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

:root {
  --color-bg: #0A1428;
  --color-bg-2: #101F3C;
  --color-bg-3: #1B2F52;
  --color-line: #2A4073;
  --color-text: #E8EEF8;
  --color-text-2: #C5D3E8;
  --color-accent: #FF6B2C;
  --color-accent-2: #FFA270;
  --color-white: #FFFFFF;
  --font-heading: Impact, Haettenschweiler, 'Arial Narrow Bold', 'Noto Sans SC', sans-serif;
  --font-body: 'Helvetica Neue', Arial, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --size-display: clamp(2.5rem, 8vw, 5rem);
  --size-h1: 2.5rem;
  --size-h2: 2rem;
  --size-h3: 1.5rem;
  --size-body: 1rem;
  --size-small: 0.875rem;
  --shadow-1: 0 4px 20px rgba(0, 0, 0, 0.35);
  --shadow-2: 0 14px 30px rgba(0, 0, 0, 0.35);
}

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

body {
  background:
    radial-gradient(1100px 380px at 88% -60px, rgba(27, 47, 82, 0.6), transparent 60%),
    var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: var(--size-body);
  line-height: 1.65;
  padding-top: 86px;
  -webkit-font-smoothing: antialiased;
}

main {
  display: block;
}

main#main-content {
  scroll-margin-top: 110px;
}

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

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

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
}

h1,
h2,
h3 {
  font-family: var(--font-heading);
  font-style: italic;
  font-weight: 900;
  line-height: 1.08;
}

h1 {
  font-size: var(--size-display);
}

h2 {
  font-size: var(--size-h2);
}

h3 {
  font-size: var(--size-h3);
}

::selection {
  background: var(--color-accent);
  color: var(--color-bg);
}

:focus {
  outline: none;
}

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: 4px;
}

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

.skip-link {
  position: fixed;
  top: -100px;
  left: 16px;
  z-index: 3000;
  background: var(--color-accent);
  color: var(--color-bg);
  font-weight: 700;
  font-size: 0.88rem;
  padding: 10px 18px;
  border-radius: 999px;
  box-shadow: var(--shadow-1);
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 16px;
}

/* ===== 悬浮胶囊导航 ===== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: 14px 20px 0;
  pointer-events: none;
  transition: padding 0.3s ease;
}

.site-header.is-scrolled {
  padding-top: 8px;
}

.site-header__inner {
  pointer-events: auto;
  position: relative;
  max-width: 1320px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 8px 8px 14px;
  background: rgba(9, 16, 36, 0.82);
  border: 1px solid var(--color-line);
  border-radius: 999px;
  box-shadow: var(--shadow-1);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.site-header.is-scrolled .site-header__inner {
  background: rgba(8, 14, 30, 0.92);
  box-shadow: 0 8px 28px rgba(0, 0, 0, 0.45);
}

.site-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: none;
}

.site-brand__mark {
  position: relative;
  width: 38px;
  height: 38px;
  flex: none;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-accent);
  transform: skewX(-10deg);
  box-shadow: -4px 4px 0 rgba(255, 107, 44, 0.35);
}

.site-brand__core {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 900;
  font-style: italic;
  line-height: 1;
  color: var(--color-bg);
  transform: skewX(10deg);
}

.site-brand__slash {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.site-brand__slash::before,
.site-brand__slash::after {
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  width: 2px;
  background: rgba(10, 20, 40, 0.28);
  transform: skewX(10deg);
}

.site-brand__slash::before {
  left: 8px;
}

.site-brand__slash::after {
  right: 8px;
}

.site-brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.1;
}

.site-brand__name {
  font-family: var(--font-heading);
  font-size: 1.25rem;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--color-text);
}

.site-brand__slogan {
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-text-2);
}

.site-nav {
  margin-inline: auto;
}

.site-nav__list {
  display: flex;
  align-items: center;
  gap: 2px;
}

.site-nav__link {
  display: block;
  padding: 8px 13px;
  border-radius: 999px;
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--color-text-2);
  white-space: nowrap;
  transition: color 0.2s ease, background 0.2s ease;
}

.site-nav__link:hover {
  color: var(--color-text);
  background: rgba(42, 64, 115, 0.4);
}

.site-nav__link[aria-current="page"] {
  color: var(--color-accent);
  background: rgba(255, 107, 44, 0.14);
}

.site-header__cta {
  flex: none;
}

.site-nav__toggle {
  display: none;
  flex: none;
  width: 40px;
  height: 40px;
  border: 1px solid var(--color-line);
  background: var(--color-bg-2);
  border-radius: 50%;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
  padding: 10px 9px;
}

.site-nav__toggle-line {
  display: block;
  width: 20px;
  height: 2px;
  background: var(--color-text);
  transition: transform 0.25s ease, opacity 0.25s ease;
}

.site-header[data-open="true"] .site-nav__toggle-line:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.site-header[data-open="true"] .site-nav__toggle-line:nth-child(2) {
  opacity: 0;
}

.site-header[data-open="true"] .site-nav__toggle-line:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ===== 顶部阅读进度 ===== */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  z-index: 1100;
  background: rgba(42, 64, 115, 0.3);
  pointer-events: none;
}

.reading-progress__bar {
  display: block;
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--color-accent), var(--color-accent-2));
  transition: width 0.1s linear;
}

/* ===== 页脚 ===== */
.site-footer {
  position: relative;
  margin-top: 80px;
  background:
    linear-gradient(180deg, rgba(255, 107, 44, 0.06), rgba(255, 107, 44, 0) 220px),
    var(--color-bg-2);
  border-top: 1px solid var(--color-line);
}

.site-footer::before {
  content: '';
  position: absolute;
  top: -1px;
  left: 0;
  width: 140px;
  height: 3px;
  background: var(--color-accent);
}

.site-footer__main {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.4fr;
  gap: 48px 40px;
  padding-block: 64px 48px;
}

.site-footer__brand {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-style: italic;
  font-weight: 900;
  color: var(--color-text);
}

.site-footer__tagline {
  margin-top: 4px;
  font-size: 0.85rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.site-footer__trust {
  margin-top: 16px;
  max-width: 38ch;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--color-text-2);
  border-left: 2px solid var(--color-accent);
  padding-left: 14px;
}

.site-footer__title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 900;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-line);
}

.site-footer__item {
  font-size: 0.9rem;
  line-height: 1.5;
  color: var(--color-text-2);
}

.site-footer__item + .site-footer__item {
  margin-top: 6px;
}

.site-footer__link {
  position: relative;
  display: inline-block;
  padding: 4px 0 4px 16px;
  color: var(--color-text-2);
  transition: color 0.2s ease;
}

.site-footer__link::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  width: 6px;
  height: 6px;
  background: var(--color-line);
  transform: translateY(-50%) skewX(-12deg);
  transition: background 0.2s ease, width 0.2s ease;
}

.site-footer__link:hover {
  color: var(--color-text);
}

.site-footer__link:hover::before {
  background: var(--color-accent);
  width: 10px;
}

.site-footer__bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 24px;
  padding-block: 20px 24px;
  border-top: 1px solid var(--color-line);
  font-size: 0.82rem;
  color: var(--color-text-2);
}

.site-footer__bottom p {
  margin: 0;
}

.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.site-footer__legal a {
  color: var(--color-text-2);
  transition: color 0.2s ease;
}

.site-footer__legal a:hover {
  color: var(--color-accent);
}

/* ===== 通用容器与区块 ===== */
.container {
  width: 100%;
  max-width: 1440px;
  margin-inline: auto;
  padding-inline: 20px;
}

.section {
  padding-block: 72px;
}

.section--tight {
  padding-block: 40px;
}

.section__head {
  max-width: 880px;
  margin-bottom: 40px;
}

.section__kicker {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-accent);
  border: 1px solid rgba(255, 107, 44, 0.4);
  border-radius: 2px;
  padding: 4px 10px;
  margin-bottom: 14px;
}

.section__title {
  font-size: var(--size-h2);
  color: var(--color-text);
}

.section__lead {
  margin-top: 12px;
  max-width: 62ch;
  color: var(--color-text-2);
}

/* ===== 网格 ===== */
.grid {
  display: grid;
  gap: 20px;
}

.grid--split-1-2 {
  grid-template-columns: 1fr 2fr;
}

.grid--split-2-1 {
  grid-template-columns: 2fr 1fr;
}

.grid--split-3-1 {
  grid-template-columns: 3fr 1fr;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  padding: 10px 20px;
  border: 1px solid transparent;
  border-radius: 999px;
  text-decoration: none;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

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

.btn--primary:hover {
  background: var(--color-accent-2);
  transform: translateY(-1px);
}

.btn--ghost {
  background: transparent;
  border-color: var(--color-line);
  color: var(--color-text);
}

.btn--ghost:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ===== 资料卡 ===== */
.card {
  position: relative;
  background: var(--color-bg-2);
  border: 1px solid var(--color-line);
  padding: 24px;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 36px;
  height: 3px;
  background: var(--color-accent);
  opacity: 0.9;
}

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

.card__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
}

.card__title {
  font-size: 1.15rem;
  color: var(--color-text);
}

.card__body {
  font-size: 0.92rem;
  color: var(--color-text-2);
}

.card__foot {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--color-line);
}

/* ===== 标签、面包屑、动势条 ===== */
.tag {
  display: inline-block;
  padding: 3px 10px;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-text-2);
  border: 1px solid var(--color-line);
  border-radius: 2px;
}

.tag--accent {
  color: var(--color-accent);
  border-color: rgba(255, 107, 44, 0.5);
  background: rgba(255, 107, 44, 0.08);
}

.breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 0.82rem;
  color: var(--color-text-2);
  padding: 14px 0;
  border-bottom: 1px solid var(--color-line);
  margin-bottom: 32px;
}

.breadcrumbs a {
  color: var(--color-text-2);
  transition: color 0.2s ease;
}

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

.breadcrumbs__sep {
  color: var(--color-line);
}

.data-strip {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-heading);
  font-style: italic;
  font-size: 0.85rem;
  letter-spacing: 0.08em;
  color: var(--color-accent);
  user-select: none;
}

.data-strip::before,
.data-strip::after {
  content: '';
  height: 2px;
  flex: 1;
  transform: skewX(-30deg);
  background: repeating-linear-gradient(90deg, var(--color-line) 0 6px, transparent 6px 10px);
}

.data-strip b {
  font-weight: 900;
}

/* ===== 图片容器 ===== */
.img-shell {
  position: relative;
  overflow: hidden;
  aspect-ratio: 16 / 9;
  background: var(--color-bg-3);
  border: 1px solid var(--color-line);
}

.img-shell--tall {
  aspect-ratio: 4 / 5;
}

.img-shell--wide {
  aspect-ratio: 21 / 9;
}

.img-shell::after {
  content: attr(data-label);
  position: absolute;
  inset: auto 0 0 0;
  padding: 6px 10px;
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  text-align: right;
  color: var(--color-text-2);
  background: linear-gradient(0deg, rgba(10, 20, 40, 0.8), transparent);
}

/* ===== 章节指示器 ===== */
.chapter-indicator {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-heading);
  font-style: italic;
  font-size: 0.95rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--color-text-2);
  background: var(--color-bg-2);
  border: 1px solid var(--color-line);
  border-left: 3px solid var(--color-accent);
  padding: 6px 14px;
}

.chapter-indicator [data-chapter-num] {
  color: var(--color-accent);
}

.chapter-indicator [data-chapter-label-out] {
  color: var(--color-text);
}

/* ===== 滚动显现与章节高亮 ===== */
[data-reveal] {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

[data-reveal][data-revealed="true"] {
  opacity: 1;
  transform: none;
}

[data-chapter] {
  border-left: 2px solid transparent;
  transition: border-color 0.3s ease;
}

[data-chapter][data-active="true"] {
  border-left-color: var(--color-accent);
}

/* ===== 响应式 ===== */
@media (max-width: 960px) {
  .site-header__inner {
    flex-wrap: wrap;
    border-radius: 22px;
    padding: 8px;
  }

  .site-nav {
    order: 4;
    width: 100%;
    margin: 8px 0 2px;
    display: none;
  }

  .site-header[data-open="true"] .site-nav {
    display: block;
  }

  .site-nav__list {
    flex-direction: column;
    align-items: stretch;
  }

  .site-nav__link {
    padding: 12px 14px;
    font-size: 1rem;
    text-align: center;
    border-radius: 12px;
  }

  .site-nav__toggle {
    display: inline-flex;
    margin-left: auto;
  }

  .site-header__cta {
    display: none;
  }

  .site-brand__slogan {
    display: none;
  }

  .site-footer__main {
    grid-template-columns: 1fr 1fr;
  }

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

@media (max-width: 600px) {
  .site-footer__main {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .site-footer__bottom {
    flex-direction: column;
    align-items: flex-start;
  }

  .section {
    padding-block: 48px;
  }
}

/* ===== 减少动效 ===== */
@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;
  }

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