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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: #ffffff;
  color: #1a1a1a;
  line-height: 1.6;
  padding: 40px 20px;
  transition: background-color 0.3s ease, color 0.3s ease;
}

html.dark-mode body,
body.dark-mode {
  background: #1a1a1a;
  color: #e0e0e0;
}

html.dark-mode header,
body.dark-mode header {
  border-bottom-color: #333;
}

html.dark-mode header h1,
html.dark-mode .section h2,
html.dark-mode .writeup-card h3,
body.dark-mode header h1,
body.dark-mode .section h2,
body.dark-mode .writeup-card h3 {
  color: #e0e0e0;
}

html.dark-mode .back-link,
html.dark-mode .date,
html.dark-mode .description,
body.dark-mode .back-link,
body.dark-mode .date,
body.dark-mode .description {
  color: #999;
}

html.dark-mode .back-link:hover,
body.dark-mode .back-link:hover {
  color: #e0e0e0;
}

html.dark-mode .section h2,
body.dark-mode .section h2 {
  border-bottom-color: #333;
}

html.dark-mode .writeup-card,
body.dark-mode .writeup-card {
  border-color: #333;
}

html.dark-mode .writeup-card:hover,
body.dark-mode .writeup-card:hover {
  border-color: #555;
  background-color: #222;
}

html.dark-mode .tag,
body.dark-mode .tag {
  border-color: #444;
}

html.dark-mode .article-reader,
body.dark-mode .article-reader {
  background: #1a1a1a;
}

body.dark-mode .reader-header {
  border-bottom-color: #333;
  background: #222;
}

body.dark-mode .close-btn {
  border-color: #555;
  color: #999;
}

body.dark-mode .close-btn:hover {
  border-color: #e0e0e0;
  color: #e0e0e0;
}

body.dark-mode .reader-header h2 {
  color: #e0e0e0;
}

body.dark-mode .reader-meta {
  color: #999;
}

body.dark-mode .toc {
  border-right-color: #333;
  background: #222;
}

body.dark-mode .toc h3 {
  color: #e0e0e0;
  border-bottom-color: #333;
}

body.dark-mode .toc-item {
  color: #999;
}

body.dark-mode .toc-item:hover,
body.dark-mode .toc-item.active {
  color: #e0e0e0;
  border-left-color: #e0e0e0;
}

body.dark-mode .reader-content h1,
body.dark-mode .reader-content h2,
body.dark-mode .reader-content h3,
body.dark-mode .reader-content strong {
  color: #e0e0e0;
}

body.dark-mode .reader-content h1 {
  border-bottom-color: #333;
}

body.dark-mode .reader-content p,
body.dark-mode .reader-content li {
  color: #ccc;
}

body.dark-mode .reader-content code {
  background: #2a2a2a;
  border-color: #444;
}

body.dark-mode .reader-content pre {
  background: #2a2a2a;
  border-color: #444;
}

body.dark-mode .copy-btn {
  background: #333;
  border-color: #555;
  color: #999;
}

body.dark-mode .copy-btn:hover {
  border-color: #777;
  color: #e0e0e0;
}

body.dark-mode .reader-content img {
  border-color: #444;
}

body.dark-mode .reader-content blockquote {
  border-left-color: #444;
  color: #999;
}

body.dark-mode .image-placeholder {
  border-color: #444;
  color: #666;
}

body.dark-mode ::-webkit-scrollbar-track {
  background: #2a2a2a;
}

body.dark-mode ::-webkit-scrollbar-thumb {
  background: #555;
}

body.dark-mode ::-webkit-scrollbar-thumb:hover {
  background: #666;
}

.container {
  max-width: 900px;
  margin: 0 auto;
}

header {
  margin-bottom: 60px;
  padding-bottom: 30px;
  border-bottom: 1px solid #e0e0e0;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  color: #1a1a1a;
}

.back-link {
  text-decoration: none;
  color: #666;
  font-size: 0.95rem;
  transition: color 0.2s ease;
}

.back-link:hover {
  color: #1a1a1a;
}

.section {
  margin-bottom: 60px;
}

.section h2 {
  font-size: 1.8rem;
  font-weight: 600;
  color: #1a1a1a;
  margin-bottom: 30px;
  padding-bottom: 10px;
  border-bottom: 1px solid #e0e0e0;
}

.writeup-card {
  padding: 30px;
  border: 1px solid #e0e0e0;
  cursor: pointer;
  transition: border-color 0.2s ease, background-color 0.2s ease;
}

.writeup-card:hover {
  border-color: #999;
  background-color: #fafafa;
}

.writeup-card h3 {
  font-size: 1.4rem;
  font-weight: 600;
  color: #1a1a1a;
  margin-bottom: 12px;
}

.meta {
  display: flex;
  gap: 10px;
  margin-bottom: 15px;
  flex-wrap: wrap;
}

.meta {
  margin: 25px 0 12px 0;
}

.reader-content p {
  margin: 15px 0;
  color: #333;
  line-height: 1.8;
}

.reader-content a {
  color: #1a1a1a;
  text-decoration: underline;
  transition: opacity 0.2s ease;
}

.reader-content a:hover {
  opacity: 0.7;
}

.reader-content strong {
  font-weight: 600;
  color: #1a1a1a;
}

.reader-content em {
  font-style: italic;
}

.reader-content code {
  font-family: 'Fira Code', 'Monaco', 'Courier New', monospace;
  background: #f5f5f5;
  padding: 2px 6px;
  font-size: 0.9em;
  border: 1px solid #e0e0e0;
}

.reader-content pre {
  background: #f5f5f5;
  border: 1px solid #e0e0e0;
  padding: 20px;
  margin: 20px 0;
  overflow-x: auto;
  position: relative;
}

.reader-content pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.85rem;
  line-height: 1.6;
  display: block;
}

.copy-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  background: #ffffff;
  border: 1px solid #ccc;
  color: #666;
  padding: 4px 10px;
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.2s ease;
}

.copy-btn:hover {
  border-color: #999;
  color: #1a1a1a;
}

.reader-content ul,
.reader-content ol {
  margin: 15px 0;
  padding-left: 30px;
}

.reader-content li {
  margin: 8px 0;
  color: #333;
  line-height: 1.7;
}

.reader-content img {
  max-width: 100%;
  height: auto;
  margin: 25px 0;
  border: 1px solid #e0e0e0;
}

.reader-content blockquote {
  border-left: 3px solid #e0e0e0;
  padding-left: 20px;
  margin: 20px 0;
  color: #666;
  font-style: italic;
}

.image-placeholder {
  padding: 40px;
  text-align: center;
  color: #999;
  border: 1px dashed #ccc;
  margin: 25px 0;
}

/* ========== Scrollbar ========== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: #f5f5f5;
}

::-webkit-scrollbar-thumb {
  background: #ccc;
}

::-webkit-scrollbar-thumb:hover {
  background: #999;
}

/* ========== 響應式設計 ========== */
@media (max-width: 768px) {
  body {
    padding: 20px 15px;
  }

  header {
    flex-direction: column;
    align-items: flex-start;
    gap: 15px;
  }

  header h1 {
    font-size: 2rem;
  }

  .writeup-card {
    padding: 20px;
  }

  .reader-header {
    padding: 20px;
  }

  .reader-header h2 {
    font-size: 1.5rem;
  }

  .toc {
    display: none;
  }

  .reader-content {
    padding: 20px;
  }

  .reader-content h1 {
    font-size: 1.8rem;
  }

  .reader-content h2 {
    font-size: 1.4rem;
  }

  .reader-content h3 {
    font-size: 1.2rem;
  }

  .reader-content pre {
    padding: 15px;
    margin: 15px -10px;
  }
}

.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  background: none;
  border: 1px solid #e0e0e0;
  padding: 10px 15px;
  cursor: pointer;
  font-size: 1.2rem;
  transition: all 0.2s ease;
  z-index: 1000;
}

.theme-toggle:hover {
  border-color: #1a1a1a;
  background: #fafafa;
}

body.dark-mode .theme-toggle {
  border-color: #333;
}

body.dark-mode .theme-toggle:hover {
  border-color: #666;
  background: #222;
}

/* ========== Callout Blocks ========== */
.callout {
  margin: 20px 0;
  padding: 15px 20px;
  border-left: 4px solid;
  border-radius: 4px;
  background: #f8f9fa;
}

.callout-content {
  font-size: 0.95rem;
  line-height: 1.6;
}

.callout-content p:first-child {
  margin-top: 0;
}

.callout-content p:last-child {
  margin-bottom: 0;
}

.callout-success {
  border-left-color: #22c55e;
  background: #f0fdf4;
  color: #16a34a;
}

.callout-info {
  border-left-color: #3b82f6;
  background: #eff6ff;
  color: #2563eb;
}

.callout-warning {
  border-left-color: #f59e0b;
  background: #fffbeb;
  color: #d97706;
}

.callout-danger {
  border-left-color: #ef4444;
  background: #fef2f2;
  color: #dc2626;
}

.callout-note,
.callout-tip {
  border-left-color: #8b5cf6;
  background: #faf5ff;
  color: #7c3aed;
}

/* Dark mode callouts */
html.dark-mode .callout,
body.dark-mode .callout {
  background: #1f2937;
}

html.dark-mode .callout-success,
body.dark-mode .callout-success {
  background: rgba(34, 197, 94, 0.1);
  color: #4ade80;
}

html.dark-mode .callout-info,
body.dark-mode .callout-info {
  background: rgba(59, 130, 246, 0.1);
  color: #60a5fa;
}

html.dark-mode .callout-warning,
body.dark-mode .callout-warning {
  background: rgba(245, 158, 11, 0.1);
  color: #fbbf24;
}

html.dark-mode .callout-danger,
body.dark-mode .callout-danger {
  background: rgba(239, 68, 68, 0.1);
  color: #f87171;
}

html.dark-mode .callout-note,
html.dark-mode .callout-tip,
body.dark-mode .callout-note,
body.dark-mode .callout-tip {
  background: rgba(139, 92, 246, 0.1);
  color: #a78bfa;
}

/* ========== 螢光筆標記 ========== */
mark {
  background: #fef08a;
  color: #1a1a1a;
  padding: 2px 4px;
  border-radius: 2px;
}

html.dark-mode mark,
body.dark-mode mark {
  background: #854d0e;
  color: #fef08a;
}

/* ========== 分隔線 ========== */
.reader-content hr {
  border: none;
  border-top: 1px solid #e0e0e0;
  margin: 30px 0;
}

html.dark-mode .reader-content hr,
body.dark-mode .reader-content hr {
  border-top-color: #333;
}

/* ========== 暴雷內容 ========== */
.spoiler {
  background: #1a1a1a;
  color: #1a1a1a;
  padding: 2px 4px;
  border-radius: 2px;
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
}

.spoiler:hover,
.spoiler.revealed {
  background: #fef08a;
  color: #1a1a1a;
}

html.dark-mode .spoiler,
body.dark-mode .spoiler {
  background: #e0e0e0;
  color: #e0e0e0;
}

html.dark-mode .spoiler:hover,
html.dark-mode .spoiler.revealed,
body.dark-mode .spoiler:hover,
body.dark-mode .spoiler.revealed {
  background: #854d0e;
  color: #fef08a;
}

.callout-spoiler {
  border-left-color: #6b7280;
  background: #f9fafb;
}

.callout-spoiler summary {
  cursor: pointer;
  user-select: none;
  list-style: none;
  font-weight: 600;
  color: #6b7280;
  padding: 5px 0;
}

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

.callout-spoiler summary::before {
  content: '▶ ';
  display: inline-block;
  transition: transform 0.2s ease;
}

.callout-spoiler[open] summary::before {
  transform: rotate(90deg);
}

.callout-spoiler .callout-content {
  margin-top: 8px;
}

html.dark-mode .callout-spoiler,
body.dark-mode .callout-spoiler {
  background: rgba(107, 114, 128, 0.1);
}

html.dark-mode .callout-spoiler summary,
body.dark-mode .callout-spoiler summary {
  color: #9ca3af;
}