:root {
  --deep-blue: #0B1B3A;
  --secondary-blue: #14264B;
  --orange: #F77F00;
  --green: #2A9D8F;
  --cream: #F8F7F5;
  --ink: #1A1A1A;
  --fog: #6C8EBF;
  --yellow: #FCBF49;
  --white: #FFFFFF;
  --font-display: "Archivo", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-body: "Inter", "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  --container: 1180px;
  --gutter: clamp(18px, 4vw, 48px);
  --radius-s: 6px;
  --radius-m: 12px;
  --radius-l: 20px;
  --shadow-soft: 0 18px 40px rgba(11, 27, 58, 0.12);
  --shadow-card: 0 8px 24px rgba(11, 27, 58, 0.08);
}

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

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

body,
h1,
h2,
h3,
h4,
p,
ul,
ol,
figure,
blockquote {
  margin: 0;
}

body {
  min-height: 100vh;
  background: var(--cream);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.7;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}

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

ul,
ol {
  padding: 0;
}

button {
  font: inherit;
  border: 0;
}

a {
  color: var(--deep-blue);
}

a:focus-visible,
button:focus-visible,
[tabindex]:focus-visible {
  outline: 2px solid var(--orange);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: var(--orange);
  color: var(--deep-blue);
}

:target {
  scroll-margin-top: 96px;
}

.container {
  width: min(var(--container), calc(100% - 2 * var(--gutter)));
  margin-inline: auto;
}

.container--narrow {
  max-width: 860px;
}

.section {
  padding: clamp(48px, 8vw, 88px) 0;
}

.section--tight {
  padding: clamp(32px, 5vw, 56px) 0;
}

.section--dark {
  background: var(--deep-blue);
  color: var(--cream);
}

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

.section-head {
  max-width: 780px;
  margin-bottom: 36px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 12px;
  letter-spacing: 0.24em;
  text-transform: uppercase;
  color: var(--orange);
}

.eyebrow::before {
  content: "";
  width: 24px;
  height: 2px;
  background: var(--green);
}

.eyebrow--light {
  color: var(--yellow);
}

.display-title {
  color: var(--deep-blue);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(42px, 8vw, 76px);
  line-height: 0.98;
  letter-spacing: -0.04em;
  text-transform: uppercase;
}

.lead {
  color: var(--secondary-blue);
  font-size: clamp(17px, 2vw, 20px);
  line-height: 1.6;
}

.skip-link {
  position: fixed;
  top: -96px;
  left: 16px;
  z-index: 300;
  background: var(--orange);
  color: var(--deep-blue);
  padding: 10px 16px;
  font-weight: 800;
  border-radius: 0 0 10px 10px;
  text-decoration: none;
  box-shadow: var(--shadow-soft);
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 0;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--deep-blue);
  color: var(--cream);
}

.site-header::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 3px;
  background: repeating-linear-gradient(
    90deg,
    var(--orange) 0 8px,
    transparent 8px 16px,
    var(--green) 16px 24px,
    transparent 24px 32px
  );
  opacity: 0.55;
  pointer-events: none;
}

.header-upper {
  background: var(--deep-blue);
  border-bottom: 1px solid rgba(248, 247, 245, 0.14);
}

.header-upper-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 14px 0;
}

.brand-lockup {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--cream);
}

.brand-lockup__text {
  display: grid;
  gap: 2px;
  line-height: 1.2;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 10px 2px 10px 2px;
  background: var(--orange);
  color: var(--deep-blue);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  letter-spacing: 0.02em;
  box-shadow: 4px 4px 0 rgba(247, 127, 0, 0.25);
}

.brand-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 22px;
  letter-spacing: 0.06em;
}

.brand-slogan {
  font-size: 12px;
  color: var(--fog);
  letter-spacing: 0.1em;
}

.hb-system {
  text-align: right;
}

.hb-system__prefix {
  display: block;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 12px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--yellow);
}

.hb-system__tag {
  display: block;
  font-size: 12px;
  color: var(--fog);
  margin-top: 4px;
  letter-spacing: 0.04em;
}

.header-nav {
  position: relative;
  background: var(--secondary-blue);
  border-bottom: 2px solid var(--orange);
}

.header-nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 58px;
}

.site-nav {
  display: flex;
  align-items: center;
  flex: 1;
  min-width: 0;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
  list-style: none;
}

.nav-item {
  position: relative;
}

.nav-link {
  position: relative;
  display: block;
  padding: 10px 14px;
  border-radius: var(--radius-s);
  color: var(--cream);
  font-weight: 600;
  font-size: 15px;
  text-decoration: none;
  transition: background 0.2s ease, color 0.2s ease;
}

.nav-link:hover {
  color: var(--white);
  background: rgba(248, 247, 245, 0.08);
}

.nav-link[aria-current="page"] {
  color: var(--orange);
  background: rgba(247, 127, 0, 0.12);
}

.nav-link[aria-current="page"]::after {
  content: "";
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 0;
  height: 2px;
  background: var(--orange);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--orange);
  color: var(--deep-blue);
  font-weight: 800;
  font-size: 14px;
  white-space: nowrap;
  padding: 10px 16px;
  border-radius: 8px;
  text-decoration: none;
  box-shadow: 0 4px 0 rgba(0, 0, 0, 0.2);
  transition: background 0.2s ease, transform 0.2s ease;
}

.nav-cta:hover {
  background: var(--yellow);
  transform: translateY(-1px);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 42px;
  height: 42px;
  padding: 10px;
  background: transparent;
  border: 1px solid rgba(248, 247, 245, 0.3);
  border-radius: 8px;
  cursor: pointer;
}

.nav-toggle__bar {
  display: block;
  height: 2px;
  width: 100%;
  background: var(--cream);
  border-radius: 99px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

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

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

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

.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  z-index: 400;
  background: rgba(248, 247, 245, 0.12);
  pointer-events: none;
}

.reading-progress span {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--orange), var(--yellow) 60%, var(--green));
  transition: width 0.1s linear;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  border-radius: 10px;
  font-weight: 800;
  font-size: 15px;
  text-decoration: none;
  border: 1px solid transparent;
  transition: background 0.2s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

.button--primary {
  background: var(--orange);
  color: var(--deep-blue);
  box-shadow: 0 5px 0 rgba(0, 0, 0, 0.22);
}

.button--primary:hover {
  background: var(--yellow);
  transform: translateY(-1px);
  box-shadow: 0 7px 0 rgba(0, 0, 0, 0.18);
}

.button--ghost {
  background: transparent;
  border-color: var(--deep-blue);
  color: var(--deep-blue);
}

.button--ghost:hover {
  background: rgba(11, 27, 58, 0.06);
}

.button--inverse {
  border-color: rgba(248, 247, 245, 0.24);
}

.site-footer {
  position: relative;
  margin-top: 80px;
  background: var(--deep-blue);
  color: var(--cream);
}

.site-footer::before {
  content: "";
  display: block;
  height: 6px;
  background: linear-gradient(90deg, var(--orange) 0 36%, var(--green) 36% 52%, var(--yellow) 52% 100%);
}

.footer-cta-row {
  background: var(--secondary-blue);
  border-bottom: 1px solid rgba(248, 247, 245, 0.12);
}

.footer-cta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 28px 0;
}

.trust-statement {
  max-width: 728px;
  color: var(--fog);
  font-size: 15px;
  line-height: 1.75;
}

.footer-main {
  padding: 48px 0 36px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr 0.8fr 1.1fr;
  gap: 40px;
}

.footer-brand__logo {
  display: inline-block;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 30px;
  letter-spacing: 0.08em;
  color: var(--cream);
  text-decoration: none;
}

.footer-brand__logo:hover {
  color: var(--yellow);
}

.footer-tagline {
  margin-top: 12px;
  color: var(--fog);
  font-size: 14px;
  line-height: 1.7;
}

.footer-heading {
  color: var(--yellow);
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.footer-list {
  list-style: none;
  display: grid;
  gap: 10px;
}

.footer-link {
  color: var(--cream);
  opacity: 0.82;
  font-size: 14px;
  text-decoration: none;
  transition: opacity 0.2s ease, color 0.2s ease;
}

.footer-link:hover {
  opacity: 1;
  color: var(--orange);
}

.footer-contact p {
  color: var(--fog);
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 8px;
}

.footer-bottom {
  background: rgba(5, 12, 24, 0.4);
  border-top: 1px solid rgba(248, 247, 245, 0.12);
  padding: 16px 0;
}

.footer-bottom-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px 24px;
}

.footer-legal {
  color: rgba(248, 247, 245, 0.68);
  font-size: 13px;
}

.back-top {
  position: fixed;
  right: 18px;
  bottom: 18px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: 1px solid rgba(248, 247, 245, 0.35);
  background: var(--orange);
  color: var(--deep-blue);
  font-size: 22px;
  line-height: 1;
  cursor: pointer;
  box-shadow: var(--shadow-soft);
  z-index: 150;
  transition: transform 0.2s ease, opacity 0.2s ease, background 0.2s ease;
}

.back-top[hidden] {
  display: none !important;
}

.back-top:hover {
  background: var(--yellow);
  transform: translateY(-3px);
}

.content-grid {
  display: grid;
  grid-template-columns: minmax(0, 220px) minmax(0, 1fr);
  gap: clamp(24px, 5vw, 64px);
  align-items: start;
}

.content-grid__sidebar {
  position: sticky;
  top: 96px;
  border-left: 3px solid var(--orange);
  padding-left: 16px;
  font-size: 14px;
  color: var(--secondary-blue);
}

.content-grid__main {
  min-width: 0;
}

.editorial-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.75fr) minmax(0, 1.25fr);
  gap: clamp(24px, 5vw, 72px);
  align-items: start;
}

.editorial-grid__note {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--secondary-blue);
  border-left: 3px solid var(--orange);
  padding-left: 14px;
}

.content-chapter {
  display: grid;
  grid-template-columns: minmax(0, 220px) minmax(0, 1fr);
  gap: clamp(24px, 4vw, 56px);
  align-items: start;
  margin-bottom: clamp(40px, 6vw, 72px);
}

.content-chapter__aside {
  position: sticky;
  top: 96px;
  border-top: 2px solid var(--orange);
  padding-top: 14px;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--secondary-blue);
}

.content-chapter__body {
  min-width: 0;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.card {
  position: relative;
  overflow: hidden;
  background: var(--white);
  border: 1px solid rgba(11, 27, 58, 0.05);
  border-radius: var(--radius-m);
  box-shadow: var(--shadow-card);
  padding: 24px;
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 68px;
  height: 4px;
  background: linear-gradient(90deg, var(--orange), var(--yellow));
}

.card--dark {
  background: var(--secondary-blue);
  color: var(--cream);
}

.stat-card {
  background: var(--white);
  border: 1px solid rgba(11, 27, 58, 0.06);
  border-radius: var(--radius-m);
  box-shadow: var(--shadow-card);
  padding: 22px;
}

.stat-card__value {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(32px, 5vw, 52px);
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--deep-blue);
}

.stat-card__label {
  margin-top: 8px;
  color: var(--secondary-blue);
  font-weight: 600;
  font-size: 14px;
}

.stat-card__bar {
  height: 6px;
  margin-top: 14px;
  background: #E6EAF1;
  border-radius: 99px;
  overflow: hidden;
}

.data-bar {
  display: block;
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--orange), var(--green));
  border-radius: inherit;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  list-style: none;
}

.tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(11, 27, 58, 0.06);
  border: 1px solid rgba(11, 27, 58, 0.08);
  color: var(--deep-blue);
  font-size: 13px;
  font-weight: 600;
}

.tag--orange {
  background: rgba(247, 127, 0, 0.12);
  border-color: rgba(247, 127, 0, 0.3);
  color: var(--deep-blue);
}

.live-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 0 rgba(42, 157, 143, 0.45);
  animation: live-pulse 1.6s infinite;
}

.live-dot--orange {
  background: var(--orange);
  box-shadow: 0 0 0 0 rgba(247, 127, 0, 0.45);
}

@keyframes live-pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(42, 157, 143, 0.45);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(42, 157, 143, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(42, 157, 143, 0);
  }
}

.speed-lines {
  position: relative;
  height: 2px;
  overflow: hidden;
}

.speed-lines::after {
  content: "";
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    90deg,
    var(--orange) 0 8px,
    transparent 8px 18px,
    var(--green) 18px 26px,
    transparent 26px 36px
  );
  animation: shift-line 1.3s linear infinite;
}

@keyframes shift-line {
  from {
    transform: translateX(0);
  }
  to {
    transform: translateX(36px);
  }
}

.media-frame {
  position: relative;
  overflow: hidden;
  background: var(--secondary-blue);
  border-radius: var(--radius-m);
  box-shadow: var(--shadow-soft);
}

.media-frame img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.media-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(11, 27, 58, 0.24) 0%, transparent 42%);
  pointer-events: none;
}

.media-frame--ratio-16-9 {
  aspect-ratio: 16 / 9;
}

.media-frame--ratio-4-3 {
  aspect-ratio: 4 / 3;
}

.media-frame--ratio-21-9 {
  aspect-ratio: 21 / 9;
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  list-style: none;
  padding: 18px 0 22px;
  color: var(--fog);
  font-size: 14px;
}

.breadcrumbs li {
  display: flex;
  align-items: center;
  gap: 6px;
}

.breadcrumbs li + li::before {
  content: "/";
  color: var(--fog);
  opacity: 0.7;
}

.breadcrumbs a {
  color: var(--deep-blue);
  text-decoration: none;
}

.breadcrumbs a:hover {
  color: var(--orange);
}

.toc-panel {
  background: var(--white);
  border: 1px solid rgba(11, 27, 58, 0.08);
  border-left: 3px solid var(--orange);
  border-radius: var(--radius-m);
  box-shadow: var(--shadow-card);
  padding: 20px 22px;
}

.toc-panel--sticky {
  position: sticky;
  top: 96px;
}

.toc-panel__title {
  color: var(--secondary-blue);
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 12px;
}

.toc-list {
  list-style: none;
  display: grid;
  gap: 4px;
}

.toc-link {
  display: block;
  padding: 8px 10px;
  border-radius: var(--radius-s);
  color: var(--secondary-blue);
  font-weight: 600;
  font-size: 14px;
  text-decoration: none;
}

.toc-link:hover {
  background: rgba(247, 127, 0, 0.08);
  color: var(--deep-blue);
}

.toc-link[aria-current="true"] {
  background: var(--deep-blue);
  color: var(--cream);
}

.prose {
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.85;
}

.prose p {
  margin-bottom: 1em;
}

.prose h2,
.prose h3 {
  margin-top: 1.6em;
  margin-bottom: 0.6em;
}

@media (max-width: 920px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

@media (max-width: 860px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    display: none;
    position: absolute;
    left: var(--gutter);
    right: var(--gutter);
    top: 100%;
    z-index: 110;
    background: var(--secondary-blue);
    border-radius: 0 0 14px 14px;
    border-top: 2px solid var(--orange);
    padding: 12px;
    box-shadow: var(--shadow-soft);
  }

  .site-nav[data-open] {
    display: block;
    animation: menu-drop 0.2s ease;
  }

  .nav-list {
    flex-direction: column;
    gap: 0;
  }

  .nav-item + .nav-item {
    border-top: 1px solid rgba(248, 247, 245, 0.08);
  }

  .nav-link {
    padding: 12px 10px;
  }

  .content-grid,
  .editorial-grid,
  .content-chapter {
    grid-template-columns: 1fr;
  }

  .content-grid__sidebar,
  .content-chapter__aside {
    position: static;
  }
}

@keyframes menu-drop {
  from {
    opacity: 0;
    transform: translateY(-6px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 680px) {
  .nav-cta {
    display: none;
  }

  .hb-system__tag {
    display: none;
  }

  .footer-cta-inner {
    flex-direction: column;
    align-items: flex-start;
    padding: 24px 0;
  }
}

@media (max-width: 560px) {
  .footer-grid {
    grid-template-columns: 1fr;
    gap: 28px;
  }

  .hb-system {
    display: none;
  }

  .brand-slogan {
    display: none;
  }

  .brand-mark {
    width: 40px;
    height: 40px;
    font-size: 16px;
  }

  .brand-name {
    font-size: 20px;
  }
}

body.nav-lock {
  overflow: hidden;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}