:root {
  --ice: #ebf4f6;
  --mist: #d1e8ed;
  --orange: #ff5a36;
  --orange-dark: #d83f20;
  --night: #1e293b;
  --ink: #182331;
  --muted: #64748b;
  --line: rgba(30, 41, 59, 0.14);
  --surface: rgba(255, 255, 255, 0.82);
  --surface-solid: #ffffff;
  --shadow: 0 18px 48px rgba(30, 41, 59, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  line-height: 1.72;
  background:
    radial-gradient(circle at 12% 8%, rgba(255, 90, 54, 0.18), transparent 28rem),
    linear-gradient(135deg, var(--ice), var(--mist));
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(30, 41, 59, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(30, 41, 59, 0.035) 1px, transparent 1px);
  background-size: 34px 34px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.72), transparent 72%);
}

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

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

a,
button,
.btn,
.card,
.metric,
.mini-card,
.content-block,
.faq-item,
.guide-step,
.code-row,
.preview-shot,
.gallery img,
.media-grid img,
.page-hero img {
  transition:
    transform 0.24s ease,
    border-color 0.24s ease,
    box-shadow 0.24s ease,
    background 0.24s ease,
    color 0.24s ease,
    opacity 0.24s ease;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid rgba(255, 255, 255, 0.2);
  background: rgba(30, 41, 59, 0.94);
  color: #fff;
  backdrop-filter: blur(14px);
}

.nav {
  width: min(1180px, calc(100% - 32px));
  min-height: 72px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 180px;
}

.brand img {
  width: 42px;
  height: 42px;
  object-fit: contain;
}

.brand strong {
  display: block;
  font-size: 18px;
  line-height: 1.1;
}

.brand span {
  display: block;
  margin-top: 3px;
  color: rgba(255, 255, 255, 0.66);
  font-size: 12px;
  line-height: 1.2;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 6px;
}

.nav-links a {
  position: relative;
  padding: 8px 10px;
  border-radius: 6px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 14px;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 10px;
  right: 10px;
  bottom: 4px;
  height: 2px;
  border-radius: 999px;
  background: var(--orange);
  opacity: 0;
  transform: scaleX(0.55);
  transition: opacity 0.24s ease, transform 0.24s ease;
}

.nav-links a:hover,
.nav-links a.active {
  background: rgba(255, 90, 54, 0.18);
  color: #fff;
}

.nav-links a:hover::after,
.nav-links a.active::after {
  opacity: 1;
  transform: scaleX(1);
}

.hero {
  position: relative;
  overflow: hidden;
  min-height: calc(100vh - 72px);
  display: grid;
  align-items: center;
  padding: 52px 0 44px;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, rgba(235, 244, 246, 0.96) 0%, rgba(235, 244, 246, 0.88) 38%, rgba(209, 232, 237, 0.24) 67%, rgba(30, 41, 59, 0.1) 100%),
    url("../img/cover.webp") center right / cover no-repeat;
}

.hero-inner {
  position: relative;
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(320px, 0.75fr);
  gap: 44px;
  align-items: end;
}

.eyebrow {
  display: inline-flex;
  width: fit-content;
  align-items: center;
  gap: 8px;
  padding: 6px 10px;
  border: 1px solid rgba(255, 90, 54, 0.32);
  border-radius: 999px;
  color: var(--orange-dark);
  background: rgba(255, 255, 255, 0.62);
  font-size: 13px;
  font-weight: 700;
}

.eyebrow::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 0 6px rgba(255, 90, 54, 0.14);
}

.hero h1,
.page-hero h1 {
  margin: 18px 0 18px;
  color: var(--night);
  font-size: clamp(32px, 5.4vw, 58px);
  line-height: 1.02;
}

.hero-copy {
  max-width: 690px;
  color: #334155;
  font-size: 19px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.btn {
  position: relative;
  overflow: hidden;
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border: 1px solid transparent;
  border-radius: 6px;
  font-weight: 800;
  line-height: 1.2;
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, transparent 0%, rgba(255, 255, 255, 0.34) 42%, transparent 72%);
  transform: translateX(-130%);
  transition: transform 0.55s ease;
}

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

.btn:hover::before {
  transform: translateX(130%);
}

.btn:active {
  transform: translateY(0);
}

.btn-primary {
  background: var(--orange);
  color: #fff;
  box-shadow: 0 12px 28px rgba(255, 90, 54, 0.32);
}

.btn-primary:hover {
  background: var(--orange-dark);
}

.btn-secondary {
  border-color: rgba(30, 41, 59, 0.18);
  background: rgba(255, 255, 255, 0.72);
  color: var(--night);
}

.btn-secondary:hover {
  border-color: rgba(255, 90, 54, 0.34);
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 12px 28px rgba(30, 41, 59, 0.12);
}

.hero-panel {
  align-self: stretch;
  display: grid;
  gap: 14px;
  align-content: end;
}

.info-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
}

.metric,
.mini-card,
.card,
.content-block,
.toc,
.faq-item,
.guide-step,
.code-row {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.metric {
  padding: 14px;
}

.metric b {
  display: block;
  color: var(--night);
  font-size: 22px;
  line-height: 1.1;
}

.metric span {
  color: var(--muted);
  font-size: 13px;
}

.preview-shot {
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.7);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.preview-shot:hover {
  transform: translateY(-4px);
  box-shadow: 0 24px 58px rgba(30, 41, 59, 0.18);
}

.preview-shot img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  transition: transform 0.65s ease, filter 0.3s ease;
}

.preview-shot:hover img {
  transform: scale(1.035);
  filter: saturate(1.08);
}

main section,
.page-main {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.section {
  padding: 72px 0;
}

.section.alt {
  width: 100%;
  max-width: none;
  margin: 0;
  background: rgba(255, 255, 255, 0.34);
}

.section.alt > .section-inner {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 24px;
}

.section-head h2 {
  margin: 0;
  color: var(--night);
  font-size: clamp(24px, 3.2vw, 34px);
  line-height: 1.12;
}

.section-head p {
  max-width: 560px;
  margin: 0;
  color: var(--muted);
}

.grid {
  display: grid;
  gap: 18px;
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.card {
  position: relative;
  overflow: hidden;
  padding: 22px;
}

.card::before,
.content-block::before,
.faq-item::before,
.guide-step::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  background: linear-gradient(135deg, rgba(255, 90, 54, 0.12), transparent 42%);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.24s ease;
}

.card:hover,
.metric:hover,
.content-block:hover,
.faq-item:hover,
.guide-step:hover,
.code-row:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 90, 54, 0.28);
  box-shadow: 0 24px 58px rgba(30, 41, 59, 0.17);
}

.card:hover::before,
.content-block:hover::before,
.faq-item:hover::before,
.guide-step:hover::before {
  opacity: 1;
}

.card:hover h3,
.content-block:hover h2,
.content-block:hover h3,
.faq-item:hover h3,
.guide-step:hover h3 {
  color: var(--orange-dark);
}

.card h3,
.content-block h2,
.content-block h3,
.faq-item h3,
.guide-step h3 {
  margin: 0 0 10px;
  color: var(--night);
  line-height: 1.25;
}

.content-block h2 {
  font-size: clamp(22px, 2.6vw, 30px);
}

.card p,
.content-block p,
.faq-item p,
.guide-step p {
  margin: 0;
  color: #475569;
}

.card .tag,
.tag {
  display: inline-flex;
  margin-bottom: 12px;
  padding: 4px 8px;
  border-radius: 999px;
  background: rgba(255, 90, 54, 0.13);
  color: var(--orange-dark);
  font-size: 12px;
  font-weight: 800;
}

.media-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 18px;
  align-items: stretch;
}

.media-grid img {
  width: 100%;
  height: 100%;
  min-height: 250px;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.media-grid img:hover,
.page-hero img:hover,
.gallery img:hover {
  transform: translateY(-4px) scale(1.015);
  filter: saturate(1.08) contrast(1.03);
  box-shadow: 0 24px 58px rgba(30, 41, 59, 0.18);
}

.content-block {
  position: relative;
  overflow: hidden;
  padding: 28px;
}

.list {
  display: grid;
  gap: 12px;
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.list li {
  position: relative;
  padding-left: 24px;
  color: #475569;
}

.list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--orange);
}

.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.78);
}

table {
  width: 100%;
  min-width: 680px;
  border-collapse: collapse;
}

th,
td {
  padding: 14px 16px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}

th {
  color: var(--night);
  background: rgba(30, 41, 59, 0.06);
  font-size: 14px;
}

td {
  color: #475569;
}

tbody tr {
  transition: background 0.2s ease;
}

tbody tr:hover {
  background: rgba(255, 90, 54, 0.07);
}

.page-hero {
  padding: 54px 0 34px;
}

.page-hero .wrap {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(280px, 0.55fr);
  gap: 34px;
  align-items: center;
}

.page-hero p {
  max-width: 720px;
  margin: 0;
  color: #475569;
  font-size: 18px;
}

.page-hero img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 24px;
  padding-bottom: 72px;
}

.content-stack {
  display: grid;
  gap: 20px;
}

.toc {
  position: sticky;
  top: 92px;
  padding: 18px;
  align-self: start;
}

.toc strong {
  display: block;
  margin-bottom: 10px;
  color: var(--night);
}

.toc a {
  display: block;
  padding: 8px 0;
  border-bottom: 1px solid rgba(30, 41, 59, 0.08);
  color: #475569;
  font-size: 14px;
}

.toc a:hover {
  padding-left: 6px;
  color: var(--orange-dark);
}

.code-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  padding: 14px 16px;
}

.code-row code {
  color: var(--night);
  font-size: 18px;
  font-weight: 800;
}

.copy-code {
  min-width: 76px;
  padding: 8px 10px;
  border: 0;
  border-radius: 6px;
  background: var(--night);
  color: #fff;
  cursor: pointer;
}

.copy-code:hover {
  background: var(--orange);
  transform: translateY(-1px);
}

.faq-list,
.steps {
  display: grid;
  gap: 16px;
}

.faq-item,
.guide-step {
  position: relative;
  overflow: hidden;
  padding: 22px;
}

.gallery {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.gallery img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  border-radius: 8px;
  box-shadow: 0 10px 26px rgba(30, 41, 59, 0.12);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}

.site-footer {
  color: rgba(255, 255, 255, 0.78);
  background: var(--night);
}

.footer-inner {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 44px 0 34px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 22px;
  text-align: center;
}

.footer-inner strong {
  display: block;
  color: #fff;
  font-size: 20px;
  line-height: 1.25;
}

.footer-inner span {
  display: block;
  margin-top: 8px;
  color: rgba(255, 255, 255, 0.62);
  font-size: 14px;
}

.friend-links {
  width: 100%;
  display: grid;
  justify-items: center;
  gap: 14px;
  padding: 8px 0 2px;
}

.friend-links h2 {
  margin: 0;
  color: #fff;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.18;
}

.friend-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
}

.friend-list a {
  position: relative;
  display: inline-flex;
  min-height: 42px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 16px 9px 18px;
  border: 1px solid rgba(255, 90, 54, 0.28);
  border-radius: 999px;
  color: rgba(255, 255, 255, 0.9);
  background: rgba(255, 255, 255, 0.07);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.04);
  font-weight: 800;
  line-height: 1.2;
}

.friend-list a::before {
  content: "";
  width: 9px;
  height: 9px;
  border-radius: 50%;
  background: var(--orange);
  box-shadow: 0 0 16px rgba(255, 90, 54, 0.72);
}

.friend-list a:hover {
  transform: translateY(-3px);
  border-color: rgba(255, 90, 54, 0.72);
  color: #fff;
  background: rgba(255, 90, 54, 0.18);
  box-shadow: 0 14px 34px rgba(0, 0, 0, 0.22);
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  font-size: 14px;
}

.footer-links a {
  color: rgba(255, 255, 255, 0.72);
}

.footer-links a:hover {
  color: #fff;
}

.mobile-cta {
  display: none;
}

@media (max-width: 980px) {
  .nav {
    align-items: flex-start;
    flex-direction: column;
    padding: 12px 0;
  }

  .nav-links {
    justify-content: flex-start;
  }

  .hero {
    min-height: auto;
  }

  .hero-inner,
  .page-hero .wrap,
  .page-layout,
  .media-grid {
    grid-template-columns: 1fr;
  }

  .hero-panel {
    align-self: auto;
  }

  .grid-3,
  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .toc {
    position: static;
    order: -1;
  }
}

@media (max-width: 680px) {
  body {
    padding-bottom: 64px;
  }

  .nav-links {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    width: 100%;
  }

  .nav-links a {
    padding: 7px 6px;
    text-align: center;
    font-size: 12px;
  }

  .hero::before {
    background:
      linear-gradient(180deg, rgba(235, 244, 246, 0.97) 0%, rgba(235, 244, 246, 0.88) 52%, rgba(209, 232, 237, 0.62) 100%),
      url("../img/cover.webp") center top / cover no-repeat;
  }

  .hero,
  .section,
  .page-hero {
    padding-top: 38px;
    padding-bottom: 38px;
  }

  .hero h1,
  .page-hero h1 {
    font-size: 32px;
  }

  .hero-copy,
  .page-hero p {
    font-size: 16px;
  }

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

  .section-head,
  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }

  .content-block,
  .card,
  .faq-item,
  .guide-step {
    padding: 18px;
  }

  .actions .btn {
    width: 100%;
  }

  .mobile-cta {
    position: fixed;
    left: 12px;
    right: 12px;
    bottom: 10px;
    z-index: 30;
    display: flex;
    min-height: 48px;
  }
}