@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap');

:root {
  /* Ultra-minimalist Monochrome Palette (Vercel/Apple Style) */
  --bg: #ffffff;
  --fg: #111111;
  --gray-50: #fafafa;
  --gray-100: #f5f5f5;
  --gray-200: #eaeaea;
  --gray-300: #d4d4d4;
  --gray-400: #a3a3a3;
  --gray-500: #737373;
  --gray-600: #525252;
  --gray-800: #262626;
  --gray-900: #171717;
  
  --accent: #0070f3; /* High-contrast tech blue */
  --accent-light: rgba(0, 112, 243, 0.1);
  
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", Consolas, Menlo, monospace;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  background-color: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  line-height: 1.6;
  font-size: 16px;
}

/* Global Layout */
.app-wrapper {
  max-width: 1040px;
  margin: 0 auto;
  padding: 80px 24px;
  display: flex;
  gap: 80px;
}

@media (max-width: 768px) {
  .app-wrapper {
    flex-direction: column;
    padding: 40px 20px;
    gap: 48px;
  }
}

/* --- Sleek Sidebar --- */
.sidebar {
  width: 240px;
  flex-shrink: 0;
  position: sticky;
  top: 80px;
}

.profile {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.avatar {
  width: 88px;
  height: 88px;
  border-radius: 50%;
  object-fit: cover;
  border: 1px solid var(--gray-200);
  transition: transform 0.3s ease, filter 0.3s ease;
  filter: grayscale(10%);
}

.avatar:hover {
  transform: scale(1.02);
  filter: grayscale(0%);
}

.author-name {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0;
  letter-spacing: -0.02em;
  color: var(--gray-900);
}

.author-bio {
  font-size: 0.95rem;
  color: var(--gray-500);
  margin: 0;
  line-height: 1.5;
}

.social-links {
  display: flex;
  gap: 16px;
  margin-top: 8px;
}

.social-links a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.9rem;
  color: var(--gray-500);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.social-links a:hover {
  color: var(--fg);
}

.social-links svg {
  width: 18px;
  height: 18px;
}

/* --- Main Content Area --- */
.main-content {
  flex: 1;
  min-width: 0;
}

.section-title {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--gray-900);
  margin: 0 0 24px 0;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--gray-200);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* Post List */
.post-list {
  display: flex;
  flex-direction: column;
}

.post-item {
  padding: 24px 16px;
  margin: 0 -16px; /* Bleed out padding */
  border-radius: 12px;
  display: block;
  text-decoration: none;
  color: inherit;
  transition: background 0.2s ease, transform 0.2s ease;
  position: relative;
}

/* Bottom separator logic */
.post-item::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 16px;
  right: 16px;
  height: 1px;
  background-color: var(--gray-200);
  transition: background-color 0.2s ease;
}

.post-item:last-child::after {
  display: none;
}

.post-item:hover {
  background: var(--gray-50);
}

.post-item:hover::after {
  background-color: transparent;
}

.post-title {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0 0 8px 0;
  letter-spacing: -0.01em;
  color: var(--gray-900);
}

.post-excerpt {
  font-size: 1rem;
  color: var(--gray-500);
  margin: 0 0 16px 0;
  line-height: 1.6;
}

.post-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 16px;
  font-size: 0.85rem;
  color: var(--gray-400);
}

.meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.meta-item svg {
  color: var(--gray-400);
}

.tags {
  display: flex;
  gap: 8px;
}

.tag {
  background: var(--gray-100);
  color: var(--gray-600);
  padding: 2px 10px;
  border-radius: 16px;
  font-size: 0.75rem;
  font-weight: 500;
  transition: background 0.2s ease, color 0.2s ease;
}

.post-item:hover .tag {
  background: var(--bg);
  border-color: var(--gray-200);
}

/* --- Article Detail View --- */
.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--gray-500);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  margin-bottom: 40px;
  transition: color 0.2s ease, transform 0.2s ease;
}

.back-btn:hover {
  color: var(--gray-900);
  transform: translateX(-4px);
}

.article-header {
  margin-bottom: 48px;
}

.article-header h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin: 0 0 16px 0;
  letter-spacing: -0.03em;
  line-height: 1.2;
  color: var(--gray-900);
}

.article-header .post-meta {
  font-size: 0.9rem;
  color: var(--gray-500);
}

/* Markdown Content Styling */
.markdown-body {
  font-size: 1.05rem;
  line-height: 1.7;
  color: var(--gray-800);
}

.markdown-body h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin: 2em 0 1em;
  letter-spacing: -0.02em;
  color: var(--gray-900);
}

.markdown-body h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 1.5em 0 0.75em;
  color: var(--gray-900);
}

.markdown-body p {
  margin-bottom: 1.5em;
}

.markdown-body a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: border-bottom-color 0.2s ease;
}

.markdown-body a:hover {
  border-bottom-color: var(--accent);
}

/* High-contrast Code Blocks */
.markdown-body pre {
  background: #111111;
  border: 1px solid #333333;
  border-radius: 8px;
  padding: 20px;
  overflow-x: auto;
  margin: 2em 0;
}

.markdown-body code {
  font-family: var(--font-mono);
  font-size: 0.85em;
}

.markdown-body p code,
.markdown-body li code {
  background: var(--gray-100);
  color: var(--accent);
  padding: 0.2em 0.4em;
  border-radius: 4px;
}

.markdown-body pre code {
  color: #f5f5f5;
  background: transparent;
  padding: 0;
}

.markdown-body blockquote {
  border-left: 2px solid var(--gray-900);
  margin: 2em 0;
  padding: 4px 0 4px 20px;
  color: var(--gray-600);
  font-style: normal;
  font-size: 1.1rem;
}

.markdown-body img {
  max-width: 100%;
  border-radius: 8px;
  border: 1px solid var(--gray-200);
  margin: 2em 0;
}

.markdown-body ul, 
.markdown-body ol {
  padding-left: 20px;
  margin-bottom: 1.5em;
}

.markdown-body li {
  margin-bottom: 0.5em;
}

/* Minimalist Footer */
.footer {
  margin-top: 80px;
  padding-top: 32px;
  border-top: 1px solid var(--gray-200);
  color: var(--gray-400);
  font-size: 0.85rem;
}