/* ========== 1. Reset ========== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

/* ========== 2. CSS Variables ========== */
:root {
  /* 色彩系统 */
  --color-primary: #0A1F44;
  --color-gold: #D4AF37;
  --color-gold-light: #F1D27A;
  --color-red: #E63946;
  --color-bg-light: #F5F7FA;
  --color-white: #FFFFFF;
  --color-text: #1E2A38;
  --color-text-secondary: #5A6B7B;
  --color-border: #D8DEE9;
  --color-success: #2E8B57;
  --gradient-gold: linear-gradient(135deg, #D4AF37, #F1D27A);

  /* 字体系统 */
  --font-heading: "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Source Han Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-index: "Roboto Mono", "SF Mono", "Cascadia Mono", monospace;

  /* 布局 */
  --container-width: 1200px;
  --container-padding: 24px;
  --radius: 4px;

  /* 间距 */
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 40px;
  --space-xl: 64px;
  --space-2xl: 96px;

  /* 动效 */
  --transition: 0.25s ease;
  --shadow-card: 0 4px 20px rgba(10, 31, 68, 0.08);
  --shadow-header: 0 2px 16px rgba(10, 31, 68, 0.06);
}

/* ========== 3. Base Typography ========== */
html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 900;
  line-height: 1.2;
  color: var(--color-primary);
  letter-spacing: 0.02em;
}

h1 { font-size: clamp(32px, 5vw, 48px); }
h2 { font-size: clamp(26px, 4vw, 36px); }
h3 { font-size: clamp(20px, 3vw, 24px); }
h4 { font-size: 18px; }

p {
  margin-bottom: 1em;
}

a {
  color: var(--color-primary);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

a:hover {
  color: var(--color-red);
  text-decoration-color: var(--color-red);
}

ul, ol {
  list-style-position: inside;
}

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

::selection {
  background: var(--color-gold);
  color: var(--color-primary);
}

/* ========== 4. Accessibility ========== */
.skip-link {
  position: absolute;
  top: -100px;
  left: 16px;
  z-index: 1000;
  padding: 10px 20px;
  background: var(--color-primary);
  color: var(--color-gold);
  font-size: 14px;
  font-weight: 700;
  border-radius: var(--radius);
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 8px;
  outline: 2px solid var(--color-gold);
  outline-offset: 2px;
}

:focus-visible {
  outline: 2px solid var(--color-gold);
  outline-offset: 2px;
  border-radius: 2px;
}

/* ========== 5. Layout Utilities ========== */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

.section {
  padding: var(--space-xl) 0;
}

.section-bg-light {
  background: var(--color-bg-light);
}

/* ========== 6. Buttons ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 24px;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 14px;
  line-height: 1.4;
  letter-spacing: 0.05em;
  text-decoration: none;
  border: 2px solid transparent;
  border-radius: var(--radius);
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition), box-shadow var(--transition);
}

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

.btn-gold:hover {
  background: var(--color-primary);
  color: var(--color-gold);
  border-color: var(--color-primary);
  box-shadow: 0 4px 16px rgba(10, 31, 68, 0.2);
}

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

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

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

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

/* ========== 7. Header ========== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  box-shadow: var(--shadow-header);
}

/* 顶部深蓝信息条 */
.header-topbar {
  position: relative;
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.88);
  font-family: var(--font-index);
  font-size: 12px;
  letter-spacing: 0.04em;
  border-bottom: 2px solid var(--color-gold);
}

.header-topbar-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  min-height: 36px;
  gap: 24px;
}

.topbar-statement {
  margin: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  display: flex;
  align-items: center;
  gap: 8px;
}

.topbar-live-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  background: var(--color-red);
  border-radius: 50%;
  flex-shrink: 0;
  animation: live-pulse 2s ease-in-out infinite;
  box-shadow: 0 0 0 3px rgba(230, 57, 70, 0.25);
}

@keyframes live-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.45; }
}

.topbar-contact {
  color: var(--color-gold);
  text-decoration: none;
  font-weight: 700;
  white-space: nowrap;
  transition: color var(--transition);
}

.topbar-contact:hover {
  color: var(--color-white);
  text-decoration: none;
}

/* 主头部 */
.header-main {
  background: var(--color-white);
}

.header-main-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  min-height: 72px;
}

/* 品牌 */
.brand-logo {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  text-decoration: none;
  gap: 10px;
}

.brand-mark {
  display: inline-block;
  width: 24px;
  height: 24px;
  background: var(--gradient-gold);
  clip-path: polygon(50% 0%, 100% 38%, 82% 100%, 18% 100%, 0% 38%);
  transition: transform var(--transition);
}

.brand-logo:hover .brand-mark {
  transform: rotate(8deg) scale(1.08);
}

.brand-name {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 21px;
  color: var(--color-primary);
  letter-spacing: 0.06em;
  line-height: 1;
  white-space: nowrap;
}

.brand-name em {
  font-style: normal;
  font-weight: 700;
  font-size: 0.82em;
  color: var(--color-gold);
  margin-left: 3px;
}

/* 导航 */
.main-nav {
  margin-left: auto;
}

.nav-list {
  display: flex;
  list-style: none;
  align-items: center;
  gap: 2px;
  margin: 0;
  padding: 0;
}

.nav-item {
  margin: 0;
}

.nav-link {
  display: inline-block;
  padding: 10px 14px;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 15px;
  color: var(--color-text);
  text-decoration: none;
  letter-spacing: 0.03em;
  border-bottom: 2px solid transparent;
  transition: color var(--transition), border-color var(--transition);
  white-space: nowrap;
}

.nav-link:hover {
  color: var(--color-red);
  border-bottom-color: var(--color-red);
  text-decoration: none;
}

.nav-link[aria-current="page"] {
  color: var(--color-primary);
  border-bottom-color: var(--color-gold);
}

/* CTA */
.header-cta {
  flex-shrink: 0;
  gap: 8px;
}

.header-cta .btn-icon {
  font-size: 14px;
  line-height: 1;
}

/* 移动导航按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  padding: 10px;
  margin-left: auto;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color var(--transition);
  flex-shrink: 0;
}

.nav-toggle:hover {
  border-color: var(--color-gold);
}

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

.nav-toggle:hover .nav-toggle-line {
  background: var(--color-gold);
}

/* ========== 8. Footer ========== */
.site-footer {
  position: relative;
  overflow: hidden;
  background: var(--color-primary);
  color: rgba(255, 255, 255, 0.82);
  border-top: 4px solid var(--color-gold);
}

.site-footer::before {
  content: '';
  position: absolute;
  bottom: -120px;
  right: -80px;
  width: 360px;
  height: 360px;
  background: repeating-linear-gradient(
    45deg,
    transparent 0px,
    rgba(212, 175, 55, 0.05) 2px,
    transparent 4px,
    transparent 14px
  );
  pointer-events: none;
}

.footer-main {
  position: relative;
  z-index: 1;
  padding: 56px 0 40px;
  background: linear-gradient(180deg, rgba(212,175,55,0.04) 0%, transparent 140px);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 0.9fr 1.2fr;
  gap: 48px;
}

/* 品牌列 */
.footer-brand-col {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
}

.footer-brand-mark {
  display: inline-block;
  width: 22px;
  height: 22px;
  background: var(--gradient-gold);
  clip-path: polygon(50% 0%, 100% 38%, 82% 100%, 18% 100%, 0% 38%);
  flex-shrink: 0;
}

.footer-brand-name {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 22px;
  color: var(--color-white);
  letter-spacing: 0.06em;
  line-height: 1;
}

.footer-brand-name em {
  font-style: normal;
  font-weight: 700;
  font-size: 0.82em;
  color: var(--color-gold);
  margin-left: 3px;
}

.footer-statement {
  color: rgba(255, 255, 255, 0.6);
  font-size: 14px;
  line-height: 1.7;
  margin: 0;
  max-width: 280px;
}

/* 栏目列 */
.footer-col-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.06em;
  color: var(--color-gold);
  padding-bottom: 10px;
  margin-bottom: 18px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  position: relative;
}

.footer-col-title::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 28px;
  height: 1px;
  background: var(--color-gold);
}

.footer-nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer-nav-list li {
  margin-bottom: 10px;
}

.footer-nav-list a {
  color: rgba(255, 255, 255, 0.72);
  text-decoration: none;
  font-size: 14px;
  transition: color var(--transition), padding-left var(--transition);
}

.footer-nav-list a:hover {
  color: var(--color-gold);
  padding-left: 4px;
  text-decoration: none;
}

/* 联系方式列 */
.footer-contact-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.footer-contact-item {
  display: flex;
  padding: 8px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  gap: 10px;
  font-size: 14px;
  line-height: 1.6;
}

.footer-contact-item:last-child {
  border-bottom: none;
}

.contact-label {
  display: inline-block;
  min-width: 32px;
  flex-shrink: 0;
  font-family: var(--font-index);
  font-size: 12px;
  color: var(--color-gold);
  letter-spacing: 0.04em;
  padding-top: 2px;
}

.contact-value {
  color: rgba(255, 255, 255, 0.72);
}

/* 底栏 */
.footer-bottom {
  position: relative;
  z-index: 1;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 16px 0;
  background: rgba(0, 0, 0, 0.12);
}

.footer-bottom-inner {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  font-family: var(--font-index);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.46);
  letter-spacing: 0.04em;
}

.footer-icp,
.footer-domain {
  margin: 0;
}

/* 返回顶部 */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--color-primary);
  color: var(--color-gold);
  border: 2px solid var(--color-gold);
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--transition), transform var(--transition), background var(--transition), color var(--transition);
  z-index: 99;
  box-shadow: 0 4px 16px rgba(10, 31, 68, 0.3);
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover,
.back-to-top:focus-visible {
  background: var(--color-gold);
  color: var(--color-primary);
}

/* ========== 9. Breadcrumb ========== */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  margin: 24px 0;
  padding: 0;
  font-family: var(--font-index);
  font-size: 13px;
  letter-spacing: 0.04em;
}

.breadcrumb-item {
  margin: 0;
}

.breadcrumb-item + .breadcrumb-item::before {
  content: '⁄';
  margin: 0 10px;
  color: var(--color-gold);
}

.breadcrumb-link {
  color: var(--color-text-secondary);
  text-decoration: none;
}

.breadcrumb-link:hover {
  color: var(--color-red);
  text-decoration: none;
}

.breadcrumb-item.is-active {
  color: var(--color-primary);
  font-weight: 700;
}

/* ========== 10. Cards ========== */
.card {
  position: relative;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-md);
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}

.card:hover {
  border-color: var(--color-gold);
  box-shadow: var(--shadow-card);
}

.card-title {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 20px;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.card-text {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 0;
}

.card-index {
  font-family: var(--font-index);
  font-size: 12px;
  color: var(--color-gold);
  letter-spacing: 0.06em;
  display: block;
  margin-bottom: 8px;
}

/* ========== 11. Tags ========== */
.tag {
  display: inline-block;
  padding: 4px 12px;
  font-family: var(--font-index);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  border-radius: 2px;
  background: var(--color-bg-light);
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  white-space: nowrap;
}

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

.tag-red {
  background: var(--color-red);
  border-color: var(--color-red);
  color: var(--color-white);
}

.tag-blue {
  background: var(--color-white);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

/* ========== 12. Grids ========== */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
}

/* ========== 13. Image Frame ========== */
.image-frame {
  position: relative;
  overflow: hidden;
  background: var(--color-bg-light);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}

.image-frame::before {
  content: '';
  display: block;
  padding-top: 62.5%;
}

.image-frame img,
.image-frame > img {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.image-frame:hover img {
  transform: scale(1.03);
}

.image-frame-wide::before {
  padding-top: 40%;
}

.image-frame-square::before {
  padding-top: 100%;
}

/* ========== 14. Divider ========== */
.divider {
  height: 3px;
  border: none;
  background: linear-gradient(90deg, var(--color-gold), var(--color-gold-light), transparent);
  margin: var(--space-lg) 0;
}

/* ========== 15. Index Number ========== */
.index-number {
  font-family: var(--font-index);
  font-weight: 700;
  font-size: 14px;
  color: var(--color-gold);
  letter-spacing: 0.08em;
}

/* ========== 16. Collect Button ========== */
.collect-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: var(--color-bg-light);
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  font-size: 17px;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition), transform var(--transition);
}

.collect-btn:hover {
  border-color: var(--color-gold);
  color: var(--color-gold);
  transform: scale(1.06);
}

.collect-btn[data-saved] {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-gold);
}

/* ========== 17. Responsive ========== */
@media (min-width: 900px) {
  .nav-toggle {
    display: none;
  }

  .main-nav {
    display: block;
  }
}

@media (max-width: 899px) {
  .header-main {
    position: relative;
  }

  .header-main-inner {
    min-height: 60px;
    gap: 12px;
  }

  .brand-name {
    font-size: 18px;
  }

  .brand-mark {
    width: 20px;
    height: 20px;
  }

  .nav-toggle {
    display: flex;
  }

  .main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-white);
    border-top: 1px solid var(--color-border);
    border-bottom: 3px solid var(--color-primary);
    box-shadow: 0 12px 24px rgba(10, 31, 68, 0.12);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    margin: 0;
  }

  .main-nav[data-open] {
    max-height: 460px;
    overflow-y: auto;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 0;
  }

  .nav-item {
    width: 100%;
  }

  .nav-link {
    display: block;
    padding: 14px var(--container-padding);
    border-bottom: 1px solid var(--color-border);
    font-size: 16px;
    white-space: normal;
  }
}

@media (max-width: 767px) {
  .container-topbar-inner,
  .header-topbar-inner {
    gap: 12px;
  }

  .header-topbar {
    font-size: 11px;
  }

  .topbar-statement {
    max-width: 100%;
  }

  .topbar-contact {
    display: none;
  }

  .header-main-inner {
    gap: 10px;
  }

  .header-cta .btn-text {
    display: none;
  }

  .header-cta {
    width: 42px;
    height: 42px;
    padding: 0;
    font-size: 16px;
  }

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

  .footer-main {
    padding: 40px 0 32px;
  }

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

  .footer-bottom-inner {
    flex-direction: column;
    text-align: center;
    gap: 6px;
  }

  .back-to-top {
    bottom: 16px;
    right: 16px;
    width: 40px;
    height: 40px;
  }
}

@media (min-width: 768px) and (max-width: 1023px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 36px;
  }

  .grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }

  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ========== 18. Reduced Motion ========== */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0s !important;
  }

  .main-nav {
    transition: none !important;
  }

  .topbar-live-dot {
    animation: none !important;
  }

  .image-frame img {
    transition: none !important;
  }
}