:root {
  --color-bg: #F4F4F4;
  --color-deep: #0A1F3C;
  --color-deep-2: #0C2447;
  --color-gold: #C9A86A;
  --color-red: #B85C3C;
  --color-teal: #1B7F7A;
  --color-sand: #F4F4F4;
  --color-dune: #D9C5A0;
  --color-ink: #333333;
  --color-white: #FFFFFF;
  --color-border: rgba(10, 31, 60, 0.12);
  --font-heading: "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --font-body: "Noto Serif SC", "Songti SC", serif;
  --header-h: 76px;
  --header-h-scroll: 60px;
  --container-w: 1440px;
  --rail-w: 280px;
  --radius: 4px;
  --shadow-card: 0 6px 24px rgba(10, 31, 60, 0.08);
  --transition: 0.3s cubic-bezier(0.2, 0.8, 0.2, 1);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--color-ink);
  background-color: var(--color-bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

a {
  color: var(--color-deep);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

ul,
ol {
  list-style: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-deep);
}

button {
  font-family: var(--font-heading);
  cursor: pointer;
}

:focus-visible {
  outline: 3px solid var(--color-gold);
  outline-offset: 2px;
  border-radius: 2px;
}

.skip-link {
  position: fixed;
  top: -60px;
  left: 16px;
  z-index: 2000;
  background: var(--color-deep);
  color: var(--color-sand);
  padding: 12px 20px;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.875rem;
  border-radius: var(--radius);
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 16px;
  color: var(--color-sand);
}

/* ===== 头部 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: linear-gradient(135deg, rgba(10, 31, 60, 0.92), rgba(12, 36, 71, 0.88));
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(201, 168, 106, 0.3);
  height: var(--header-h);
  transition: height 0.4s cubic-bezier(0.2, 0.8, 0.2, 1), background 0.3s ease;
}

.site-header.is-scrolled {
  height: var(--header-h-scroll);
  background: linear-gradient(135deg, rgba(10, 31, 60, 0.97), rgba(12, 36, 71, 0.95));
}

.header-inner {
  max-width: var(--container-w);
  margin: 0 auto;
  height: 100%;
  padding: 0 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  position: relative;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  flex-shrink: 0;
  color: var(--color-sand);
}

.brand:hover {
  color: var(--color-gold);
}

.brand-mark {
  width: 42px;
  height: 42px;
  border: 1px solid rgba(201, 168, 106, 0.5);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.brand-mark::before {
  content: "";
  position: absolute;
  inset: 4px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, rgba(201, 168, 106, 0.25), transparent 60%);
}

.brand:hover .brand-mark {
  transform: rotate(45deg);
  box-shadow: 0 0 16px rgba(201, 168, 106, 0.4);
}

.brand-mark__dot {
  width: 8px;
  height: 8px;
  background: var(--color-gold);
  border-radius: 50%;
  position: absolute;
  top: 12px;
  right: 9px;
}

.brand-mark__line {
  width: 22px;
  height: 2px;
  background: linear-gradient(90deg, var(--color-gold), transparent);
  position: absolute;
  bottom: 11px;
  left: 8px;
  transform: rotate(-45deg);
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.brand-text__name {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.brand-text__sub {
  font-family: var(--font-body);
  font-size: 0.6875rem;
  letter-spacing: 0.18em;
  color: rgba(201, 168, 106, 0.8);
  margin-top: 2px;
  text-transform: uppercase;
}

/* 导航 */
.site-nav {
  display: flex;
  align-items: center;
  gap: 24px;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-item a {
  display: inline-block;
  padding: 10px 16px;
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: rgba(244, 244, 244, 0.88);
  border-radius: var(--radius);
  border: 1px solid transparent;
  transition: background 0.25s ease, color 0.25s ease, border-color 0.25s ease, transform 0.25s ease;
}

.nav-item a:hover {
  color: var(--color-gold);
  background: rgba(201, 168, 106, 0.1);
  border-color: rgba(201, 168, 106, 0.3);
  transform: translateY(-1px);
}

.nav-item a[aria-current="page"] {
  color: var(--color-gold);
  background: rgba(201, 168, 106, 0.14);
  border-color: rgba(201, 168, 106, 0.5);
  box-shadow: inset 0 -2px 0 var(--color-gold);
}

.nav-aside {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-left: 20px;
  margin-left: 4px;
  border-left: 1px solid rgba(201, 168, 106, 0.3);
  font-family: var(--font-heading);
  font-size: 0.75rem;
  color: rgba(244, 244, 244, 0.6);
}

.nav-aside__text {
  letter-spacing: 0.04em;
}

.nav-aside__link {
  color: var(--color-gold);
  border-bottom: 1px solid rgba(201, 168, 106, 0.4);
  transition: border-color 0.2s ease;
}

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

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  background: transparent;
  border: 1px solid rgba(244, 244, 244, 0.2);
  border-radius: var(--radius);
  padding: 10px;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
}

.nav-toggle__line {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-sand);
  transition: transform 0.3s, opacity 0.2s;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* 进度条 */
.progress-track {
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 3px;
  background: rgba(201, 168, 106, 0.15);
  overflow: hidden;
}

.progress-track__bar {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--color-gold), var(--color-teal));
  transition: width 0.1s linear;
}

/* ===== 页脚 ===== */
.site-footer {
  background: var(--color-deep);
  color: rgba(244, 244, 244, 0.8);
  margin-top: auto;
  border-top: 1px solid rgba(201, 168, 106, 0.3);
  position: relative;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-gold) 0%, var(--color-red) 30%, var(--color-deep) 60%, var(--color-teal) 100%);
  opacity: 0.6;
}

.footer-main {
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 64px 32px 40px;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1.2fr;
  gap: 64px;
}

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

.footer-trust {
  font-size: 0.875rem;
  line-height: 1.8;
  color: rgba(244, 244, 244, 0.62);
  max-width: 320px;
  margin-top: 16px;
}

.footer-heading {
  font-family: var(--font-heading);
  font-size: 0.8125rem;
  letter-spacing: 0.12em;
  color: var(--color-gold);
  margin-bottom: 20px;
  text-transform: uppercase;
  position: relative;
  padding-bottom: 8px;
}

.footer-heading::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 28px;
  height: 2px;
  background: var(--color-gold);
  opacity: 0.6;
}

.footer-link-list,
.footer-contact-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.footer-link-list a,
.footer-contact-list a {
  color: rgba(244, 244, 244, 0.78);
  font-family: var(--font-heading);
  font-size: 0.875rem;
  letter-spacing: 0.04em;
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.footer-link-list a:hover,
.footer-contact-list a:hover {
  color: var(--color-gold);
  padding-left: 4px;
}

.footer-contact-list li {
  font-size: 0.875rem;
  color: rgba(244, 244, 244, 0.62);
}

.footer-note {
  margin-top: 16px;
  font-size: 0.75rem;
  color: rgba(244, 244, 244, 0.45);
  line-height: 1.7;
  border-left: 2px solid var(--color-teal);
  padding-left: 12px;
}

.footer-bottom {
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 20px 32px;
  border-top: 1px solid rgba(244, 244, 244, 0.1);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px 24px;
  font-size: 0.8125rem;
  color: rgba(244, 244, 244, 0.5);
  font-family: var(--font-heading);
}

.footer-icp {
  letter-spacing: 0.04em;
}

/* ===== 布局系统 ===== */
.page-shell {
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 0 32px;
  display: grid;
  grid-template-columns: var(--rail-w) 1fr;
  gap: 48px;
  flex: 1;
  width: 100%;
}

.content-stage {
  min-width: 0;
  padding: 64px 0 96px;
}

.stage-header {
  margin-bottom: 56px;
  padding: 40px 0;
  border-bottom: 1px solid var(--color-border);
  position: relative;
}

.stage-header::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -1px;
  width: 86px;
  height: 3px;
  background: linear-gradient(90deg, var(--color-gold), rgba(201, 168, 106, 0.1));
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-gold);
  margin-bottom: 20px;
}

.section-tag::before {
  content: "";
  width: 28px;
  height: 3px;
  background: var(--color-gold);
  transform: skewX(-20deg);
}

.stage-title {
  font-size: clamp(1.5rem, 3vw, 3rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: 0.02em;
  margin-bottom: 16px;
  max-width: 900px;
}

.stage-lede {
  font-size: 1rem;
  line-height: 1.9;
  color: var(--color-ink);
  opacity: 0.8;
  max-width: 720px;
}

.section-label {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-deep);
  margin: 48px 0 24px;
}

.section-label::before {
  content: "";
  display: inline-block;
  width: 4px;
  height: 18px;
  background: var(--color-gold);
  transform: skewX(-15deg);
  border-radius: 1px 0 0 1px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-family: var(--font-heading);
  font-size: 0.8125rem;
  color: rgba(10, 31, 60, 0.6);
  margin-bottom: 40px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-border);
}

.breadcrumb ol {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.breadcrumb li {
  display: flex;
  align-items: center;
  gap: 8px;
}

.breadcrumb li:not(:last-child)::after {
  content: "›";
  color: rgba(10, 31, 60, 0.35);
}

.breadcrumb a {
  color: var(--color-teal);
}

.breadcrumb a:hover {
  color: var(--color-red);
}

/* ===== 卡片与组件 ===== */
.grid-card {
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid rgba(10, 31, 60, 0.08);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow-card);
  transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s;
  height: 100%;
  display: flex;
  flex-direction: column;
}

.grid-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 36px rgba(10, 31, 60, 0.14);
  background: rgba(255, 255, 255, 0.95);
}

.grid-card__title {
  font-family: var(--font-heading);
  font-size: 1.125rem;
  color: var(--color-deep);
  margin-bottom: 8px;
}

.grid-card__text {
  font-size: 0.875rem;
  line-height: 1.8;
  color: var(--color-ink);
  opacity: 0.78;
  flex: 1;
}

.tag {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  border-radius: 999px;
  line-height: 1.5;
  width: fit-content;
}

.tag--gold {
  background: rgba(201, 168, 106, 0.2);
  color: #8a6b30;
  border: 1px solid rgba(201, 168, 106, 0.5);
}

.tag--red {
  background: rgba(184, 92, 60, 0.12);
  color: var(--color-red);
  border: 1px solid rgba(184, 92, 60, 0.3);
}

.tag--teal {
  background: rgba(27, 127, 122, 0.12);
  color: var(--color-teal);
  border: 1px solid rgba(27, 127, 122, 0.3);
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 24px;
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  border-radius: var(--radius);
  transition: background 0.3s, color 0.3s, border-color 0.3s, transform 0.2s;
  text-align: center;
}

.btn:hover {
  transform: translateY(-2px);
}

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

.btn--primary:hover {
  background: #d8b87e;
  border-color: #d8b87e;
  color: var(--color-deep);
}

.btn--ghost {
  background: transparent;
  color: var(--color-deep);
  border: 1px solid rgba(10, 31, 60, 0.4);
}

.btn--ghost:hover {
  border-color: var(--color-deep);
  background: rgba(10, 31, 60, 0.05);
}

/* 图片容器 */
.img-frame {
  position: relative;
  background: linear-gradient(135deg, var(--color-dune), rgba(216, 184, 126, 0.2), var(--color-deep));
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-card);
}

.img-frame::after {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, rgba(244, 244, 244, 0), rgba(201, 168, 106, 0.15));
  pointer-events: none;
}

.img-frame--landscape {
  aspect-ratio: 16 / 9;
  width: 100%;
}

.img-frame--portrait {
  aspect-ratio: 3 / 4;
  max-width: 320px;
}

.img-frame--arch {
  aspect-ratio: 3 / 4;
  width: 100%;
}

/* 间距工具 */
.section-gap {
  margin-top: 64px;
}

.grid-2col {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.grid-3col {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

/* 返回顶部 */
.back-to-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 900;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px solid rgba(201, 168, 106, 0.5);
  background: var(--color-deep);
  color: var(--color-gold);
  font-size: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(16px);
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s, background 0.3s;
  box-shadow: 0 4px 20px rgba(10, 31, 60, 0.3);
}

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

.back-to-top:hover {
  background: var(--color-gold);
  color: var(--color-deep);
}

/* 显现 */
[data-reveal] {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s cubic-bezier(0.2, 0.8, 0.2, 1), transform 0.6s cubic-bezier(0.2, 0.8, 0.2, 1);
}

[data-reveal].is-visible {
  opacity: 1;
  transform: none;
}

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .header-inner,
  .page-shell,
  .footer-main,
  .footer-bottom {
    padding-left: 24px;
    padding-right: 24px;
  }

  .page-shell {
    grid-template-columns: 1fr;
  }

  .content-stage {
    padding-top: 40px;
  }

  .nav-aside {
    display: none;
  }
}

@media (max-width: 768px) {
  :root {
    --header-h: 64px;
  }

  .nav-toggle {
    display: flex;
    z-index: 1101;
  }

  .site-nav {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: min(320px, 88vw);
    background: var(--color-deep);
    border-left: 1px solid rgba(201, 168, 106, 0.3);
    flex-direction: column;
    justify-content: flex-start;
    align-items: flex-start;
    padding: 96px 32px 48px;
    transform: translateX(100%);
    transition: transform 0.4s cubic-bezier(0.2, 0.8, 0.2, 1);
    box-shadow: -20px 0 48px rgba(10, 31, 60, 0.4);
    overflow-y: auto;
  }

  .site-nav[data-open="true"] {
    transform: translateX(0);
  }

  .nav-list {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
    width: 100%;
  }

  .nav-item {
    width: 100%;
  }

  .nav-item a {
    display: block;
    width: 100%;
    padding: 14px 16px;
    font-size: 1rem;
    border: 1px solid rgba(244, 244, 244, 0.08);
    background: rgba(244, 244, 244, 0.03);
  }

  .nav-item a[aria-current="page"] {
    box-shadow: inset 3px 0 0 var(--color-gold);
  }

  .nav-aside {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    border-left: none;
    border-top: 1px solid rgba(201, 168, 106, 0.3);
    padding: 24px 0 0;
    margin: 24px 0 0;
  }

  .header-inner {
    padding: 0 20px;
  }

  .page-shell {
    padding: 0 20px;
  }

  .footer-main {
    grid-template-columns: 1fr;
    gap: 40px;
    padding: 48px 20px 32px;
  }

  .footer-bottom {
    flex-direction: column;
    padding: 20px;
  }

  .grid-3col,
  .grid-2col {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .stage-header {
    padding: 24px 0 32px;
    margin-bottom: 32px;
  }

  .back-to-top {
    right: 16px;
    bottom: 16px;
    width: 44px;
    height: 44px;
  }
}

@media (max-width: 480px) {
  .brand-text__sub {
    display: none;
  }

  .brand-mark {
    width: 36px;
    height: 36px;
  }

  .grid-card {
    padding: 20px;
  }
}

@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: 0 !important;
  }

  [data-reveal] {
    opacity: 1;
    transform: none;
  }

  .back-to-top {
    transition: none;
  }
}