/* ─── Tokens ─────────────────────────────────────────── */
:root {
  color-scheme: light;
  --bg: #f7f5ef;
  --surface: #fffdf8;
  --surface-strong: #ffffff;
  --text: #171717;
  --muted: #66645e;
  --line: #e5dfd3;
  --accent: #202020;
  --accent-soft: #ebe5d8;
  --shadow: 0 24px 70px rgba(20, 20, 20, 0.08);
  --shadow-sm: 0 8px 28px rgba(20, 20, 20, 0.06);
  --radius-sm: 12px;
  --radius: 18px;
  --radius-lg: 28px;
  --transition: 200ms ease;
  --max: 1120px;
  --font-mono: "JetBrains Mono", ui-monospace, "Fira Code", Consolas, monospace;
}

html[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0d0f10;
  --surface: #151719;
  --surface-strong: #1b1e21;
  --text: #f3f1ea;
  --muted: #b8b3a8;
  --line: #2b2f33;
  --accent: #f3f1ea;
  --accent-soft: #25282c;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.38);
  --shadow-sm: 0 8px 28px rgba(0, 0, 0, 0.22);
}

/* ─── Reset & Base ───────────────────────────────────── */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background:
    radial-gradient(circle at top left, color-mix(in srgb, var(--accent-soft) 70%, transparent), transparent 34rem),
    var(--bg);
  color: var(--text);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.65;
}

a { color: inherit; text-decoration: none; }
a:hover { opacity: .78; }
img { max-width: 100%; display: block; }

/* ─── Skip link ──────────────────────────────────────── */
.skip-link {
  position: absolute;
  left: -999px;
  top: 1rem;
  background: var(--surface-strong);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: .6rem 1rem;
}
.skip-link:focus { left: 1rem; z-index: 100; }

/* ─── Header ─────────────────────────────────────────── */
.header {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: .95rem clamp(1rem, 4vw, 3rem);
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.brand {
  font-weight: 800;
  letter-spacing: -.045em;
  font-size: 1.08rem;
}

.nav, .actions, .language-links, .button-row {
  display: flex;
  align-items: center;
  gap: .75rem;
  flex-wrap: wrap;
}

.nav a, .language-links a {
  color: var(--muted);
  font-size: .95rem;
}

.nav a[aria-current="page"], .language-links a[aria-current="true"] {
  color: var(--text);
  font-weight: 700;
}

/* ─── Mobile menu toggle ─────────────────────────────── */
.menu-toggle {
  display: none;
  background: var(--surface-strong);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: .45rem .65rem;
  cursor: pointer;
  color: var(--text);
  font-size: 1.15rem;
  line-height: 1;
  align-items: center;
  justify-content: center;
}
.menu-toggle:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ─── Buttons ────────────────────────────────────────── */
.theme-toggle, .button {
  border: 1px solid var(--line);
  background: var(--surface-strong);
  color: var(--text);
  border-radius: 999px;
  padding: .62rem .9rem;
  box-shadow: none;
  cursor: pointer;
  font: inherit;
  transition: opacity var(--transition), background var(--transition), border-color var(--transition);
}
.theme-toggle:focus-visible, .button:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.button.primary {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}

.button.secondary { background: transparent; }
.button:hover { opacity: .82; }

/* ─── Layout ─────────────────────────────────────────── */
.main { width: min(var(--max), calc(100% - 2rem)); margin: 0 auto; }

/* ─── Hero ───────────────────────────────────────────── */
.hero {
  display: flex;
  align-items: center;
  padding: clamp(4rem, 10vw, 7rem) 0 clamp(3rem, 7vw, 5rem);
  min-height: 78vh;
}

.hero-inner {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: clamp(2.5rem, 6vw, 5rem);
  align-items: center;
  width: 100%;
}

.hero-photo-col {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.1rem;
}

.hero-text-col { text-align: left; }
.hero-text-col h1 { text-align: left; }
.hero-text-col .lead { margin-left: 0; }

.profile-photo {
  width: 190px;
  height: 190px;
  border-radius: 50%;
  object-fit: cover;
  object-position: center;
  border: 5px solid var(--surface-strong);
  box-shadow: 0 18px 45px rgba(0, 0, 0, .16);
  flex-shrink: 0;
}

/* ─── Typography ─────────────────────────────────────── */
h1, h2, h3 { line-height: 1.1; letter-spacing: -.05em; }
h1 { font-size: clamp(2.2rem, 6.5vw, 4.8rem); margin: 0 0 1rem; }
h2 { font-size: clamp(1.7rem, 4vw, 2.8rem); margin: 0 0 1rem; }
h3 { font-size: 1.15rem; margin: 0 0 .55rem; }

.kicker {
  display: inline-flex;
  gap: .45rem;
  align-items: center;
  margin: 0 0 1.1rem;
  padding: .38rem .85rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  background: var(--accent-soft);
  font-size: .88rem;
}

.lead {
  max-width: 760px;
  margin: 0 auto 1.5rem;
  color: var(--muted);
  font-size: clamp(1.05rem, 2vw, 1.22rem);
}

/* ─── Sections ───────────────────────────────────────── */
.section { padding: clamp(2.5rem, 7vw, 5rem) 0; }
.section-header { max-width: 760px; margin-bottom: 2rem; }
.section-header p { color: var(--muted); }

/* ─── Grid ───────────────────────────────────────────── */
.grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 1rem; }
.grid.two { grid-template-columns: repeat(2, minmax(0, 1fr)); }

/* ─── Cards ──────────────────────────────────────────── */
.card, .article-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.4rem;
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
}
.card:hover, a.article-card:hover {
  box-shadow: var(--shadow);
  transform: translateY(-2px);
  border-color: var(--muted);
  opacity: 1;
}
.card p, .article-card p { color: var(--muted); }

/* ─── Card enhancements (projects) ──────────────────── */
.card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: .5rem;
  margin-bottom: .45rem;
}
.card-status {
  font-size: .72rem;
  text-transform: uppercase;
  letter-spacing: .07em;
  font-family: var(--font-mono);
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: .22rem .6rem;
  white-space: nowrap;
  flex-shrink: 0;
}
.card-links { display: flex; gap: .5rem; margin-top: 1rem; flex-wrap: wrap; }
.card-link {
  font-size: .84rem;
  padding: .35rem .8rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--text);
  transition: background var(--transition), border-color var(--transition);
  display: inline-flex;
  align-items: center;
  gap: .3rem;
}
.card-link:hover { background: var(--accent-soft); border-color: var(--muted); opacity: 1; }

/* ─── Tags ───────────────────────────────────────────── */
.tags { display: flex; flex-wrap: wrap; gap: .45rem; margin-top: 1rem; }
.tag {
  font-size: .8rem;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: .22rem .55rem;
}

/* ─── Skills section ─────────────────────────────────── */
.skills-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1rem;
}

.skill-category {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1.25rem;
  background: var(--surface);
  box-shadow: var(--shadow-sm);
}

.skill-category h3 {
  font-size: .76rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--muted);
  margin: 0 0 .8rem;
  font-weight: 600;
}

.skill-pills { display: flex; flex-wrap: wrap; gap: .4rem; }

.skill-pill {
  font-size: .8rem;
  font-family: var(--font-mono);
  background: var(--accent-soft);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: .25rem .65rem;
  color: var(--text);
}

/* ─── Timeline ───────────────────────────────────────── */
.timeline { display: grid; gap: 0; list-style: none; margin: 0; padding: 0; }

.timeline-item {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 1.5rem;
  padding: 1.75rem 0;
  border-bottom: 1px solid var(--line);
}
.timeline-item:last-child { border-bottom: none; }

.timeline-date {
  font-size: .85rem;
  color: var(--muted);
  font-family: var(--font-mono);
  padding-top: .22rem;
  line-height: 1.4;
}

.timeline-body h3 { margin: 0 0 .25rem; font-size: 1.08rem; }
.timeline-body .timeline-org {
  font-size: .88rem;
  color: var(--muted);
  margin: 0 0 .65rem;
}
.timeline-body p { color: var(--muted); margin: 0 0 .75rem; font-size: .95rem; }

/* ─── Blog index ─────────────────────────────────────── */
.tag-filter {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  margin-bottom: 1.75rem;
}

.tag-filter-btn {
  font-size: .84rem;
  padding: .32rem .8rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font: inherit;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.tag-filter-btn:hover { background: var(--accent-soft); border-color: var(--muted); color: var(--text); }
.tag-filter-btn[aria-pressed="true"] {
  background: var(--accent);
  color: var(--bg);
  border-color: var(--accent);
}
.tag-filter-btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.article-list { display: grid; gap: 1rem; }

.article-card {
  display: grid;
  gap: .5rem;
  text-decoration: none;
}

.article-card-meta {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  align-items: center;
  font-size: .82rem;
  color: var(--muted);
}
.article-card-meta .tag { margin: 0; }
.article-card h3 { margin: 0; font-size: 1.1rem; }
.reading-time { font-size: .8rem; color: var(--muted); font-family: var(--font-mono); }

/* ─── Page hero ──────────────────────────────────────── */
.page-hero { padding: clamp(3rem, 8vw, 6rem) 0 2rem; max-width: 860px; }
.page-text { max-width: 820px; }

/* ─── Breadcrumb ─────────────────────────────────────── */
.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: .3rem;
  align-items: center;
  font-size: .85rem;
  color: var(--muted);
  margin-bottom: 2rem;
}
.breadcrumb a { color: var(--muted); text-decoration: underline; text-underline-offset: 3px; }
.breadcrumb a:hover { opacity: .75; }
.breadcrumb-sep { opacity: .4; }

/* ─── Article ────────────────────────────────────────── */
.article-header {
  max-width: 820px;
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
  border-bottom: 1px solid var(--line);
}

.article-author {
  display: flex;
  align-items: center;
  gap: .8rem;
  margin-top: 1.5rem;
}

.article-author img {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  object-fit: cover;
  flex-shrink: 0;
}

.article-author-info { font-size: .88rem; }
.article-author-info strong { display: block; }
.article-author-info span { color: var(--muted); }

.article-meta { color: var(--muted); font-size: .92rem; }

.article-content { max-width: 840px; padding-bottom: 5rem; }
.article-content p { color: var(--text); line-height: 1.8; }
.article-content h2 { margin-top: 2.5rem; font-size: clamp(1.4rem, 3vw, 2rem); }
.article-content h3 { margin-top: 1.75rem; }

.article-content code {
  font-family: var(--font-mono);
  font-size: .88em;
  background: var(--accent-soft);
  padding: .15em .4em;
  border-radius: 4px;
}

.article-content pre {
  background: var(--surface-strong);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 1.25rem;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: .9rem;
  line-height: 1.6;
  margin: 1.5rem 0;
}
.article-content pre code { background: none; padding: 0; font-size: inherit; }

/* ─── Contact section ────────────────────────────────── */
.contact-grid {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
  margin-top: 1.5rem;
}

.contact-link {
  display: inline-flex;
  align-items: center;
  gap: .6rem;
  padding: .75rem 1.2rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  font-size: .9rem;
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition), box-shadow var(--transition), transform var(--transition);
}
.contact-link:hover { border-color: var(--muted); box-shadow: var(--shadow); transform: translateY(-1px); opacity: 1; }
.contact-link:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.contact-icon { font-size: 1rem; flex-shrink: 0; }

/* ─── Footer ─────────────────────────────────────────── */
.footer {
  width: min(var(--max), calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0 3rem;
  border-top: 1px solid var(--line);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.footer p { color: var(--muted); font-size: .9rem; margin: 0; }

/* ─── Responsive ─────────────────────────────────────── */
@media (max-width: 820px) {
  /* Header */
  .header { flex-wrap: wrap; align-items: center; gap: .6rem; }
  .menu-toggle { display: flex; }

  /* Collapsible nav */
  .nav {
    display: none;
    flex-direction: column;
    align-items: flex-start;
    width: 100%;
    padding: .75rem 0 .25rem;
    border-top: 1px solid var(--line);
    gap: .4rem;
    order: 10;
  }
  .nav.open { display: flex; }
  .nav a { font-size: 1rem; padding: .2rem 0; }

  /* Hero */
  .hero { min-height: auto; padding: clamp(2.5rem, 8vw, 4rem) 0; }
  .hero-inner { grid-template-columns: 1fr; text-align: center; gap: 1.5rem; }
  .hero-text-col { text-align: center; }
  .hero-text-col h1 { text-align: center; }
  .hero-text-col .lead { margin: 0 auto 1.5rem; }
  .profile-photo { width: 152px; height: 152px; margin: 0 auto; }
  .button-row { justify-content: center; }

  /* Grids */
  .grid, .grid.two { grid-template-columns: 1fr; }

  /* Timeline */
  .timeline-item { grid-template-columns: 1fr; gap: .5rem; }
  .timeline-date { font-size: .82rem; }
}

/* ─── Article figure (SVG diagrams) ─────────────────── */
.article-figure {
  margin: 2.25rem 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--surface);
}
.article-figure svg {
  width: 100%;
  height: auto;
  display: block;
  padding: 1.5rem;
}
.article-figure figcaption {
  padding: .7rem 1.25rem;
  border-top: 1px solid var(--line);
  font-size: .84rem;
  color: var(--muted);
  font-style: italic;
}

/* ─── Article ordered steps ─────────────────────────── */
.article-content ol {
  padding-left: 1.4rem;
  display: grid;
  gap: .75rem;
  color: var(--text);
}
.article-content ol li { line-height: 1.7; }
.article-content ol li strong { color: var(--text); }
.article-content ul {
  padding-left: 1.4rem;
  display: grid;
  gap: .5rem;
  color: var(--muted);
}
.article-content a {
  color: var(--text);
  text-decoration: underline;
  text-underline-offset: 3px;
}
.article-content a:hover { opacity: .72; }

/* ─── Observability charts ───────────────────────────── */
.obs-stat-grid    { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; margin: 1.5rem 0; }
.obs-stat         { background: var(--surface); border: 1px solid var(--line);
                    border-radius: var(--radius-sm); padding: 1.25rem; text-align: center; }
.obs-stat-value   { font-size: 2rem; font-weight: 700; color: var(--text); display: block; }
.obs-stat-label   { font-size: .8rem; color: var(--muted); margin-top: .25rem; display: block; }
.obs-bar-chart    { display: flex; align-items: flex-end; gap: .35rem; height: 80px; margin: 1rem 0; }
.obs-bar          { flex: 1; background: var(--accent-soft); border-radius: 4px 4px 0 0;
                    transition: height .3s ease; min-height: 3px; }
.obs-bar:hover    { background: var(--accent); opacity: .75; }
.obs-bar-label    { font-size: .65rem; color: var(--muted); text-align: center; flex: 1; }
.obs-page-row     { display: flex; align-items: center; gap: .75rem; padding: .5rem 0;
                    border-bottom: 1px solid var(--line); }
.obs-page-bar     { height: 6px; background: var(--accent-soft); border-radius: 3px; flex-shrink: 0; }
.obs-page-name    { font-size: .88rem; color: var(--text); min-width: 0; flex: 1;
                    overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.obs-page-count   { font-size: .8rem; color: var(--muted); font-family: var(--font-mono); }
.obs-status       { display: inline-flex; align-items: center; gap: .4rem; font-size: .8rem;
                    color: var(--muted); font-family: var(--font-mono); margin-left: .75rem; }
.obs-status-dot   { width: 8px; height: 8px; border-radius: 50%; background: var(--muted); flex-shrink: 0; }
.obs-status-dot.ok { background: #4caf50; }
@media (max-width: 600px) { .obs-stat-grid { grid-template-columns: repeat(2, 1fr); } }