/* 
  放心云 Sepia Blueprint Theme CSS
  Palette:
  - Parchment: #F7F2E7
  - Dark Sepia: #4A3A30
  - Dusty Blue: #6E8994
  - Pale Sand: #EBE0CE
*/

:root {
  --bg-parchment: #F7F2E7;
  --text-sepia: #4A3A30;
  --dusty-blue: #6E8994;
  --dusty-blue-hover: #5A737D;
  --pale-sand: #EBE0CE;
  --border-sepia: rgba(74, 58, 48, 0.22);
  --border-sepia-strong: #4A3A30;
  --card-bg: #FAF6EE;
  
  --font-serif: "Noto Serif SC", "Source Han Serif SC", "Songti SC", "SimSun", STSong, serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, Courier, monospace;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  
  --h1-desktop: 57px;
  --h1-mobile: 36px;
  --body-size: 17px;
  --line-height-body: 1.68;
  --container-max: 1240px;
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  background-color: var(--bg-parchment);
  color: var(--text-sepia);
  font-family: var(--font-sans);
  font-size: var(--body-size);
  line-height: var(--line-height-body);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  color: var(--text-sepia);
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 0.75rem;
}

h1 {
  font-size: var(--h1-mobile);
  letter-spacing: -0.02em;
}

@media (min-width: 768px) {
  h1 {
    font-size: var(--h1-desktop);
  }
}

h2 {
  font-size: 1.85rem;
  margin-bottom: 1rem;
}

@media (min-width: 768px) {
  h2 {
    font-size: 2.25rem;
  }
}

h3 {
  font-size: 1.35rem;
}

p {
  margin-bottom: 1.15rem;
}

p:last-child {
  margin-bottom: 0;
}

a {
  color: var(--dusty-blue);
  text-decoration: underline;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--text-sepia);
}

.mono-label {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--dusty-blue);
}

.blueprint-tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  background-color: var(--pale-sand);
  border: 1px solid var(--border-sepia);
  color: var(--text-sepia);
  border-radius: 2px;
  margin-bottom: 0.5rem;
}

/* Container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Header Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: var(--bg-parchment);
  border-bottom: 1px solid var(--border-sepia);
  backdrop-filter: blur(8px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.35rem;
  color: var(--text-sepia);
}

.brand-symbol {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  padding: 2px 6px;
  border: 1.5px solid var(--text-sepia);
  background: var(--pale-sand);
}

.nav-desktop {
  display: none;
}

@media (min-width: 992px) {
  .nav-desktop {
    display: flex;
    align-items: center;
    gap: 1.75rem;
  }
}

.nav-link {
  text-decoration: none;
  color: var(--text-sepia);
  font-weight: 500;
  font-size: 0.95rem;
  position: relative;
}

.nav-link:hover {
  color: var(--dusty-blue);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.btn-cta-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  background-color: var(--text-sepia);
  color: var(--bg-parchment);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--border-sepia-strong);
  border-radius: 2px;
  transition: all 0.2s ease;
}

.btn-cta-primary:hover {
  background-color: var(--dusty-blue);
  color: #fff;
  border-color: var(--dusty-blue);
}

.btn-cta-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.65rem 1.4rem;
  background-color: var(--pale-sand);
  color: var(--text-sepia);
  text-decoration: none;
  font-weight: 600;
  font-size: 0.95rem;
  border: 1px solid var(--border-sepia);
  border-radius: 2px;
  transition: all 0.2s ease;
}

.btn-cta-secondary:hover {
  background-color: var(--bg-parchment);
  border-color: var(--text-sepia);
}

/* Mobile Menu Toggle */
.menu-toggle {
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  width: 30px;
  height: 24px;
  background: transparent;
  border: none;
  cursor: pointer;
  padding: 0;
}

@media (min-width: 992px) {
  .menu-toggle {
    display: none;
  }
}

.menu-toggle span {
  width: 100%;
  height: 2px;
  background-color: var(--text-sepia);
  transition: all 0.3s ease;
}

.mobile-nav {
  display: none;
  position: absolute;
  top: 72px;
  left: 0;
  width: 100%;
  background-color: var(--bg-parchment);
  border-bottom: 2px solid var(--text-sepia);
  padding: 1.5rem 1.25rem;
  flex-direction: column;
  gap: 1.25rem;
  box-shadow: 0 10px 25px rgba(0,0,0,0.08);
}

.mobile-nav.open {
  display: flex;
}

.mobile-nav .nav-link {
  font-size: 1.1rem;
  padding: 0.4rem 0;
  border-bottom: 1px dashed var(--border-sepia);
}

/* Hero Section */
.hero-section {
  padding: 3.5rem 0;
  border-bottom: 1px solid var(--border-sepia);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  align-items: center;
}

@media (min-width: 992px) {
  .hero-grid {
    grid-template-columns: 1.1fr 0.9fr;
    gap: 3.5rem;
  }
}

.hero-subhead {
  font-family: var(--font-mono);
  font-size: 0.9rem;
  color: var(--dusty-blue);
  margin-bottom: 1rem;
  display: block;
}

.hero-desc {
  font-size: 1.125rem;
  color: var(--text-sepia);
  margin-bottom: 2rem;
  max-width: 620px;
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 2rem;
}

/* Dashboard Spec / Blueprint Canvas */
.blueprint-dashboard {
  background-color: #F3ECE0;
  border: 1.5px solid var(--text-sepia);
  padding: 1.25rem;
  position: relative;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  box-shadow: 4px 4px 0px rgba(74, 58, 48, 0.15);
}

.dashboard-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-sepia);
  padding-bottom: 0.75rem;
  margin-bottom: 1rem;
}

.dashboard-title {
  font-weight: 700;
  color: var(--text-sepia);
}

.dashboard-disclaimer {
  font-size: 0.72rem;
  color: var(--dusty-blue);
  background: var(--pale-sand);
  padding: 0.2rem 0.5rem;
  border: 1px dashed var(--border-sepia);
}

.blueprint-grid-canvas {
  position: relative;
  border: 1px dashed var(--border-sepia);
  padding: 1rem;
  background-image: 
    linear-gradient(to right, rgba(74, 58, 48, 0.08) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(74, 58, 48, 0.08) 1px, transparent 1px);
  background-size: 20px 20px;
}

.measured-line {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.6rem 0;
  border-bottom: 1px dotted var(--border-sepia);
}

.measured-label {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.node-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--dusty-blue);
  border: 1px solid var(--text-sepia);
}

.measured-guide {
  font-size: 0.75rem;
  color: var(--dusty-blue);
}

/* Numbered Callouts & Open-Column Benefits */
.section-padding {
  padding: 4rem 0;
}

.section-header {
  margin-bottom: 3rem;
}

.section-title {
  font-family: var(--font-serif);
  font-size: 2rem;
  color: var(--text-sepia);
}

.open-columns-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 768px) {
  .open-columns-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 2.5rem;
  }
}

.open-column-card {
  border-top: 2px solid var(--text-sepia);
  padding-top: 1.25rem;
}

.callout-num {
  font-family: var(--font-mono);
  font-size: 2.25rem;
  font-weight: 700;
  color: var(--dusty-blue);
  line-height: 1;
  margin-bottom: 0.75rem;
}

.column-title {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
}

.column-desc {
  font-size: 0.95rem;
  color: var(--text-sepia);
}

/* Restrained Crosshatch CSS Texture Section (Nodes Route Diagram) */
.crosshatch-bg {
  background-color: var(--bg-parchment);
  background-image: 
    linear-gradient(45deg, rgba(74, 58, 48, 0.04) 25%, transparent 25%), 
    linear-gradient(-45deg, rgba(74, 58, 48, 0.04) 25%, transparent 25%), 
    linear-gradient(45deg, transparent 75%, rgba(74, 58, 48, 0.04) 75%), 
    linear-gradient(-45deg, transparent 75%, rgba(74, 58, 48, 0.04) 75%);
  background-size: 24px 24px;
  background-position: 0 0, 0 12px, 12px -12px, -12px 0px;
  border-top: 1px solid var(--border-sepia);
  border-bottom: 1px solid var(--border-sepia);
}

.route-diagram-wrapper {
  background-color: var(--card-bg);
  border: 1.5px solid var(--text-sepia);
  padding: 1.5rem;
  margin-top: 2rem;
}

.route-svg-container {
  width: 100%;
  max-width: 900px;
  margin: 0 auto;
}

.route-path {
  fill: none;
  stroke: var(--dusty-blue);
  stroke-width: 2.5;
  stroke-linecap: round;
  stroke-dasharray: 600;
  stroke-dashoffset: 600;
  transition: stroke-dashoffset 2.2s ease-in-out;
}

.route-path.animated {
  stroke-dashoffset: 0;
}

@media (prefers-reduced-motion: reduce) {
  .route-path {
    stroke-dashoffset: 0;
    transition: none;
  }
}

.node-list-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-top: 1.5rem;
}

@media (min-width: 768px) {
  .node-list-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.node-item-card {
  background: var(--bg-parchment);
  border: 1px solid var(--border-sepia);
  padding: 1rem;
  text-align: center;
  font-family: var(--font-mono);
}

.node-item-code {
  font-weight: 700;
  color: var(--dusty-blue);
}

.node-item-name {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  margin-top: 0.25rem;
}

/* AI & Streaming Use Cases Grid */
.cases-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .cases-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .cases-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.case-card {
  background-color: var(--card-bg);
  border: 1px solid var(--border-sepia);
  padding: 1.5rem;
  transition: transform 0.2s ease, border-color 0.2s ease;
}

.case-card:hover {
  border-color: var(--text-sepia);
  transform: translateY(-2px);
}

.case-category {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--dusty-blue);
  margin-bottom: 0.5rem;
}

.case-title {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
}

.case-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 1rem;
}

.case-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 2px 6px;
  background: var(--pale-sand);
  border: 1px solid var(--border-sepia);
  border-radius: 2px;
}

/* Pricing Specification Table */
.pricing-section {
  border-top: 1px solid var(--border-sepia);
}

.table-responsive {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin-top: 1.5rem;
  border: 1.5px solid var(--text-sepia);
}

.spec-table {
  width: 100%;
  border-collapse: collapse;
  background-color: var(--card-bg);
  text-align: left;
  font-size: 0.95rem;
}

.spec-table th, .spec-table td {
  padding: 1rem 1.25rem;
  border: 1px solid var(--border-sepia);
}

.spec-table th {
  background-color: var(--pale-sand);
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--text-sepia);
}

.spec-table tr:nth-child(even) {
  background-color: rgba(235, 224, 206, 0.25);
}

.placeholder-text {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: #8C7565;
  background: rgba(74, 58, 48, 0.06);
  padding: 2px 6px;
  border-radius: 2px;
  display: inline-block;
}

/* 9 Article Cards (Manual Chapter Format) Grid */
/* 3 desktop / 2 tablet / 1 mobile */
.articles-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.75rem;
  margin-top: 2rem;
}

@media (min-width: 640px) {
  .articles-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .articles-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.manual-card {
  background-color: var(--card-bg);
  border: 1px solid var(--text-sepia);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  position: relative;
  box-shadow: 2px 2px 0px rgba(74, 58, 48, 0.1);
  transition: all 0.2s ease;
}

.manual-card:hover {
  box-shadow: 4px 4px 0px rgba(74, 58, 48, 0.2);
  transform: translateY(-2px);
}

.chapter-code {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--dusty-blue);
  border-bottom: 1px dashed var(--border-sepia);
  padding-bottom: 0.5rem;
  margin-bottom: 0.75rem;
}

.chapter-title {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  margin-bottom: 0.75rem;
}

.chapter-title a {
  color: var(--text-sepia);
  text-decoration: none;
}

.chapter-title a:hover {
  color: var(--dusty-blue);
}

.chapter-excerpt {
  font-size: 0.9rem;
  color: var(--text-sepia);
  margin-bottom: 1.25rem;
  flex-grow: 1;
}

.read-more-link {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--dusty-blue);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}

.read-more-link:hover {
  text-decoration: underline;
}

/* Testimonials Section */
.testimonials-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin-top: 2rem;
}

@media (min-width: 768px) {
  .testimonials-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.testimonial-card {
  background: var(--card-bg);
  border: 1px solid var(--border-sepia);
  padding: 1.5rem;
  position: relative;
}

.testimonial-quote {
  font-style: italic;
  font-size: 0.95rem;
  margin-bottom: 1rem;
}

.testimonial-author {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--dusty-blue);
  border-top: 1px dotted var(--border-sepia);
  padding-top: 0.5rem;
}

.sample-badge {
  display: inline-block;
  font-size: 0.7rem;
  font-family: var(--font-mono);
  background: var(--pale-sand);
  padding: 1px 5px;
  border: 1px solid var(--border-sepia);
  margin-left: 0.5rem;
}

/* FAQ Section */
.faq-grid {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 2rem;
}

.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--border-sepia);
  padding: 1.25rem 1.5rem;
}

.faq-question {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-sepia);
  margin-bottom: 0.5rem;
}

.faq-answer {
  font-size: 0.95rem;
  color: var(--text-sepia);
}

/* Breadcrumbs */
.breadcrumb-nav {
  margin-bottom: 1.5rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  list-style: none;
}

.breadcrumb-item a {
  color: var(--dusty-blue);
  text-decoration: none;
}

.breadcrumb-item a:hover {
  text-decoration: underline;
}

.breadcrumb-item::after {
  content: "/";
  margin-left: 0.5rem;
  color: var(--border-sepia-strong);
}

.breadcrumb-item:last-child::after {
  content: "";
}

.breadcrumb-item.active {
  color: var(--text-sepia);
}

/* Article & Content Page Styles */
.article-container {
  max-width: 860px;
  margin: 0 auto;
  padding: 3rem 1.25rem;
}

.article-header {
  border-bottom: 2px solid var(--text-sepia);
  padding-bottom: 1.5rem;
  margin-bottom: 2rem;
}

.article-meta {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--dusty-blue);
  margin-bottom: 0.75rem;
}

.article-body {
  font-size: 1.05rem;
  line-height: 1.8;
}

.article-body h2 {
  margin-top: 2.25rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--border-sepia);
  padding-bottom: 0.4rem;
}

.article-body h3 {
  margin-top: 1.75rem;
  margin-bottom: 0.75rem;
}

.article-body ul, .article-body ol {
  margin-left: 1.5rem;
  margin-bottom: 1.25rem;
}

.article-body li {
  margin-bottom: 0.4rem;
}

.article-body blockquote {
  border-left: 3px solid var(--dusty-blue);
  background: var(--pale-sand);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  font-style: italic;
}

.related-articles {
  margin-top: 3.5rem;
  border-top: 2px solid var(--text-sepia);
  padding-top: 2rem;
}

/* Footer */
.site-footer {
  background-color: #EDE4D3;
  border-top: 2px solid var(--text-sepia);
  padding: 4rem 0 2rem 0;
  margin-top: 4rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2.5rem;
  margin-bottom: 3rem;
}

@media (min-width: 768px) {
  .footer-grid {
    grid-template-columns: 2fr 1fr 1fr;
  }
}

.footer-brand {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
}

.footer-desc {
  font-size: 0.9rem;
  color: var(--text-sepia);
  max-width: 400px;
}

.footer-title {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  text-transform: uppercase;
  color: var(--dusty-blue);
  margin-bottom: 1rem;
  font-weight: 700;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.footer-links a {
  color: var(--text-sepia);
  text-decoration: none;
  font-size: 0.9rem;
}

.footer-links a:hover {
  color: var(--dusty-blue);
  text-decoration: underline;
}

.footer-bottom {
  border-top: 1px solid var(--border-sepia);
  padding-top: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  align-items: center;
  text-align: center;
  font-size: 0.85rem;
  font-family: var(--font-mono);
}

@media (min-width: 768px) {
  .footer-bottom {
    flex-direction: row;
    justify-content: space-between;
  }
}