/* ========================================
   Article Page Styles
   ======================================== */

.article-hero {
  background: var(--bg-secondary);
  padding: calc(60px + var(--space-md)) var(--space-md) var(--space-md);
  text-align: center;
  border-bottom: 1px solid var(--divider);
}

.article-hero-content {
  max-width: 800px;
  margin: 0 auto;
}

.article-title {
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: var(--space-md);
  line-height: 1.2;
}

.article-meta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
  flex-wrap: wrap;
}

.article-date {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.article-tags {
  display: flex;
  gap: var(--space-xs);
}

.article-tags .tag {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  border: 1px solid var(--divider);
  padding: 0.25rem 0.6rem;
  transition: border-color var(--transition-base);
}

.article-tags .tag:hover {
  border-color: var(--accent);
}

.article-excerpt {
  font-size: 1.1rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.article-container {
  display: flex;
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--space-md) var(--space-md) var(--space-xl);
  gap: var(--space-xl);
}

.article-sidebar {
  width: 280px;
  flex-shrink: 0;
  position: sticky;
  top: calc(var(--space-lg) + 60px);
  height: fit-content;
}

.sidebar-section {
  border-left: 2px solid var(--divider);
  padding-left: var(--space-md);
}

.sidebar-title {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: var(--space-sm);
}

.article-toc {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.article-toc a {
  font-size: 0.85rem;
  color: var(--text-secondary);
  padding: 0.3rem 0;
  transition: color var(--transition-base);
}

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

.article-toc a.active {
  color: var(--accent);
  font-weight: 500;
}

.article-content {
  flex: 1;
  min-width: 0;
}

.markdown-body {
  color: var(--text-primary);
  line-height: 1.8;
}

.markdown-body h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-top: var(--space-xl);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--divider);
}

.markdown-body h2:first-child {
  margin-top: 0;
}

.markdown-body h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
}

.markdown-body p {
  margin-bottom: var(--space-md);
}

.markdown-body ul,
.markdown-body ol {
  margin-bottom: var(--space-md);
  padding-left: var(--space-lg);
}

.markdown-body li {
  margin-bottom: var(--space-sm);
}

.markdown-body strong {
  color: var(--text-primary);
  font-weight: 600;
}

.markdown-body code {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  background: var(--bg-secondary);
  padding: 0.15rem 0.4rem;
  border-radius: 4px;
  color: var(--accent);
}

.markdown-body pre {
  background: var(--bg-secondary);
  border: 1px solid var(--divider);
  border-radius: 8px;
  padding: var(--space-md);
  overflow-x: auto;
  margin: var(--space-md) 0;
}

.markdown-body pre code {
  background: none;
  padding: 0;
  color: var(--text-primary);
  font-size: 0.8rem;
  line-height: 1.6;
}

.markdown-body a {
  color: var(--accent);
  transition: opacity var(--transition-base);
}

.markdown-body a:hover {
  opacity: 0.8;
}

@media (max-width: 1024px) {
  .article-container {
    flex-direction: column;
  }

  .article-sidebar {
    width: 100%;
    position: static;
    order: 2;
  }

  .article-content {
    order: 1;
  }

  .sidebar-section {
    border-left: none;
    border-top: 1px solid var(--divider);
    padding-left: 0;
    padding-top: var(--space-md);
  }

  .article-toc {
    display: flex;
    flex-direction: row;
    flex-wrap: wrap;
    gap: var(--space-sm);
  }

  .article-toc a {
    padding: 0.3rem 0.6rem;
    border: 1px solid var(--divider);
    border-radius: 4px;
  }
}

/* ===== Markdown 扩展元素样式 ===== */

.markdown-body table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-md) 0;
  font-size: 0.9rem;
}

.markdown-body th,
.markdown-body td {
  border: 1px solid var(--divider);
  padding: 0.6rem 0.8rem;
  text-align: left;
}

.markdown-body th {
  background: var(--bg-secondary);
  font-weight: 600;
  color: var(--text-primary);
}

.markdown-body tr:nth-child(even) {
  background: rgba(18, 18, 26, 0.5);
}

.markdown-body blockquote {
  border-left: 3px solid var(--accent);
  background: var(--bg-secondary);
  padding: var(--space-sm) var(--space-md);
  margin: var(--space-md) 0;
  color: var(--text-secondary);
  border-radius: 0 4px 4px 0;
}

.markdown-body blockquote p:last-child {
  margin-bottom: 0;
}

.markdown-body hr {
  border: none;
  border-top: 1px solid var(--divider);
  margin: var(--space-lg) 0;
}

.markdown-body img {
  max-width: 100%;
  border-radius: 8px;
  border: 1px solid var(--divider);
  margin: var(--space-md) 0;
}

.markdown-body h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-top: var(--space-md);
  margin-bottom: var(--space-sm);
  color: var(--text-primary);
}

/* ===== 文章头图 ===== */
.article-hero-image {
  margin: 0 0 var(--space-md) 0;
  text-align: center;
}

.article-hero-image img {
  width: 100%;
  max-width: 800px;
  border-radius: 12px;
  border: 1px solid var(--divider);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
}

/* ===== 文章内联配图 ===== */
.article-inline-image {
  margin: var(--space-lg) 0;
  text-align: center;
}

.article-inline-image img {
  width: 100%;
  max-width: 760px;
  border-radius: 12px;
  border: 1px solid var(--divider);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.3);
}

.article-inline-image figcaption {
  margin-top: var(--space-xs);
  font-size: 0.85rem;
  color: var(--text-secondary);
  font-family: var(--font-mono);
  line-height: 1.5;
}

/* ===== 成本优化四象限图 ===== */
.cost-quadrant {
  position: relative;
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-rows: 1fr 1fr;
  gap: 2px;
  background: var(--divider);
  border: 1px solid var(--divider);
  border-radius: 12px;
  overflow: hidden;
  margin: var(--space-md) 0;
  min-height: 360px;
}

.quadrant {
  background: var(--bg-secondary);
  padding: 1.5rem 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.quadrant-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--accent);
  font-family: var(--font-mono);
  letter-spacing: 0.05em;
}

.quadrant ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.quadrant ul li {
  font-size: 0.85rem;
  color: var(--text-primary);
  padding-left: 1rem;
  position: relative;
  margin: 0;
}

.quadrant ul li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
}

.quadrant-1 {
  background: rgba(0, 240, 255, 0.08);
}

.quadrant-4 {
  background: rgba(0, 240, 255, 0.04);
}

.quadrant-axis {
  position: absolute;
  pointer-events: none;
  z-index: 2;
}

.quadrant-axis-x {
  top: 50%;
  left: 0;
  right: 0;
  transform: translateY(-50%);
  display: flex;
  justify-content: space-between;
  padding: 0 1rem;
}

.quadrant-axis-y {
  left: 50%;
  top: 0;
  bottom: 0;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 1rem 0;
}

.axis-label {
  font-size: 0.75rem;
  font-family: var(--font-mono);
  color: var(--text-secondary);
  background: var(--bg-secondary);
  padding: 0.15rem 0.5rem;
  border-radius: 4px;
  border: 1px solid var(--divider);
}

@media (max-width: 768px) {
  .cost-quadrant {
    min-height: auto;
    grid-template-columns: 1fr;
    grid-template-rows: auto;
  }

  .quadrant-axis {
    display: none;
  }
}

/* ===== 演进路线图 ===== */
.evolution-path {
  display: flex;
  align-items: stretch;
  gap: 0;
  margin: var(--space-md) 0;
  border: 1px solid var(--divider);
  border-radius: 12px;
  overflow: hidden;
}

.path-node {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1.25rem 0.75rem;
  text-align: center;
  position: relative;
  gap: 0.5rem;
  background: var(--bg-secondary);
}

.path-node:not(:last-child)::after {
  content: '';
  position: absolute;
  right: -1px;
  top: 20%;
  height: 60%;
  width: 1px;
  background: linear-gradient(to bottom, transparent, var(--accent), transparent);
  opacity: 0.4;
  z-index: 1;
}

.path-node-1 { background: rgba(18, 18, 26, 0.8); }
.path-node-2 { background: rgba(18, 18, 26, 0.5); }
.path-node-3 { background: rgba(0, 240, 255, 0.06); }
.path-node-4 { background: rgba(0, 240, 255, 0.12); }

.path-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.path-sub {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.path-arrow {
  width: 0;
  height: 0;
  border-left: 6px solid transparent;
  border-right: 6px solid transparent;
  border-bottom: 6px solid var(--accent);
  opacity: 0.3;
}

.path-tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--accent);
  padding: 0.2rem 0.5rem;
  border: 1px solid var(--accent);
  border-radius: 4px;
  opacity: 0.7;
}

.path-result {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.path-node-3 .path-tag,
.path-node-4 .path-tag {
  opacity: 1;
}

@media (max-width: 768px) {
  .evolution-path {
    flex-direction: column;
  }

  .path-node:not(:last-child)::after {
    top: auto;
    bottom: -1px;
    left: 20%;
    right: auto;
    width: 60%;
    height: 1px;
    background: linear-gradient(to right, transparent, var(--accent), transparent);
  }

  .path-arrow {
    transform: rotate(-90deg);
  }
}

/* ===== 数据金字塔 ===== */
.data-pyramid {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
  margin: var(--space-md) 0;
}

.pyramid-layer {
  width: 100%;
  padding: 1rem 1.5rem;
  border: 1px solid var(--divider);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  transition: border-color var(--transition-base);
}

.pyramid-layer:hover {
  border-color: var(--accent);
}

.pyramid-layer-1 {
  max-width: 320px;
  background: rgba(0, 240, 255, 0.12);
  border-radius: 8px;
}

.pyramid-layer-2 {
  max-width: 420px;
  background: rgba(0, 240, 255, 0.09);
}

.pyramid-layer-3 {
  max-width: 520px;
  background: rgba(0, 240, 255, 0.06);
}

.pyramid-layer-4 {
  max-width: 620px;
  background: rgba(0, 240, 255, 0.03);
}

.pyramid-layer-5 {
  max-width: 100%;
  background: rgba(18, 18, 26, 0.5);
}

.pyramid-label {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
}

.pyramid-desc {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
  white-space: nowrap;
}

.pyramid-goal {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent);
  white-space: nowrap;
  padding: 0.2rem 0.6rem;
  border: 1px solid var(--divider);
  border-radius: 4px;
}

@media (max-width: 768px) {
  .pyramid-layer {
    flex-direction: column;
    align-items: flex-start;
    padding: 0.75rem 1rem;
  }

  .pyramid-layer-1,
  .pyramid-layer-2,
  .pyramid-layer-3,
  .pyramid-layer-4,
  .pyramid-layer-5 {
    max-width: 100%;
  }
}

/* ===== Mermaid 图表容器 ===== */
.mermaid {
  background: var(--bg-secondary);
  border: 1px solid var(--divider);
  border-radius: 8px;
  padding: var(--space-md);
  margin: var(--space-md) 0;
  text-align: center;
  overflow-x: auto;
}

/* ===== 图表标题/说明 ===== */
.figure-caption {
  text-align: center;
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: calc(var(--space-sm) * -1);
  margin-bottom: var(--space-md);
}

@media (max-width: 768px) {
  .article-hero {
    padding: calc(60px + var(--space-sm)) var(--space-md) var(--space-sm);
  }

  .article-title {
    font-size: clamp(1.5rem, 4vw, 2.5rem);
  }

  .article-excerpt {
    font-size: 1rem;
  }

  .article-container {
    padding: var(--space-md) var(--space-md) var(--space-lg);
  }

  .markdown-body h2 {
    font-size: 1.3rem;
  }

  .markdown-body h3 {
    font-size: 1.1rem;
  }
}

/* ========================================
   Article Navigation (Prev / Next)
   ======================================== */

.article-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  margin-top: var(--space-xl);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--divider);
}

.article-nav-prev,
.article-nav-next {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  padding: var(--space-md);
  border: 1px solid var(--divider);
  transition: border-color var(--transition-base);
  text-decoration: none;
}

.article-nav-next {
  text-align: right;
  align-items: flex-end;
}

.article-nav-prev:hover,
.article-nav-next:hover {
  border-color: var(--accent);
}

.article-nav-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.article-nav-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

@media (max-width: 768px) {
  .article-nav {
    flex-direction: column;
  }
}

/* ===== 火箭返回顶部按钮 ===== */
.rocket-top-btn {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--bg-secondary);
  border: 1px solid var(--divider);
  color: var(--accent);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  transform: translateY(20px) scale(0.9);
  pointer-events: none;
  transition: opacity 0.4s ease, transform 0.4s ease, border-color 0.3s ease, box-shadow 0.3s ease;
  z-index: 999;
  padding: 0;
}

.rocket-top-btn svg {
  width: 22px;
  height: 22px;
  transition: transform 0.3s ease;
}

.rocket-top-btn.visible {
  opacity: 1;
  transform: translateY(0) scale(1);
  pointer-events: auto;
  animation: rocket-glow 2.5s ease-in-out infinite;
}

.rocket-top-btn:hover {
  border-color: var(--accent);
  box-shadow: 0 0 20px rgba(0, 240, 255, 0.35), 0 0 60px rgba(0, 240, 255, 0.1);
  transform: translateY(-2px) scale(1.05);
}

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

.rocket-top-btn:active {
  transform: translateY(0) scale(0.98);
}

@keyframes rocket-glow {
  0%, 100% {
    box-shadow: 0 0 8px rgba(0, 240, 255, 0.15), 0 0 24px rgba(0, 240, 255, 0.05);
  }
  50% {
    box-shadow: 0 0 16px rgba(0, 240, 255, 0.35), 0 0 40px rgba(0, 240, 255, 0.12);
  }
}

@media (max-width: 768px) {
  .rocket-top-btn {
    bottom: 1.25rem;
    right: 1.25rem;
    width: 44px;
    height: 44px;
  }

  .rocket-top-btn svg {
    width: 20px;
    height: 20px;
  }
}