/* ========== CUSTOM PROPERTIES ========== */
:root {
  --bg: #0f0f0f;
  --surface: #1a1a1a;
  --border: #2a2a2a;
  --muted: #666;
  --secondary: #999;
  --primary: #e0e0e0;
  --white: #fff;
  --accent: #60a5fa;
  --accent-hover: #93bbfd;
  --font-display: 'JetBrains Mono', monospace;
  --font-body: 'Source Serif 4', Georgia, serif;
  --font-code: 'JetBrains Mono', monospace;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-body);
  color: var(--secondary);
  background: var(--bg);
  line-height: 1.7;
  padding-top: 56px;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.15s ease;
}

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

/* ========== NAVIGATION ========== */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: var(--bg);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.nav-inner {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.9rem;
  color: var(--white);
  letter-spacing: -0.02em;
}

.nav-title:hover {
  color: var(--white);
}

.nav-links {
  display: flex;
  gap: 24px;
}

.nav-links a {
  font-family: var(--font-display);
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.02em;
  transition: color 0.15s ease;
}

.nav-links a:hover {
  color: var(--primary);
}

/* ========== MAIN ========== */
.site-main {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
  min-height: calc(100vh - 56px - 80px);
}

/* ========== HERO ========== */
.hero {
  padding: 64px 0 48px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 48px;
}

.hero-title {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.4rem);
  font-weight: 700;
  color: var(--white);
  letter-spacing: -0.03em;
  margin-bottom: 8px;
}

.cursor {
  color: var(--accent);
  animation: blink 1s step-end infinite;
}

@keyframes blink {
  50% { opacity: 0; }
}

.hero-tagline {
  font-family: var(--font-display);
  font-size: 0.9rem;
  color: var(--muted);
  letter-spacing: 0.02em;
}

/* ========== POST LIST ========== */
.post-list {
  padding-bottom: 64px;
}

.post-item {
  padding: 32px 0;
  border-bottom: 1px solid var(--border);
  transition: transform 0.15s ease;
}

.post-item:first-child {
  padding-top: 0;
}

.post-item:hover {
  transform: translateX(4px);
}

.post-item-date {
  font-family: var(--font-display);
  font-size: 0.75rem;
  color: var(--muted);
  letter-spacing: 0.04em;
  display: block;
  margin-bottom: 6px;
}

.post-item-title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 8px;
}

.post-item-title a {
  color: var(--primary);
  transition: color 0.15s ease;
}

.post-item-title a:hover {
  color: var(--white);
}

.post-item-excerpt {
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--muted);
}

.post-item-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 12px;
}

.tag {
  font-family: var(--font-display);
  font-size: 0.7rem;
  color: var(--muted);
  border: 1px solid var(--border);
  padding: 2px 8px;
  border-radius: 3px;
  letter-spacing: 0.02em;
}

/* ========== PAGINATION ========== */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  padding: 32px 0;
  font-family: var(--font-display);
  font-size: 0.85rem;
}

.pagination-link {
  color: var(--accent);
}

.pagination-current {
  color: var(--muted);
}

/* ========== SINGLE POST ========== */
.post {
  padding: 48px 0 64px;
}

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

.post-meta {
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 16px;
}

.post-meta time {
  font-family: var(--font-display);
  font-size: 0.8rem;
  color: var(--muted);
  letter-spacing: 0.04em;
}

.post-tags {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.post-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2.2rem);
  font-weight: 700;
  color: var(--white);
  line-height: 1.3;
  letter-spacing: -0.02em;
}

/* ========== POST CONTENT ========== */
.post-content {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--secondary);
}

.post-content h2 {
  font-family: var(--font-display);
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--primary);
  margin: 48px 0 16px;
  letter-spacing: -0.01em;
}

.post-content h3 {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--primary);
  margin: 36px 0 12px;
}

.post-content h4 {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--primary);
  margin: 28px 0 8px;
}

.post-content p {
  margin-bottom: 20px;
}

.post-content a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: rgba(96, 165, 250, 0.3);
  transition: text-decoration-color 0.15s ease;
}

.post-content a:hover {
  text-decoration-color: var(--accent);
}

.post-content strong {
  color: var(--primary);
  font-weight: 600;
}

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

.post-content ul,
.post-content ol {
  margin: 0 0 20px 24px;
}

.post-content li {
  margin-bottom: 6px;
}

.post-content blockquote {
  border-left: 3px solid var(--accent);
  padding: 4px 0 4px 20px;
  margin: 24px 0;
  color: var(--muted);
  font-style: italic;
}

.post-content blockquote p {
  margin-bottom: 0;
}

.post-content img {
  border-radius: 6px;
  margin: 24px 0;
  border: 1px solid var(--border);
}

.post-content table {
  width: 100%;
  border-collapse: collapse;
  margin: 24px 0;
  font-size: 0.9rem;
}

.post-content th,
.post-content td {
  border: 1px solid var(--border);
  padding: 10px 14px;
  text-align: left;
}

.post-content th {
  background: var(--surface);
  color: var(--primary);
  font-family: var(--font-display);
  font-size: 0.8rem;
  font-weight: 700;
}

/* ========== CODE ========== */
.post-content code {
  font-family: var(--font-code);
  font-size: 0.85em;
  background: var(--surface);
  border: 1px solid var(--border);
  padding: 2px 6px;
  border-radius: 3px;
  color: var(--primary);
}

.post-content pre {
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
  padding: 20px 24px;
  margin: 24px 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.post-content pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 0.85rem;
  line-height: 1.6;
  color: inherit;
  border-radius: 0;
}

.highlight pre {
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 6px;
  padding: 20px 24px;
  margin: 24px 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.highlight pre code {
  background: none;
  border: none;
  padding: 0;
  border-radius: 0;
}

/* ========== POST FOOTER ========== */
.post-footer {
  margin-top: 64px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.post-author {
  font-family: var(--font-display);
  font-size: 0.8rem;
  color: var(--muted);
}

.back-link {
  font-family: var(--font-display);
  font-size: 0.8rem;
  color: var(--accent);
}

/* ========== PAGE ========== */
.page {
  padding: 48px 0 64px;
}

.page-title {
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 4vw, 2rem);
  font-weight: 700;
  color: var(--white);
  margin-bottom: 32px;
  letter-spacing: -0.02em;
}

.page-content {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--secondary);
}

.page-content p {
  margin-bottom: 20px;
}

.page-content a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-color: rgba(96, 165, 250, 0.3);
}

.page-content a:hover {
  text-decoration-color: var(--accent);
}

.page-content ul,
.page-content ol {
  margin: 0 0 20px 24px;
}

.page-content li {
  margin-bottom: 6px;
}

.page-content img {
  border-radius: 6px;
  margin: 16px 0;
}

/* ========== FOOTER ========== */
.footer {
  border-top: 1px solid var(--border);
  padding: 24px 0;
}

.footer-inner {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
  font-family: var(--font-display);
  font-size: 0.75rem;
  color: var(--muted);
  display: flex;
  gap: 8px;
}

.footer-sep {
  color: var(--border);
}

/* ========== RESPONSIVE ========== */
@media (max-width: 600px) {
  body {
    padding-top: 48px;
  }

  .nav-inner {
    height: 48px;
    padding: 0 16px;
  }

  .nav-links {
    gap: 16px;
  }

  .site-main {
    padding: 0 16px;
  }

  .hero {
    padding: 40px 0 32px;
    margin-bottom: 32px;
  }

  .post-item {
    padding: 24px 0;
  }

  .post {
    padding: 32px 0 48px;
  }

  .post-content pre {
    padding: 16px;
    margin-left: -16px;
    margin-right: -16px;
    border-radius: 0;
    border-left-width: 3px;
    border-right: none;
  }

  .highlight pre {
    padding: 16px;
    margin-left: -16px;
    margin-right: -16px;
    border-radius: 0;
    border-left-width: 3px;
    border-right: none;
  }

  .footer-inner {
    padding: 0 16px;
  }
}

/* ========== ANIMATIONS ========== */
@media (prefers-reduced-motion: no-preference) {
  .post-item {
    opacity: 0;
    transform: translateY(8px);
    animation: fade-in 0.4s ease forwards;
  }

  .post-item:nth-child(1) { animation-delay: 0s; }
  .post-item:nth-child(2) { animation-delay: 0.05s; }
  .post-item:nth-child(3) { animation-delay: 0.1s; }
  .post-item:nth-child(4) { animation-delay: 0.15s; }
  .post-item:nth-child(5) { animation-delay: 0.2s; }
  .post-item:nth-child(6) { animation-delay: 0.25s; }
  .post-item:nth-child(7) { animation-delay: 0.3s; }
  .post-item:nth-child(8) { animation-delay: 0.35s; }
  .post-item:nth-child(9) { animation-delay: 0.4s; }
  .post-item:nth-child(10) { animation-delay: 0.45s; }
}

@keyframes fade-in {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}