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

:root {
  --color-navy: #0B1E33;
  --color-navy-deep: #070F1D;
  --color-navy-panel: #0F2440;
  --color-navy-border: #2C3E50;
  --color-gold: #C9A227;
  --color-gold-light: #E8C55A;
  --color-gold-deep: #8F7418;
  --color-red: #E5484D;
  --color-red-deep: #B23B3F;
  --color-cream: #F5F3EC;
  --color-cream-dim: #D9D5C8;
  --color-text-dark: #1A1A1A;
  --color-text-light: #F5F3EC;
  --color-text-muted: #9AB0C5;
  --color-blue: #3B82F6;
  --color-green: #10B981;
  --color-chart-red: #EF4444;
  --color-white: #FFFFFF;

  --font-heading: "PingFang SC", "Source Han Sans SC", "Hiragino Sans GB", "MicroSoft YaHei", "Helvetica Neue", sans-serif;
  --font-body: "PingFang SC", "MicroSoft YaHei", "Arial", "Helvetica Neue", sans-serif;
  --font-data: "Roboto Mono", "SF Mono", "Consolas", "Courier New", monospace;

  --fs-h1: clamp(2.4rem, 5.2vw, 3.6rem);
  --fs-h2: clamp(1.7rem, 3.2vw, 2.4rem);
  --fs-h3: clamp(1.2rem, 1.8vw, 1.5rem);
  --fs-body: 1rem;
  --fs-small: 0.875rem;
  --fs-caption: 0.75rem;
  --fs-data-lg: clamp(2rem, 4vw, 3rem);

  --space-2xs: 0.25rem;
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1.25rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 5rem;

  --content-width: 1280px;
  --header-height: 76px;
  --nav-width-mobile: 100%;
  --transition-speed: 0.3s;
  --transition-ease: cubic-bezier(0.25, 0.1, 0.25, 1);
  --shadow-panel: 0 8px 30px rgba(0, 0, 0, 0.35);
  --shadow-gold: 0 4px 24px rgba(201, 162, 39, 0.25);
  --clip-corner: polygon(0 0, calc(100% - 16px) 0, 100% 16px, 100% 100%, 16px 100%, 0 calc(100% - 16px));
  --clip-corner-sm: polygon(0 0, calc(100% - 10px) 0, 100% 10px, 100% 100%, 10px 100%, 0 calc(100% - 10px));
}

/* ============ BASE ============ */
html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

html:focus-within {
  scroll-behavior: smooth;
}

@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;
  }
}

body {
  font-family: var(--font-body);
  font-size: var(--fs-body);
  line-height: 1.6;
  color: var(--color-text-light);
  background-color: var(--color-navy);
  background-image:
    linear-gradient(rgba(7, 15, 29, 0.6) 1px, transparent 1px),
    linear-gradient(90deg, rgba(7, 15, 29, 0.6) 1px, transparent 1px);
  background-size: 48px 48px;
  background-position: center top;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body.nav-is-open {
  overflow: hidden;
}

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

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

a:hover {
  color: var(--color-gold-light);
  text-decoration: underline;
  text-underline-offset: 4px;
}

ul,
ol {
  list-style: none;
}

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

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

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

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: -100px;
  left: 20px;
  z-index: 9999;
  padding: 12px 24px;
  background: var(--color-gold);
  color: var(--color-navy);
  font-weight: 700;
  clip-path: var(--clip-corner-sm);
  transition: top 0.25s ease;
  text-decoration: none;
}

.skip-link:focus {
  top: 16px;
  color: var(--color-navy);
  text-decoration: none;
}

/* ============ PAGE SHELL & TYPOGRAPHY ============ */
.page-shell {
  width: 100%;
  max-width: var(--content-width);
  margin-inline: auto;
  padding-inline: var(--space-lg);
}

#main-content {
  outline: none;
  display: block;
}

.page-title-block {
  padding: var(--space-xl) 0 var(--space-lg);
  border-bottom: 2px solid var(--color-navy-border);
  margin-bottom: var(--space-lg);
  position: relative;
}

.page-title-block::after {
  content: "";
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 120px;
  height: 2px;
  background: var(--color-gold);
}

.page-title {
  font-family: var(--font-heading);
  font-size: var(--fs-h1);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: 0.01em;
  color: var(--color-text-light);
  text-transform: uppercase;
}

.page-subtitle {
  font-size: var(--fs-body);
  color: var(--color-text-muted);
  margin-top: var(--space-sm);
  max-width: 640px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  align-items: center;
  padding: var(--space-md) 0;
}

.breadcrumb-link {
  font-size: var(--fs-small);
  color: var(--color-text-muted);
}

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

.breadcrumb-current {
  font-size: var(--fs-small);
  color: var(--color-gold);
  font-weight: 700;
}

.section-block {
  margin-bottom: var(--space-2xl);
}

.section-title {
  font-family: var(--font-heading);
  font-size: var(--fs-h2);
  font-weight: 800;
  line-height: 1.2;
  color: var(--color-text-light);
  margin-bottom: var(--space-md);
  position: relative;
}

.section-title::before {
  content: "//";
  color: var(--color-gold);
  margin-right: 0.5em;
}

.section-score {
  font-family: var(--font-heading);
  font-size: var(--fs-h3);
  font-weight: 700;
  color: var(--color-cream);
}

.body-copy {
  color: var(--color-text-light);
  max-width: 68ch;
  margin-bottom: var(--space-lg);
}

.body-copy p {
  margin-bottom: var(--space-md);
}

/* ============ HEADER ============ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--color-navy-deep);
  border-bottom: 1px solid var(--color-navy-border);
  box-shadow: 0 0 24px rgba(0, 0, 0, 0.2);
}

.site-header-inner {
  display: flex;
  align-items: stretch;
  max-width: var(--content-width);
  margin-inline: auto;
  padding-inline: var(--space-lg);
  min-height: var(--header-height);
  gap: var(--space-lg);
}

.header-progress {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: transparent;
  z-index: 2;
}

.header-progress-bar {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--color-gold), var(--color-gold-light));
  box-shadow: 0 0 12px rgba(201, 162, 39, 0.4);
}

.brand-lockup {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
  padding: var(--space-sm) 0;
  flex-shrink: 0;
}

.brand-lockup:hover {
  text-decoration: none;
}

.brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: var(--color-gold);
  clip-path: var(--clip-corner-sm);
  position: relative;
  flex-shrink: 0;
}

.brand-mark-corner {
  position: absolute;
  width: 8px;
  height: 8px;
  top: 6px;
  right: 6px;
  background: var(--color-navy-deep);
  clip-path: var(--clip-corner-sm);
}

.brand-mark-text {
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.6rem;
  color: var(--color-navy-deep);
  transform: translate(-2px, -2px);
}

.brand-copy {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.brand-name {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.25rem;
  line-height: 1.2;
  color: var(--color-text-light);
  letter-spacing: 0.04em;
}

.brand-sub {
  font-size: var(--fs-caption);
  color: var(--color-gold);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  margin-left: auto;
}

.nav-link {
  position: relative;
  display: flex;
  align-items: center;
  align-self: stretch;
  padding: 0 var(--space-sm);
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color 0.25s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 50%;
  width: 0;
  height: 3px;
  background: var(--color-gold);
  transform: translateX(-50%);
  transition: width 0.25s var(--transition-ease);
}

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

.nav-link:hover::after {
  width: 80%;
}

.nav-link[aria-current="page"] {
  color: var(--color-gold);
  font-weight: 700;
}

.nav-link[aria-current="page"]::after {
  width: 80%;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 48px;
  height: 48px;
  background: transparent;
  border: 1px solid var(--color-navy-border);
  padding: 12px;
  margin-left: auto;
  transition: border-color 0.3s ease;
  align-self: center;
}

.nav-toggle-line {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--color-gold);
  transition: transform 0.3s var(--transition-ease), opacity 0.2s ease;
}

.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);
}

.header-slash {
  height: 4px;
  background: repeating-linear-gradient(90deg, var(--color-gold) 0 12px, transparent 12px 32px);
  opacity: 0.5;
}

/* ============ FOOTER ============ */
.site-footer {
  background: var(--color-navy-deep);
  border-top: 4px solid var(--color-gold-deep);
  margin-top: var(--space-2xl);
  position: relative;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: -4px;
  left: 0;
  right: 40%;
  height: 4px;
  background: var(--color-gold);
}

.footer-top {
  max-width: var(--content-width);
  margin-inline: auto;
  padding: var(--space-xl) var(--space-lg) var(--space-lg);
  display: grid;
  grid-template-columns: minmax(280px, 1.4fr) minmax(200px, 0.6fr);
  gap: var(--space-xl);
}

.footer-brand-area {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: var(--space-md);
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  text-decoration: none;
}

.footer-brand:hover {
  text-decoration: none;
}

.footer-brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: var(--color-gold);
  color: var(--color-navy-deep);
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.4rem;
  clip-path: var(--clip-corner-sm);
}

.footer-brand-copy {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer-brand-name {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--color-text-light);
}

.footer-brand-tagline {
  font-size: var(--fs-caption);
  color: var(--color-text-muted);
  letter-spacing: 0.04em;
}

.footer-trust {
  font-size: var(--fs-small);
  color: var(--color-text-muted);
  max-width: 48ch;
  line-height: 1.7;
}

.footer-touchline {
  font-size: var(--fs-caption);
  color: var(--color-gold-deep);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  writing-mode: horizontal-tb;
  border-left: 2px solid var(--color-gold-deep);
  padding-left: var(--space-sm);
  margin-top: var(--space-sm);
  opacity: 0.7;
}

.footer-link-groups {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}

.footer-link-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer-heading {
  font-family: var(--font-heading);
  font-size: 0.8125rem;
  font-weight: 700;
  color: var(--color-gold);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  margin-bottom: var(--space-sm);
  padding-bottom: var(--space-xs);
  border-bottom: 1px solid var(--color-navy-border);
}

.footer-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.footer-link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  font-size: var(--fs-small);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-link::before {
  content: "→";
  color: var(--color-gold);
  font-family: var(--font-data);
  opacity: 0;
  transform: translateX(-4px);
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.footer-link:hover {
  color: var(--color-text-light);
  text-decoration: none;
}

.footer-link:hover::before {
  opacity: 1;
  transform: translateX(0);
}

.footer-bottom {
  border-top: 1px solid var(--color-navy-border);
  padding: var(--space-md) var(--space-lg);
  max-width: var(--content-width);
  margin-inline: auto;
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.footer-contact {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
  align-items: center;
  font-size: var(--fs-small);
  color: var(--color-text-muted);
}

.footer-contact-line {
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color 0.2s ease;
}

.footer-contact-line:hover {
  color: var(--color-gold);
  text-decoration: none;
}

.footer-contact-divider {
  color: var(--color-gold-deep);
  opacity: 0.7;
}

.footer-contact-address {
  color: var(--color-text-muted);
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-md);
  font-size: var(--fs-caption);
  color: var(--color-text-muted);
  opacity: 0.75;
}

.footer-icp {
  font-family: var(--font-data);
  color: var(--color-gold);
}

/* ============ BACK TO TOP ============ */
.back-top-btn {
  position: fixed;
  right: var(--space-md);
  bottom: var(--space-md);
  z-index: 100;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  width: 56px;
  height: 56px;
  background: var(--color-navy-panel);
  border: 1px solid var(--color-gold);
  clip-path: var(--clip-corner);
  color: var(--color-gold);
  box-shadow: var(--shadow-gold);
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease, background-color 0.2s ease;
}

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

.back-top-btn:hover {
  background: var(--color-gold);
  color: var(--color-navy);
}

.back-top-arrow {
  font-size: 1.5rem;
  line-height: 1;
  font-weight: 700;
}

.back-top-text {
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* ============ COMMON BUTTONS ============ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: 12px 28px;
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 700;
  line-height: 1.2;
  text-decoration: none;
  border: none;
  cursor: pointer;
  transition: background-color 0.25s ease, color 0.25s ease, box-shadow 0.25s ease, transform 0.2s ease;
  transform: skewX(-4deg);
}

.btn > * {
  transform: skewX(4deg);
}

.btn:hover {
  text-decoration: none;
}

.btn:active {
  transform: skewX(-4deg) translateY(2px);
}

.btn-gold {
  background: var(--color-gold);
  color: var(--color-navy-deep);
  box-shadow: 0 4px 16px rgba(201, 162, 39, 0.25);
}

.btn-gold:hover {
  background: var(--color-gold-light);
  color: var(--color-navy-deep);
  box-shadow: 0 6px 20px rgba(201, 162, 39, 0.35);
}

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

.btn-ghost:hover {
  background: rgba(201, 162, 39, 0.12);
  color: var(--color-gold-light);
}

.btn-block {
  display: flex;
  width: 100%;
}

/* ============ PANELS & CARDS ============ */
.panel-cut {
  position: relative;
  background: var(--color-navy-panel);
  border: 1px solid var(--color-navy-border);
  clip-path: var(--clip-corner);
  padding: var(--space-lg);
}

.panel-cut::before {
  content: "";
  position: absolute;
  top: 0;
  right: 24px;
  width: 36px;
  height: 3px;
  background: var(--color-gold);
}

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

.panel-gold::after {
  content: "";
  position: absolute;
  top: -1px;
  right: -1px;
  width: 16px;
  height: 16px;
  background: var(--color-gold);
  clip-path: var(--clip-corner-sm);
}

.panel-dark {
  background: var(--color-navy-deep);
}

.panel-cream {
  background: var(--color-cream);
  color: var(--color-text-dark);
}

.panel-cream h1,
.panel-cream h2,
.panel-cream h3,
.panel-cream h4 {
  color: var(--color-text-dark);
}

/* ============ TAGS, DATA, STATUS ============ */
.tag-chip {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2xs);
  padding: 4px 12px;
  background: var(--color-navy-panel);
  border: 1px solid var(--color-navy-border);
  font-size: var(--fs-caption);
  color: var(--color-cream-dim);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  white-space: nowrap;
}

.tag-chip.is-hot {
  border-color: var(--color-red);
  color: var(--color-cream);
  background: rgba(229, 72, 77, 0.12);
}

.tag-chip.is-gold {
  border-color: var(--color-gold);
  color: var(--color-gold);
}

.score-number {
  font-family: var(--font-data);
  font-weight: 700;
  font-size: var(--fs-data-lg);
  line-height: 1;
  color: var(--color-gold);
  letter-spacing: -0.04em;
  font-variant-numeric: tabular-nums;
}

.data-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  border-bottom: 1px solid rgba(44, 62, 80, 0.7);
  font-size: var(--fs-small);
}

.data-row:last-child {
  border-bottom: none;
}

.data-row-label {
  color: var(--color-text-muted);
}

.data-row-value {
  font-family: var(--font-data);
  font-weight: 700;
  color: var(--color-text-light);
  font-variant-numeric: tabular-nums;
}

.data-trend-up {
  color: var(--color-green);
}

.data-trend-down {
  color: var(--color-chart-red);
}

.status-dot {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: var(--fs-caption);
  color: var(--color-text-muted);
}

.status-dot::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 2px;
  background: var(--color-green);
  flex-shrink: 0;
  animation: pulse-dot 2s infinite;
}

.status-dot.is-warning::before {
  background: var(--color-red);
}

@keyframes pulse-dot {
  0%,
  100% {
    opacity: 1;
    box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.5);
  }
  50% {
    opacity: 0.75;
    box-shadow: 0 0 0 5px rgba(16, 185, 129, 0);
  }
}

/* ============ VERTICAL CAPTIONS, DIVIDERS ============ */
.vertical-caption {
  writing-mode: vertical-rl;
  text-orientation: mixed;
  font-size: var(--fs-caption);
  color: var(--color-text-muted);
  letter-spacing: 0.18em;
  text-transform: uppercase;
  border-left: 1px solid var(--color-gold-deep);
  padding-left: var(--space-xs);
  padding-top: var(--space-sm);
}

.divider-slash {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  color: var(--color-gold);
  font-family: var(--font-data);
  font-size: var(--fs-caption);
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.divider-slash::before {
  content: "";
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--color-gold), transparent);
}

.divider-slash::after {
  content: "///";
  color: var(--color-gold);
  font-weight: 700;
}

.divider-slash.is-center::after {
  content: "";
}

/* ============ IMAGE FRAME ============ */
.image-frame {
  position: relative;
  background: var(--color-navy-panel);
  border: 1px solid var(--color-navy-border);
  clip-path: var(--clip-corner);
  overflow: hidden;
  aspect-ratio: 16/9;
}

.image-frame::before {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    45deg,
    transparent 0 12px,
    rgba(201, 162, 39, 0.04) 12px 16px
  );
  pointer-events: none;
  z-index: 1;
}

.image-frame::after {
  content: "IMG";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--font-data);
  font-size: 0.8125rem;
  color: var(--color-gold-deep);
  letter-spacing: 0.24em;
  z-index: 0;
}

.image-frame img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 2;
}

.image-frame.is-digit-ratio {
  aspect-ratio: 3/4;
}

.image-frame.is-wide-ratio {
  aspect-ratio: 2.2/1;
}

.image-frame.is-square-ratio {
  aspect-ratio: 1/1;
}

/* ============ RESPONSIVE ============ */
@media (max-width: 1024px) {
  .footer-top {
    grid-template-columns: 1fr;
    gap: var(--space-lg);
  }
}

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

  .site-header-inner {
    flex-wrap: wrap;
    align-items: center;
    padding-inline: var(--space-md);
    gap: var(--space-sm);
  }

  .brand-lockup {
    padding: var(--space-xs) 0;
    flex: 1;
  }

  .brand-mark {
    width: 42px;
    height: 42px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    display: flex;
    flex-direction: column;
    width: var(--nav-width-mobile);
    background: var(--color-navy-deep);
    border-top: 1px solid var(--color-navy-border);
    border-bottom: 1px solid var(--color-navy-border);
    padding: var(--space-xs) var(--space-md) var(--space-md);
    gap: 0;
    margin-left: auto;
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    transform: translateY(-120%);
    visibility: hidden;
    opacity: 0;
    transition: transform 0.3s var(--transition-ease), opacity 0.3s ease, visibility 0s linear 0.3s;
    z-index: 99;
    pointer-events: none;
  }

  .site-nav[data-open="true"] {
    transform: translateY(0);
    visibility: visible;
    opacity: 1;
    transition: transform 0.3s var(--transition-ease), opacity 0.25s ease;
    pointer-events: auto;
  }

  .nav-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-sm);
    border-bottom: 1px solid var(--color-navy-border);
    width: 100%;
    min-height: 48px;
    font-size: 0.9375rem;
  }

  .nav-link:last-child {
    border-bottom: none;
  }

  .nav-link::after {
    display: none;
  }

  .nav-link[aria-current="page"] {
    border-left: 3px solid var(--color-gold);
    padding-left: calc(var(--space-sm) + 3px);
  }

  .footer-bottom {
    padding: var(--space-sm) var(--space-md);
    gap: var(--space-xs);
  }

  .footer-contact {
    gap: var(--space-xs);
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-contact-divider {
    display: none;
  }

  .page-shell {
    padding-inline: var(--space-md);
  }

  .back-top-btn {
    right: var(--space-sm);
    bottom: var(--space-sm);
    width: 48px;
    height: 48px;
  }

  .back-top-text {
    font-size: 0.5rem;
  }
}

@media (max-width: 520px) {
  .brand-sub {
    display: none;
  }

  .brand-name {
    font-size: 1.05rem;
  }

  .footer-link-groups {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }
}

@media (prefers-reduced-motion: reduce) {
  .status-dot::before {
    animation: none;
  }

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

/* 大屏增强 */
@media (min-width: 1600px) {
  :root {
    --content-width: 1440px;
  }
}

/* 允许浏览器默认滚动条样式 + 自定义 */
::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: var(--color-navy-deep);
}

::-webkit-scrollbar-thumb {
  background: var(--color-navy-border);
  border-radius: 0;
  border: none;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-gold-deep);
}