {
  width: 100%;
  border-collapse: collapse;
}

.comparison-table th,
.comparison-table td {
  padding: 0.85rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-light);
}

.comparison-table th {
  background: var(--primary-color);
  color: white;
  font-weight: 600;
  white-space: nowrap;
}

.comparison-table tr:last-child td {
  border-bottom: none;
}

.comparison-table tr:hover td {
  background: var(--bg-tertiary);
}

/* ========== Timeline ========== */
.timeline {
  position: relative;
  padding-left: 1.5rem;
}

.timeline::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border-color);
}

.timeline-item {
  position: relative;
  padding-bottom: 1.5rem;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -1.5rem;
  top: 0.25rem;
  width: 8px;
  height: 8px;
  background: var(--accent-color);
  border-radius: 50%;
  transform: translateX(-3px);
}

.timeline-item h4 {
  color: var(--primary-color);
  margin-bottom: 0.25rem;
  font-size: 1rem;
}

.timeline-item .date {
  font-size: 0.8rem;
  color: var(--accent-color);
  margin-bottom: 0.25rem;
  font-weight: 500;
}

/* ========== Footer ========== */
.footer {
  background: var(--bg-dark);
  color: white;
  padding: 3rem 0 1.5rem;
}

.footer-main {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

/* Footer Brand */
.footer-brand {
  padding-right: 1.5rem;
}

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

.footer-brand .logo-text .brand {
  color: white;
}

.footer-brand .logo-text .tagline {
  color: var(--accent-color);
}

.footer-brand p {
  color: rgba(255, 255, 255, 0.6);
  margin-top: 0.75rem;
  font-size: 0.9rem;
  line-height: 1.6;
}

.footer-social {
  display: flex;
  gap: 0.5rem;
  margin-top: 1rem;
}

.footer-social a {
  width: 36px;
  height: 36px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255, 255, 255, 0.7);
  font-size: 0.9rem;
  transition: all var(--transition-fast);
}

.footer-social a:hover {
  background: var(--accent-color);
  color: white;
}

/* Footer Columns */
.footer h5 {
  color: white;
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.footer-links li {
  margin-bottom: 0.5rem;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

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

.footer-links a::before {
  content: '';
  width: 4px;
  height: 4px;
  background: var(--accent-color);
  border-radius: 50%;
  opacity: 0;
  transition: all var(--transition-fast);
}

.footer-links a:hover::before {
  opacity: 1;
}

/* Footer Contact */
.footer-contact {
  color: rgba(255, 255, 255, 0.6);
  font-size: 0.85rem;
}

.footer-contact li {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}

.footer-contact .icon {
  width: 28px;
  height: 28px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

/* Footer Bottom */
.footer-bottom {
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: rgba(255, 255, 255, 0.4);
}

.footer-bottom-links {
  display: flex;
  gap: 1.5rem;
}

.footer-bottom-links a {
  color: rgba(255, 255, 255, 0.4);
}

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

/* ICP备案号样式 */
.footer-icp {
  text-align: center;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.4);
}

.footer-icp a {
  color: rgba(255, 255, 255, 0.4);
}

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

/* ========== Animations ========== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(15px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fadeInUp {
  animation: fadeInUp 0.5s ease forwards;
}

/* ========== Utility Classes ========== */
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

.p-1 { padding: 0.5rem; }
.p-2 { padding: 1rem; }
.p-3 { padding: 1.5rem; }
.p-4 { padding: 2rem; }

.flex { display: flex; }
.flex-center { align-items: center; justify-content: center; }
.flex-between { align-items: center; justify-content: space-between; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.gap-3 { gap: 1.5rem; }

/* ========== Custom Scrollbar ========== */
::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: var(--bg-tertiary);
}

::-webkit-scrollbar-thumb {
  background: var(--primary-color);
  border-radius: 3px;
}

/* ========== Responsive Design ========== */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-main { grid-template-columns: 1fr 1fr; gap: 1.5rem; }
  .footer-brand { padding-right: 0; grid-column: span 2; }
}

@media (max-width: 768px) {
  h1 { font-size: 1.75rem; }
  h2 { font-size: 1.35rem; }

  .nav-links {
    position: fixed;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--bg-secondary);
    flex-direction: column;
    padding: 1rem;
    gap: 0.25rem;
    box-shadow: var(--shadow-md);
    transform: translateY(-100%);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
  }

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

  .nav-links a {
    width: 100%;
    padding: 0.75rem 1rem;
  }

  .nav-cta {
    display: none;
  }

  .mobile-toggle {
    display: flex;
  }

  .hero { padding-top: 80px; min-height: auto; padding-bottom: 3rem; }
  .hero h1 { font-size: 1.75rem; }
  .hero-subtitle { font-size: 0.95rem; }
  .hero-stats { gap: 1.5rem; flex-wrap: wrap; }
  .stat-number { font-size: 1.5rem; }
  .hero-buttons { flex-direction: column; align-items: center; }

  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .feature-grid { grid-template-columns: 1fr; }

  .section { padding: 2.5rem 0; }

  .comparison-table {
    overflow-x: auto;
  }

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

  .footer-brand {
    grid-column: span 1;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 0.75rem;
    text-align: center;
  }

  .footer-bottom-links {
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
  }
}

/* ========== Print Styles ========== */
@media print {
  .header, .hero-buttons, .footer {
    display: none;
  }

  .hero {
    padding-top: 0;
    min-height: auto;
    background: white;
  }

  .card {
    break-inside: avoid;
    box-shadow: none;
    border: 1px solid #ddd;
  }
}