/* ── Variables ── */
:root {
  --bg:         #111213;
  --bg-nav:     #16181a;
  --bg-card:    #1a1c1f;
  --border:     #2a2d31;
  --text:       #d6d8da;
  --text-muted: #6b7280;
  --text-dim:   #8f97a1;
  --accent:     #7eb8b8;
  --accent-dim: rgba(126, 184, 184, 0.12);
  --code-bg:    #1e2124;
  --font-sans:  'DM Sans', sans-serif;
  --font-mono:  'DM Mono', monospace;
  --font-serif: 'DM Serif Display', serif;
  --max-w:      680px;
  --nav-h:      52px;
}

[data-theme="light"] {
  --bg:         #f7f6f2;
  --bg-nav:     #eeecea;
  --bg-card:    #eae8e3;
  --border:     #d4d0c8;
  --text:       #1a1c1f;
  --text-muted: #5a6070;
  --text-dim:   #7a8494;
  --code-bg:    #e2e0da;
  --accent-dim: rgba(126, 184, 184, 0.15);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    --bg: #f7f6f2; --bg-nav: #eeecea; --bg-card: #eae8e3;
    --border: #d4d0c8; --text: #1a1c1f; --text-muted: #5a6070;
    --text-dim: #7a8494; --code-bg: #e2e0da;
    --accent-dim: rgba(126, 184, 184, 0.15);
  }
}

/* ── Reset ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 300;
  line-height: 1.7;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ── Skip link ── */
.skip-link {
  position: absolute; top: -40px; left: 0;
  background: var(--accent); color: var(--bg);
  padding: 0.4rem 0.8rem; font-size: 0.8rem;
  border-radius: 0 0 4px 0; text-decoration: none; transition: top 0.15s;
}
.skip-link:focus { top: 0; }

/* ── Nav ── */
#site-nav {
  position: sticky; top: 0; z-index: 100;
  background: var(--bg-nav);
  border-bottom: 1px solid var(--border);
  height: var(--nav-h);
}

#site-nav nav {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 100%;
  display: flex;
  align-items: center;
}

#site-nav nav ul {
  display: flex; align-items: center;
  list-style: none; width: 100%;
}

#site-nav nav ul li a,
#site-nav nav ul li button {
  display: inline-flex; align-items: center;
  padding: 0.3rem 0.65rem; border-radius: 6px;
  font-size: 0.875rem; font-family: var(--font-mono);
  color: var(--text-dim); text-decoration: none;
  background: none; border: none; cursor: pointer;
  transition: color 0.15s, background 0.15s; white-space: nowrap;
}

#site-nav nav ul li a:hover,
#site-nav nav ul li button:hover { color: var(--text); background: var(--accent-dim); }

#site-nav nav ul li a.active { color: var(--accent); background: var(--accent-dim); }
#site-nav nav ul li#home a { font-weight: 500; color: var(--text); margin-right: 0.25rem; }

.nav-divider { width: 1px; height: 18px; background: var(--border); margin: 0 0.5rem; flex-shrink: 0; }
.nav-spacer { flex: 1; }

/* ── Main ── */
main {
  flex: 1;
  max-width: var(--max-w);
  width: 100%;
  margin: 0 auto;
  padding: 3.5rem 1.5rem 4rem;
}

/* ── Homepage ── */
h1 {
  font-family: var(--font-serif);
  font-size: 2.4rem; font-weight: 400;
  letter-spacing: -0.01em; color: var(--text);
  margin-bottom: 0.75rem; line-height: 1.2;
}

blockquote {
  border-left: 3px solid var(--accent);
  padding-left: 1rem; color: var(--text-dim);
  font-size: 0.975rem; font-style: italic; margin-bottom: 3rem;
}
blockquote p { margin: 0; }

.section-entry { margin-bottom: 2.25rem; }
.section-entry h2 { font-family: var(--font-serif); font-size: 1.35rem; font-weight: 400; color: var(--text); margin-bottom: 0.3rem; }
.section-entry p { font-size: 0.925rem; color: var(--text-dim); line-height: 1.65; }
.section-entry a { color: var(--accent); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 3px; transition: opacity 0.15s; }
.section-entry a:hover { opacity: 0.75; }

/* ── Page headers (projects, about) ── */
.page-h1 { font-family: var(--font-serif); font-size: 2.4rem; font-weight: 400; letter-spacing: -0.01em; margin-bottom: 0.5rem; }
.page-desc { color: var(--text-dim); font-size: 0.925rem; margin-bottom: 2.5rem; }
.page-count { font-size: 0.8rem; font-family: var(--font-mono); color: var(--text-muted); margin-bottom: 1.5rem; }

/* ── Project cards ── */
.project-list { display: flex; flex-direction: column; gap: 0.75rem; }

.project-card {
  position: relative; padding: 1.25rem 1.5rem; border-radius: 8px;
  background: var(--bg-card); border: 1px solid var(--border); transition: border-color 0.15s;
}
.project-card:hover { border-color: var(--accent); }
.project-card a.card-link { position: absolute; inset: 0; border-radius: 8px; }
.project-card h3 { font-family: var(--font-mono); font-size: 0.95rem; font-weight: 500; color: var(--accent); margin-bottom: 0.35rem; }
.project-card p { font-size: 0.9rem; color: var(--text-dim); line-height: 1.6; }
.tags { display: flex; flex-wrap: wrap; gap: 0.4rem; margin-top: 0.75rem; }
.tag { font-size: 0.72rem; font-family: var(--font-mono); color: var(--text-muted); background: var(--bg); border: 1px solid var(--border); padding: 0.15rem 0.5rem; border-radius: 4px; }
.project-card .details { margin-top: 0.6rem; font-size: 0.78rem; font-family: var(--font-mono); color: var(--text-muted); }

/* ── Project detail page ── */
.project-article { max-width: var(--max-w); }

.project-header { margin-bottom: 2.5rem; }
.back-link {
  display: inline-flex; align-items: center; gap: 0.35rem;
  font-size: 0.8rem; font-family: var(--font-mono); color: var(--text-muted);
  text-decoration: none; margin-bottom: 1.5rem; transition: color 0.15s;
}
.back-link:hover { color: var(--accent); }
.back-link::before { content: '←'; }

.project-header h1 { font-family: var(--font-serif); font-size: 2.1rem; font-weight: 400; margin-bottom: 0.75rem; line-height: 1.25; }

.project-meta {
  display: flex; align-items: center; flex-wrap: wrap; gap: 0.75rem;
  font-size: 0.78rem; font-family: var(--font-mono); color: var(--text-muted);
  margin-bottom: 1rem;
}

.status-badge {
  display: inline-flex; align-items: center; gap: 0.3rem;
  padding: 0.2rem 0.6rem; border-radius: 20px;
  font-size: 0.72rem; font-family: var(--font-mono); font-weight: 500;
  border: 1px solid;
}
.status-live { color: #6db87a; border-color: rgba(109,184,122,0.35); background: rgba(109,184,122,0.08); }
.status-live::before { content: ''; display: inline-block; width: 6px; height: 6px; border-radius: 50%; background: #6db87a; }
.status-wip { color: #c4a84e; border-color: rgba(196,168,78,0.35); background: rgba(196,168,78,0.08); }
.status-wip::before { content: ''; display: inline-block; width: 6px; height: 6px; border-radius: 50%; background: #c4a84e; }

.project-header .tags { margin-top: 0; }

.github-link {
  display: inline-flex; align-items: center; gap: 0.4rem;
  font-size: 0.82rem; font-family: var(--font-mono);
  color: var(--accent); text-decoration: none; border: 1px solid var(--accent);
  padding: 0.35rem 0.85rem; border-radius: 6px; margin-top: 1.25rem;
  transition: background 0.15s; opacity: 0.85;
}
.github-link:hover { background: var(--accent-dim); opacity: 1; }
.github-link svg { width: 15px; height: 15px; fill: currentColor; }

/* ── Article body ── */
.article-body { margin-top: 2.5rem; border-top: 1px solid var(--border); padding-top: 2.5rem; }

.article-body h2 {
  font-family: var(--font-serif); font-size: 1.4rem; font-weight: 400;
  color: var(--text); margin: 2rem 0 0.6rem;
}
.article-body h2:first-child { margin-top: 0; }

.article-body h3 {
  font-family: var(--font-mono); font-size: 0.9rem; font-weight: 500;
  color: var(--text-dim); margin: 1.5rem 0 0.5rem; letter-spacing: 0.02em;
  text-transform: uppercase;
}

.article-body p { font-size: 0.95rem; color: var(--text-dim); margin-bottom: 1rem; line-height: 1.75; }
.article-body p:last-child { margin-bottom: 0; }

.article-body a { color: var(--accent); text-decoration: underline; text-underline-offset: 3px; text-decoration-thickness: 1px; }
.article-body a:hover { opacity: 0.75; }

.article-body strong { color: var(--text); font-weight: 500; }
.article-body em { font-style: italic; }

.article-body code {
  font-family: var(--font-mono); font-size: 0.82em;
  background: var(--code-bg); color: var(--accent);
  padding: 0.1em 0.4em; border-radius: 4px; border: 1px solid var(--border);
}

.article-body pre {
  background: var(--code-bg); border: 1px solid var(--border);
  border-radius: 8px; padding: 1.25rem 1.5rem; overflow-x: auto;
  margin: 1.25rem 0;
}
.article-body pre code {
  background: none; border: none; padding: 0;
  font-size: 0.85rem; color: var(--text-dim);
}

.article-body ul, .article-body ol {
  padding-left: 1.5rem; margin-bottom: 1rem; color: var(--text-dim); font-size: 0.95rem;
}
.article-body li { margin-bottom: 0.3rem; line-height: 1.7; }

/* Callout / note box */
.callout {
  border-left: 3px solid var(--accent); background: var(--accent-dim);
  padding: 1rem 1.25rem; border-radius: 0 8px 8px 0; margin: 1.5rem 0;
}
.callout p { color: var(--text-dim); font-size: 0.9rem; margin: 0; }
.callout strong { color: var(--text); }

/* Architecture diagram placeholder */
.arch-block {
  background: var(--code-bg); border: 1px solid var(--border);
  border-radius: 8px; padding: 1.25rem 1.5rem; margin: 1.25rem 0;
  font-family: var(--font-mono); font-size: 0.82rem; color: var(--text-dim);
  white-space: pre; overflow-x: auto; line-height: 1.6;
}

/* ── Footer ── */
footer { border-top: 1px solid var(--border); padding: 1.5rem; }
footer ul { list-style: none; display: flex; justify-content: center; gap: 1.25rem; }
footer a { display: inline-flex; align-items: center; gap: 0.4rem; color: var(--text-muted); text-decoration: none; font-family: var(--font-mono); font-size: 0.8rem; transition: color 0.15s; }
footer a:hover { color: var(--accent); }
footer svg { width: 18px; height: 18px; fill: currentColor; }

/* ── Utilities ── */
.external::after { content: '↗'; font-size: 0.75em; margin-left: 0.15em; opacity: 0.6; }

@media (max-width: 600px) {
  h1, .page-h1, .project-header h1 { font-size: 1.9rem; }
  main { padding: 2.5rem 1.25rem 3rem; }
}