:root {
  --paper: #fffaf3;
  --paper-alt: #fffefb;
  --line: #eadfce;
  --ink: #1f1a16;
  --ink-soft: #6d6458;
  --accent: #c7352f;
  --accent-deep: #96221d;
  --accent-soft: #fdecea;
  --ok: #1b8b57;
  --dark: #201a16;
  --radius: 10px;
  --shadow: 0 14px 28px rgba(32, 26, 22, 0.08);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  color: var(--ink);
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  line-height: 1.72;
  background:
    radial-gradient(circle at 0% 0%, rgba(199, 53, 47, 0.08), transparent 38%),
    radial-gradient(circle at 100% 0%, rgba(255, 204, 153, 0.18), transparent 42%),
    repeating-linear-gradient(90deg, transparent, transparent 34px, rgba(234, 223, 206, 0.25) 34px, rgba(234, 223, 206, 0.25) 35px),
    var(--paper);
}

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

h1,
h2,
h3 {
  font-family: "Noto Serif SC", "Source Han Serif SC", "STSong", "SimSun", serif;
  letter-spacing: 0.2px;
}

.container {
  width: min(1120px, calc(100% - 38px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(255, 250, 243, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
  border-top: 4px solid var(--accent);
}

.header-row {
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 700;
}

.logo svg {
  width: 31px;
  height: 31px;
}

.logo small {
  display: block;
  color: var(--ink-soft);
  font-weight: 500;
  font-size: 12px;
  margin-top: 1px;
}

.site-nav {
  display: inline-flex;
  gap: 16px;
  align-items: center;
  font-size: 15px;
  font-weight: 700;
}

.site-nav a {
  color: #5e5549;
  padding-bottom: 4px;
  border-bottom: 2px solid transparent;
  transition: all 0.2s ease;
}

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

.page-home .nav-home,
.page-download .nav-download,
.page-zh .nav-zh {
  color: var(--accent);
  border-color: var(--accent);
}

.main {
  padding-top: 42px;
}

.lead {
  display: grid;
  grid-template-columns: 1.18fr 0.82fr;
  gap: 18px;
  align-items: stretch;
}

.panel,
.card,
.quote,
.details details,
.note-box,
.table-box,
.cta,
.toc {
  background: var(--paper-alt);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.label {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 999px;
  border: 1px solid #f3c9c5;
  color: #8d2b25;
  background: var(--accent-soft);
  font-size: 13px;
  font-weight: 700;
}

.label svg {
  width: 15px;
  height: 15px;
}

.lead h1 {
  margin: 14px 0 0;
  font-size: clamp(30px, 4vw, 48px);
  line-height: 1.24;
}

.lead p {
  margin-top: 14px;
  margin-bottom: 0;
  color: var(--ink-soft);
  font-size: 17px;
}

.actions {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.btn {
  border: 1px solid transparent;
  padding: 11px 18px;
  border-radius: 7px;
  font-size: 15px;
  font-weight: 700;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn:disabled {
  opacity: 0.9;
  cursor: not-allowed;
}

.btn svg {
  width: 18px;
  height: 18px;
}

.btn-primary {
  color: #fff;
  border-color: var(--accent-deep);
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  box-shadow: 0 10px 20px rgba(150, 34, 29, 0.28);
}

.btn-secondary {
  color: #8c2b25;
  border-color: #f0b5af;
  background: #ffecea;
}

.btn-line {
  color: #3f342a;
  border-color: #d8c9b6;
  background: #fff;
}

.panel {
  padding: 18px;
}

.panel h2 {
  margin: 0;
  font-size: 22px;
}

.quick-buttons {
  margin-top: 14px;
  display: grid;
  gap: 10px;
}

.quick-buttons .btn {
  width: 100%;
}

.mini-tip {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed #e7d9c7;
  color: #6f6458;
  font-size: 13px;
}

.section {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 2px solid #f0e5d4;
}

.section-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
}

.section-head h2 {
  margin: 0;
  font-size: clamp(24px, 2.4vw, 35px);
}

.section-head p {
  margin: 7px 0 0;
  color: var(--ink-soft);
}

.mark {
  font-size: 12px;
  font-weight: 700;
  color: #7d7265;
  letter-spacing: 1px;
  text-transform: uppercase;
  border: 1px solid #dfd2bf;
  padding: 6px 10px;
  border-radius: 999px;
  white-space: nowrap;
}

.route-grid {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.route {
  border: 1px solid var(--line);
  background: #fffdf8;
  border-radius: 8px;
  padding: 16px;
  position: relative;
}

.route::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(to bottom, var(--accent), #f2a36e);
  border-radius: 8px 0 0 8px;
}

.route h3 {
  margin: 0;
  font-size: 18px;
}

.route p {
  margin: 8px 0 0;
  color: #5f564a;
  font-size: 14px;
}

.feature-stack {
  margin-top: 18px;
  display: grid;
  gap: 12px;
}

.feature-row {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 8px;
  align-items: stretch;
}

.feature-copy {
  padding: 16px;
}

.feature-copy h3 {
  margin: 0;
  font-size: 21px;
}

.feature-copy p {
  margin: 8px 0 0;
  color: #5d5347;
}

.feature-meta {
  margin-top: 10px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.feature-meta span {
  font-size: 12px;
  border: 1px solid #e7d9c7;
  color: #6a5f52;
  padding: 4px 8px;
  border-radius: 999px;
}

.feature-visual {
  border-left: 1px dashed #eadfce;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
}

.feature-visual svg {
  width: 88px;
  height: 88px;
  color: var(--accent);
}

.download-table {
  margin-top: 16px;
}

.table-box {
  overflow-x: auto;
}

table {
  width: 100%;
  min-width: 640px;
  border-collapse: collapse;
}

th,
td {
  padding: 12px 14px;
  border-bottom: 1px solid #eee3d3;
  text-align: left;
  font-size: 14px;
}

th {
  color: #3d3329;
  background: #fdf3e8;
}

td {
  color: #5f5549;
}

.review-wrap {
  margin-top: 16px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 12px;
}

.quote {
  padding: 16px;
  display: grid;
  grid-template-columns: 34px 1fr;
  gap: 12px;
}

.quote svg {
  width: 28px;
  height: 28px;
  color: var(--accent);
}

.quote p {
  margin: 0;
  color: #4f4539;
}

.quote b {
  display: block;
  margin-top: 8px;
  font-size: 14px;
}

.details {
  margin-top: 16px;
  display: grid;
  gap: 10px;
}

.details details {
  overflow: hidden;
}

.details summary {
  list-style: none;
  cursor: pointer;
  padding: 14px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  color: #3a3128;
}

.details summary::-webkit-details-marker {
  display: none;
}

.details summary svg {
  width: 16px;
  height: 16px;
  color: #6f6356;
  transition: transform 0.2s ease;
}

.details details[open] summary svg {
  transform: rotate(180deg);
}

.detail-body {
  padding: 12px 16px 16px;
  border-top: 1px dashed #ebdecd;
  color: #5f564a;
  font-size: 14px;
}

.download-layout {
  margin-top: 16px;
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 14px;
  align-items: start;
}

.sticky-nav {
  position: sticky;
  top: 92px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fffdf8;
  padding: 12px;
}

.sticky-nav h3 {
  margin: 0 0 8px;
  font-size: 17px;
}

.sticky-nav a {
  display: block;
  padding: 8px 0;
  color: #6a5f52;
  border-bottom: 1px dashed #ecdfcf;
  font-size: 14px;
}

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

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

.content-flow {
  display: grid;
  gap: 12px;
}

.note-box {
  padding: 16px;
}

.note-box h3 {
  margin: 0;
  font-size: 21px;
}

.note-box p {
  margin: 8px 0 0;
  color: #61574b;
}

.bullets {
  margin: 10px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.bullets li {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  color: #5b5145;
}

.bullets li svg {
  width: 16px;
  height: 16px;
  color: var(--ok);
  margin-top: 5px;
  flex-shrink: 0;
}

.steps {
  margin: 10px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 8px;
}

.steps li {
  display: grid;
  grid-template-columns: 28px 1fr;
  gap: 10px;
}

.step-no {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  color: #fff;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 700;
  margin-top: 2px;
}

.toc {
  margin-top: 16px;
  padding: 16px;
}

.toc h3 {
  margin: 0;
  font-size: 20px;
}

.toc-grid {
  margin-top: 10px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.toc-grid a {
  font-size: 14px;
  color: #6a5f52;
  border: 1px solid #e5d8c6;
  border-radius: 6px;
  padding: 8px 10px;
}

.toc-grid a:hover {
  color: var(--accent);
  border-color: #e7b7b3;
  background: #fff5f3;
}

.article-stack {
  margin-top: 14px;
  display: grid;
  gap: 12px;
}

.cta {
  margin-top: 16px;
  padding: 24px;
  text-align: center;
  background:
    linear-gradient(145deg, rgba(199, 53, 47, 0.1), rgba(244, 164, 96, 0.1)),
    #fff;
}

.cta h2 {
  margin: 0;
  font-size: 30px;
}

.cta p {
  margin-top: 8px;
  margin-bottom: 0;
  color: #655c50;
}

.cta .btn {
  margin-top: 14px;
}

.site-footer {
  margin-top: 54px;
  border-top: 1px solid var(--line);
  padding: 26px 0 34px;
  text-align: center;
  color: #62584c;
  font-size: 14px;
}

.site-footer .safe-line {
  margin-bottom: 8px;
  color: #3b3128;
  font-weight: 700;
}

@keyframes spin {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

@media (max-width: 980px) {
  .lead,
  .feature-row,
  .download-layout,
  .route-grid,
  .toc-grid {
    grid-template-columns: 1fr 1fr;
  }

  .download-layout {
    grid-template-columns: 1fr;
  }

  .sticky-nav {
    position: static;
  }

  .feature-visual {
    border-left: none;
    border-top: 1px dashed #eadfce;
  }

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

@media (max-width: 760px) {
  .container {
    width: min(1120px, calc(100% - 24px));
  }

  .header-row {
    min-height: 68px;
    flex-direction: column;
    justify-content: center;
    padding: 10px 0;
  }

  .site-nav {
    width: 100%;
    justify-content: space-between;
    gap: 8px;
  }

  .site-nav a {
    flex: 1;
    text-align: center;
  }

  .lead,
  .feature-row,
  .route-grid,
  .toc-grid {
    grid-template-columns: 1fr;
  }

  .actions .btn,
  .quick-buttons .btn {
    width: 100%;
  }

  .cta h2 {
    font-size: 25px;
  }
}