/* ============================================================
   CHESSCHAT PORTFOLIO — SHARED STYLES
   Design: Editorial minimalism. Monospace accents on clean sans.
   Palette: Near-black on off-white, amber accent.
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=DM+Sans:ital,opsz,wght@0,9..40,300;0,9..40,400;0,9..40,500;0,9..40,600;1,9..40,300&family=DM+Mono:wght@400;500&display=swap');

/* ── Variables ───────────────────────────────────────────── */
:root {
  --bg:          #f7f6f3;
  --surface:     #ffffff;
  --border:      #e4e2dc;
  --text:        #1a1916;
  --text-muted:  #6b6860;
  --accent:      #c8820a;
  --accent-dim:  #f5e8cf;
  --mono:        'DM Mono', monospace;
  --sans:        'DM Sans', sans-serif;
  --radius:      6px;
  --max-w:       760px;
  --max-w-wide:  1100px;
}

/* ── Reset ───────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ── Typography ──────────────────────────────────────────── */
h1, h2, h3, h4 {
  font-family: var(--sans);
  font-weight: 600;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: var(--text);
}
h1 { font-size: clamp(2rem, 5vw, 3rem); }
h2 { font-size: clamp(1.35rem, 3vw, 1.75rem); margin-top: 2.5rem; margin-bottom: 0.75rem; }
h3 { font-size: 1.15rem; margin-top: 1.75rem; margin-bottom: 0.5rem; }
h4 { font-size: 0.95rem; text-transform: uppercase; letter-spacing: 0.08em; color: var(--text-muted); margin-top: 1.5rem; margin-bottom: 0.4rem; }
p  { margin-bottom: 1rem; color: var(--text); }
p:last-child { margin-bottom: 0; }

ul, ol { padding-left: 1.4rem; margin-bottom: 1rem; }
li { margin-bottom: 0.3rem; }

strong { font-weight: 600; }
em { font-style: italic; }

/* ── Code / Mono ─────────────────────────────────────────── */
code {
  font-family: var(--mono);
  font-size: 0.85em;
  background: var(--accent-dim);
  color: var(--accent);
  padding: 0.15em 0.4em;
  border-radius: 3px;
}

pre {
  font-family: var(--mono);
  font-size: 0.82rem;
  background: #1a1916;
  color: #e8e4dc;
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius);
  overflow-x: auto;
  margin: 1.25rem 0;
  line-height: 1.6;
}
pre code {
  background: none;
  color: inherit;
  padding: 0;
  font-size: inherit;
}

/* ── Layout Containers ───────────────────────────────────── */
.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1.5rem;
}
.container--wide {
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
}

/* ── Site Nav ────────────────────────────────────────────── */
.site-nav {
  border-bottom: 1px solid var(--border);
  background: var(--bg);
  position: sticky;
  top: 0;
  z-index: 100;
}
.site-nav__inner {
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: 54px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.site-nav__logo {
  font-family: var(--mono);
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text);
  text-decoration: none;
  letter-spacing: 0.01em;
}
.site-nav__logo:hover { text-decoration: none; color: var(--accent); }
.site-nav__links {
  display: flex;
  gap: 1.75rem;
  list-style: none;
  padding: 0;
  margin: 0;
}
.site-nav__links a {
  font-size: 0.88rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.15s;
}
.site-nav__links a:hover { color: var(--text); text-decoration: none; }

/* ── Page Header ─────────────────────────────────────────── */
.page-header {
  padding: 4rem 0 3rem;
  border-bottom: 1px solid var(--border);
}
.page-header__eyebrow {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 0.75rem;
}
.page-header__title { margin-bottom: 1rem; }
.page-header__subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  font-weight: 300;
  max-width: 580px;
  line-height: 1.6;
}

/* ── Tag Chips ───────────────────────────────────────────── */
.tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0.75rem 0;
}
.tag {
  font-family: var(--mono);
  font-size: 0.72rem;
  background: var(--accent-dim);
  color: var(--accent);
  padding: 0.2em 0.6em;
  border-radius: 3px;
  letter-spacing: 0.03em;
}
.tag--grey {
  background: #efefed;
  color: var(--text-muted);
}

/* ── Status Badge ────────────────────────────────────────── */
.status {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--mono);
  font-size: 0.75rem;
  padding: 0.25em 0.7em;
  border-radius: 20px;
  font-weight: 500;
}
.status--live   { background: #e6f4ea; color: #2d7a3a; }
.status--wip    { background: #fff4e0; color: #9a6000; }
.status--planned { background: #efefed; color: var(--text-muted); }
.status::before { content: ''; width: 6px; height: 6px; border-radius: 50%; background: currentColor; }

/* ── Cards ───────────────────────────────────────────────── */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: border-color 0.15s, box-shadow 0.15s;
}
.card:hover {
  border-color: #ccc9c0;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}
.card__eyebrow {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
}
.card__title {
  font-size: 1.25rem;
  font-weight: 600;
  margin-bottom: 0.6rem;
  margin-top: 0;
}
.card__desc {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-bottom: 1rem;
  line-height: 1.6;
}
.card__links {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  margin-top: 1.25rem;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
}
.card__links a {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--accent);
}

/* ── Project Grid ────────────────────────────────────────── */
.project-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 1.25rem;
  margin: 2.5rem 0;
}

/* ── Decision Block ──────────────────────────────────────── */
.decision {
  border-left: 3px solid var(--accent);
  padding: 0.75rem 1.25rem;
  background: var(--accent-dim);
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 1.25rem 0;
}
.decision__label {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.3rem;
}
.decision p { margin: 0; font-size: 0.95rem; }

/* ── Callout ─────────────────────────────────────────────── */
.callout {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  background: var(--surface);
  margin: 1.25rem 0;
  font-size: 0.95rem;
}
.callout--warn {
  border-color: #e8c96a;
  background: #fffbee;
}
.callout--info {
  border-color: #a8c8e8;
  background: #f0f7ff;
}

/* ── Schema Cards ────────────────────────────────────────── */
.schema-card {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  margin: 1.25rem 0;
  overflow: hidden;
}
.schema-card__header {
  background: var(--text);
  color: #f7f6f3;
  padding: 0.55rem 1rem;
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
}
.schema-card__section {
  padding: 0.65rem 1rem;
  border-bottom: 1px solid var(--border);
}
.schema-card__section:last-child { border-bottom: none; }
.schema-card__section-label {
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 0.4rem;
  font-weight: 500;
}
.schema-card__row {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  margin-bottom: 0.3rem;
  line-height: 1.4;
}
.schema-card__row:last-child { margin-bottom: 0; }
.schema-badge {
  font-family: var(--mono);
  font-size: 0.68rem;
  font-weight: 500;
  padding: 0.1em 0.45em;
  border-radius: 3px;
  flex-shrink: 0;
}
.schema-badge--pk  { background: var(--accent-dim); color: var(--accent); border: 1px solid #e0b878; }
.schema-badge--sk  { background: #e8f0f8; color: #3a6ea0; border: 1px solid #b8d0e8; }
.schema-badge--gsi { background: #f0eeeb; color: var(--text-muted); border: 1px solid var(--border); }
.schema-card__key      { font-family: var(--mono); font-size: 0.82rem; color: var(--text); }
.schema-card__key-note { font-size: 0.8rem; color: var(--text-muted); }
.schema-card__attrs    { font-family: var(--mono); font-size: 0.78rem; color: var(--text); line-height: 1.7; }
.schema-card__attrs .ref { color: var(--accent); }
.schema-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin: 1.25rem 0;
}
@media (max-width: 580px) { .schema-grid { grid-template-columns: 1fr; } }

/* ── Table ───────────────────────────────────────────────── */
.table-wrap { overflow-x: auto; margin: 1.25rem 0; }
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}
th {
  text-align: left;
  font-weight: 600;
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  padding: 0.6rem 1rem;
  border-bottom: 2px solid var(--border);
}
td {
  padding: 0.65rem 1rem;
  border-bottom: 1px solid var(--border);
  vertical-align: top;
}
tr:last-child td { border-bottom: none; }
td code { font-size: 0.8rem; }

/* ── Diagram Placeholder ─────────────────────────────────── */
.diagram-placeholder {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 3rem 2rem;
  text-align: center;
  color: var(--text-muted);
  background: var(--surface);
  margin: 1.5rem 0;
}
.diagram-placeholder__label {
  font-family: var(--mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.5rem;
  color: var(--accent);
}
.diagram-placeholder p { font-size: 0.88rem; margin: 0; }

/* ── Page Layout with Sidebar ────────────────────────────── */
.page-layout {
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 3rem;
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 3rem 1.5rem;
  align-items: start;
}
.page-sidebar {
  position: sticky;
  top: 72px;
}
.page-sidebar__title {
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}
.page-sidebar nav { display: flex; flex-direction: column; gap: 0.1rem; }
.page-sidebar nav a {
  font-size: 0.85rem;
  color: var(--text-muted);
  text-decoration: none;
  padding: 0.3rem 0.6rem;
  border-radius: 4px;
  transition: background 0.12s, color 0.12s;
  border-left: 2px solid transparent;
}
.page-sidebar nav a:hover {
  color: var(--text);
  background: var(--accent-dim);
  text-decoration: none;
}
.page-sidebar nav a.active {
  color: var(--accent);
  border-left-color: var(--accent);
  background: var(--accent-dim);
}
.page-sidebar nav .nav-section {
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  padding: 0.75rem 0.6rem 0.2rem;
  opacity: 0.6;
}
.page-content { min-width: 0; }
.page-content section { padding-top: 2.5rem; margin-bottom: 0.5rem; }
.page-content section:first-child { padding-top: 0; }
.section-divider {
  border: none;
  border-top: 1px solid var(--border);
  margin: 2.5rem 0;
}

/* ── Footer ──────────────────────────────────────────────── */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0;
  margin-top: 5rem;
}
.site-footer__inner {
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 1rem;
}
.site-footer p {
  font-size: 0.82rem;
  color: var(--text-muted);
  margin: 0;
}
.site-footer__links {
  display: flex;
  gap: 1.5rem;
  list-style: none;
  padding: 0;
  margin: 0;
}
.site-footer__links a {
  font-size: 0.82rem;
  color: var(--text-muted);
}
.site-footer__links a:hover { color: var(--text); }

/* ── Hero (landing page) ─────────────────────────────────── */
.hero {
  padding: 6rem 0 4rem;
}
.hero__mono {
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--accent);
  letter-spacing: 0.08em;
  margin-bottom: 1rem;
}
.hero__name {
  font-size: clamp(2.5rem, 6vw, 4rem);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.1;
  margin-bottom: 1.25rem;
}
.hero__bio {
  font-size: 1.1rem;
  color: var(--text-muted);
  font-weight: 300;
  max-width: 520px;
  line-height: 1.7;
  margin-bottom: 2rem;
}
.hero__links {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.88rem;
  font-weight: 500;
  padding: 0.55em 1.1em;
  border-radius: var(--radius);
  text-decoration: none;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
  border: 1px solid transparent;
}
.btn--primary {
  background: var(--text);
  color: var(--bg);
}
.btn--primary:hover { background: #333; text-decoration: none; color: var(--bg); }
.btn--outline {
  border-color: var(--border);
  color: var(--text);
  background: transparent;
}
.btn--outline:hover { border-color: #aaa; text-decoration: none; }

/* ── Section headings on landing ────────────────────────────*/
.section-label {
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border);
}

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 768px) {
  .page-layout {
    grid-template-columns: 1fr;
    padding: 2rem 1rem;
  }
  .page-sidebar {
    position: static;
    border-bottom: 1px solid var(--border);
    padding-bottom: 1.5rem;
    margin-bottom: 0.5rem;
  }
  .page-sidebar nav { flex-direction: row; flex-wrap: wrap; }
  .site-nav__links { gap: 1rem; }
  .project-grid { grid-template-columns: 1fr; }
  .hero { padding: 3.5rem 0 2.5rem; }
  .site-footer__inner { flex-direction: column; align-items: flex-start; }
}

/* ── Scroll-activated sidebar highlight ─────────────────── */
/* JS handles .active class on sidebar links */