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

:root {
  /* Cool slate palette — no warm tones */
  --c-bg: #f8fafc;
  --c-text: #0f172a;
  --c-text-muted: #64748b;
  --c-accent: #0891b2;
  --c-accent-hover: #0e7490;
  --c-border: #e2e8f0;
  --c-surface: #ffffff;
  --c-code-bg: #f1f5f9;

  /* Topic colors */
  --topic-energy: #0d9488;
  --topic-smart-home: #2563eb;
  --topic-urban-transport: #475569;
  --topic-gardening: #16a34a;
  --topic-default: #0891b2;

  /* Tag accent colors — warm allowed here */
  --tag-1: #0d9488;
  --tag-2: #2563eb;
  --tag-3: #475569;
  --tag-4: #16a34a;
  --tag-5: #d97706;
  --tag-6: #dc2626;
  --tag-7: #7c3aed;
  --tag-8: #0891b2;
  --tag-9: #be185d;
  --tag-10: #ca8a04;

  /* Typography */
  --font-sans: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'IBM Plex Mono', 'JetBrains Mono', 'Fira Code', monospace;
  --max-width: 720px;
  --date-col: 7rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --c-bg: #0f172a;
    --c-text: #e2e8f0;
    --c-text-muted: #94a3b8;
    --c-accent: #22d3ee;
    --c-accent-hover: #67e8f9;
    --c-border: #1e293b;
    --c-surface: #1e293b;
    --c-code-bg: #1e293b;

    /* Topic colors — brighter for dark bg */
    --topic-energy: #2dd4bf;
    --topic-smart-home: #60a5fa;
    --topic-urban-transport: #94a3b8;
    --topic-gardening: #4ade80;
    --topic-default: #22d3ee;

    /* Tag colors — adjusted for dark */
    --tag-1: #2dd4bf;
    --tag-2: #60a5fa;
    --tag-3: #94a3b8;
    --tag-4: #4ade80;
    --tag-5: #fbbf24;
    --tag-6: #f87171;
    --tag-7: #a78bfa;
    --tag-8: #22d3ee;
    --tag-9: #f472b6;
    --tag-10: #facc15;
  }
}

html { font-size: 17px; line-height: 1.7; }
body {
  font-family: var(--font-sans);
  color: var(--c-text);
  background: var(--c-bg);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.container { max-width: var(--max-width); margin: 0 auto; padding: 0 1.5rem; width: 100%; }

a { color: var(--c-accent); text-decoration: none; }
a:hover { color: var(--c-accent-hover); text-decoration: underline; }

/* ===== Header ===== */
.site-header {
  border-bottom: 1px solid var(--c-border);
  padding: 1rem 0;
}
.site-header .container { display: flex; align-items: center; justify-content: space-between; }
.site-title {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--c-text);
  letter-spacing: -0.02em;
  font-family: var(--font-mono);
}
.site-title:hover { color: var(--c-accent); text-decoration: none; }
.site-nav { display: flex; gap: 1.5rem; }
.site-nav a {
  color: var(--c-text-muted);
  font-size: 0.9rem;
  font-weight: 500;
}
.site-nav a:hover, .site-nav a.active { color: var(--c-text); text-decoration: none; }

/* ===== Main content ===== */
main { flex: 1; padding: 2rem 0; }

/* ===== Hero (homepage) ===== */
.hero { margin-bottom: 3rem; }
.hero h1 {
  font-size: 2.2rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  line-height: 1.15;
}
.hero-sub { color: var(--c-text-muted); font-size: 1.05rem; margin-top: 0.5rem; }

/* ===== Section headers ===== */
.recent-posts, .topics-overview { margin-bottom: 3rem; }
.recent-posts h2, .topics-overview h2 {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--c-text-muted);
  font-weight: 600;
  margin-bottom: 1.25rem;
}

/* ===== Post previews — date column + colored left border ===== */
.post-preview {
  display: grid;
  grid-template-columns: var(--date-col) 1fr;
  gap: 0 1rem;
  padding: 1rem 0 1rem 0.75rem;
  border-bottom: 1px solid var(--c-border);
  border-left: 3px solid var(--topic-default);
}
.post-preview:first-of-type { border-top: 1px solid var(--c-border); }

/* Topic-specific border colors */
.post-preview[data-topic="energy"] { border-left-color: var(--topic-energy); }
.post-preview[data-topic="smart home"] { border-left-color: var(--topic-smart-home); }
.post-preview[data-topic="smart-home"] { border-left-color: var(--topic-smart-home); }
.post-preview[data-topic="urban transport"] { border-left-color: var(--topic-urban-transport); }
.post-preview[data-topic="urban-transport"] { border-left-color: var(--topic-urban-transport); }
.post-preview[data-topic="gardening"] { border-left-color: var(--topic-gardening); }

.post-preview time {
  font-size: 0.8rem;
  color: var(--c-text-muted);
  font-family: var(--font-mono);
  grid-row: 1;
  padding-top: 0.15rem;
}
.post-preview h3 {
  font-size: 1.15rem;
  font-weight: 600;
  grid-column: 2;
  grid-row: 1;
  line-height: 1.3;
}
.post-preview h3 a { color: var(--c-text); }
.post-preview h3 a:hover { color: var(--c-accent); text-decoration: none; }
.post-preview p {
  color: var(--c-text-muted);
  font-size: 0.9rem;
  line-height: 1.6;
  grid-column: 2;
}
.post-preview .post-topics {
  grid-column: 2;
}

/* ===== Topic badges ===== */
.post-topics { margin-top: 0.4rem; display: flex; gap: 0.4rem; flex-wrap: wrap; }
.topic-badge {
  font-size: 0.7rem;
  font-weight: 600;
  padding: 0.15rem 0.55rem;
  border-radius: 3px;
  background: var(--c-accent);
  color: var(--c-bg);
  text-transform: lowercase;
  letter-spacing: 0.02em;
}
.topic-badge:hover { opacity: 0.85; text-decoration: none; color: var(--c-bg); }

/* Topic-specific badge colors */
.topic-badge[data-topic="energy"] { background: var(--topic-energy); }
.topic-badge[data-topic="smart home"],
.topic-badge[data-topic="smart-home"] { background: var(--topic-smart-home); }
.topic-badge[data-topic="urban transport"],
.topic-badge[data-topic="urban-transport"] { background: var(--topic-urban-transport); }
.topic-badge[data-topic="gardening"] { background: var(--topic-gardening); }

/* ===== Topic grid — tinted backgrounds ===== */
.topic-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 1rem; }
.topic-card {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
  padding: 1.25rem;
  border: 1px solid var(--c-border);
  border-radius: 6px;
  background: var(--c-surface);
  color: var(--c-text);
  transition: border-color 0.15s, background 0.15s;
  border-left: 3px solid var(--topic-default);
}
.topic-card:hover { border-color: var(--c-accent); text-decoration: none; }
.topic-card strong { font-size: 1rem; font-weight: 600; }
.topic-card span { font-size: 0.8rem; color: var(--c-text-muted); font-family: var(--font-mono); }

/* Topic-tinted cards */
.topic-card[data-topic="energy"] {
  border-left-color: var(--topic-energy);
  background: color-mix(in srgb, var(--topic-energy) 5%, var(--c-surface));
}
.topic-card[data-topic="smart home"],
.topic-card[data-topic="smart-home"] {
  border-left-color: var(--topic-smart-home);
  background: color-mix(in srgb, var(--topic-smart-home) 5%, var(--c-surface));
}
.topic-card[data-topic="urban transport"],
.topic-card[data-topic="urban-transport"] {
  border-left-color: var(--topic-urban-transport);
  background: color-mix(in srgb, var(--topic-urban-transport) 5%, var(--c-surface));
}
.topic-card[data-topic="gardening"] {
  border-left-color: var(--topic-gardening);
  background: color-mix(in srgb, var(--topic-gardening) 5%, var(--c-surface));
}

/* ===== Single post ===== */
.post-header { margin-bottom: 2rem; }
.post-header h1 {
  font-size: 1.85rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.2;
}
.post-meta {
  margin-top: 0.75rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  font-size: 0.8rem;
  color: var(--c-text-muted);
}
.post-meta time {
  font-family: var(--font-mono);
}
.reading-time {
  font-family: var(--font-mono);
}
.post-meta .post-topics { margin-top: 0; }

/* ===== Post content ===== */
.post-content { max-width: 65ch; }
.post-content h2 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2.5rem 0 0.75rem;
  letter-spacing: -0.01em;
}
.post-content h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1.75rem 0 0.5rem;
}
.post-content p { margin-bottom: 1rem; }
.post-content ul, .post-content ol { margin: 0 0 1rem 1.5rem; }
.post-content li { margin-bottom: 0.3rem; }
.post-content blockquote {
  border-left: 3px solid var(--c-accent);
  padding-left: 1rem;
  margin: 1.5rem 0;
  color: var(--c-text-muted);
  font-style: italic;
}
.post-content img { max-width: 100%; height: auto; border-radius: 4px; margin: 1.5rem 0; }

/* Tables */
table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-size: 0.9rem;
}
th, td {
  padding: 0.5rem 0.75rem;
  text-align: left;
  border: 1px solid var(--c-border);
}
th {
  font-weight: 600;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  color: var(--c-text-muted);
  background: var(--c-code-bg);
}
tr:nth-child(even) td {
  background: color-mix(in srgb, var(--c-code-bg) 50%, transparent);
}

/* Inline code */
.post-content code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--c-code-bg);
  padding: 0.15em 0.35em;
  border-radius: 3px;
}

/* Code blocks — with language label bar */
.post-content pre {
  background: var(--c-code-bg);
  border-radius: 4px;
  border: 1px solid var(--c-border);
  padding: 1rem;
  overflow-x: auto;
  margin: 1.5rem 0;
  position: relative;
}
.post-content pre code {
  background: none;
  padding: 0;
  font-size: 0.82rem;
  line-height: 1.6;
}

/* ===== Tech stack badges (projects) ===== */
.tech-stack { display: flex; gap: 0.4rem; flex-wrap: wrap; margin-top: 0.5rem; }
.tech-badge {
  font-size: 0.7rem;
  font-weight: 500;
  font-family: var(--font-mono);
  padding: 0.15rem 0.5rem;
  border-radius: 3px;
  border: 1px solid var(--c-border);
  color: var(--c-text-muted);
  background: var(--c-bg);
}

/* ===== Project status ===== */
.project-status {
  font-size: 0.7rem;
  font-weight: 600;
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: 0.15rem 0.5rem;
  border-radius: 3px;
}
.project-status--completed { color: var(--c-text-muted); background: var(--c-code-bg); }
.project-status--in-progress { color: var(--c-bg); background: var(--c-accent); }
.project-status--ongoing { color: var(--topic-energy); border: 1px solid var(--topic-energy); }

/* ===== Project catalog ===== */
.project-catalog { display: grid; grid-template-columns: 1fr; gap: 1rem; }
.project-card {
  padding: 1.25rem;
  border: 1px solid var(--c-border);
  border-left: 3px solid var(--topic-default);
  border-radius: 4px;
  background: var(--c-surface);
  transition: border-color 0.15s;
}
.project-card:hover { border-left-color: var(--c-accent); }
.project-card h3 { font-size: 1.1rem; font-weight: 600; margin-bottom: 0.3rem; }
.project-card h3 a { color: var(--c-text); }
.project-card h3 a:hover { color: var(--c-accent); text-decoration: none; }
.project-card > p {
  font-size: 0.9rem;
  color: var(--c-text-muted);
  line-height: 1.5;
}

@media (min-width: 600px) {
  .project-catalog { grid-template-columns: repeat(2, 1fr); }
}

/* ===== Post tags ===== */
.post-tags {
  margin-top: 2rem;
  padding-top: 1rem;
  border-top: 1px solid var(--c-border);
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}
.post-tags a {
  font-size: 0.8rem;
  color: var(--c-text-muted);
  font-family: var(--font-mono);
}
.post-tags a:hover { color: var(--c-accent); }

/* ===== Section intro ===== */
.section-intro { margin-bottom: 2rem; color: var(--c-text-muted); font-size: 0.95rem; }

/* ===== 404 ===== */
.page-404 {
  text-align: center;
  padding: 4rem 0;
}
.page-404 h1 {
  font-size: 4rem;
  font-weight: 700;
  font-family: var(--font-mono);
  color: var(--c-text-muted);
  letter-spacing: -0.03em;
}
.page-404 p {
  color: var(--c-text-muted);
  margin-top: 0.75rem;
  font-size: 0.95rem;
}
.page-404 a { font-weight: 500; }

/* ===== Footer ===== */
.site-footer {
  border-top: 1px solid var(--c-border);
  padding: 1.5rem 0;
  margin-top: auto;
}
.site-footer p { font-size: 0.8rem; color: var(--c-text-muted); }

/* ===== Responsive ===== */
@media (max-width: 600px) {
  html { font-size: 16px; }
  .hero h1 { font-size: 1.7rem; }
  .post-header h1 { font-size: 1.4rem; }
  .site-header .container { flex-direction: column; gap: 0.75rem; }

  /* Collapse date column on mobile */
  .post-preview {
    display: block;
    padding-left: 0.75rem;
  }
  .post-preview h3 { margin: 0.2rem 0 0.3rem; }
}