:root {
  --fg: #1a1a1a;
  --muted: #666;
  --accent: #0b5cff;
  --bg: #ffffff;
  --line: #e6e6e6;
  --chip-bg: #f1f3f7;
  --chip-bg-hover: #dfe4ec;
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; background: var(--bg); color: var(--fg); }

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
               "Helvetica Neue", Arial, sans-serif;
  line-height: 1.6;
  font-size: 16px;
}

main, header, footer {
  max-width: 860px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  padding-top: 1.25rem;
  padding-bottom: 1rem;
  margin-bottom: 2rem;
}
header .brand a { color: var(--fg); font-weight: 600; text-decoration: none; font-size: 1.1rem; }
header nav a { color: var(--muted); text-decoration: none; margin-left: 1rem; font-size: 0.92rem; }
header nav a:hover { color: var(--fg); }

footer {
  border-top: 1px solid var(--line);
  margin-top: 4rem;
  padding: 1.25rem 1.5rem 2rem;
  color: var(--muted);
  font-size: 0.85rem;
}
footer a { color: var(--muted); }

h1, h2, h3, h4 { line-height: 1.25; margin-top: 1.6em; }
h1 { font-size: 2rem; margin-top: 0; }
h2 { font-size: 1.4rem; }
h3 { font-size: 1.15rem; }

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

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 0.92em;
  background: var(--chip-bg);
  padding: 0.1em 0.35em;
  border-radius: 3px;
}
pre { background: #f7f8fa; padding: 1rem; overflow-x: auto; border-radius: 6px; }
pre code { background: transparent; padding: 0; }

table { border-collapse: collapse; margin: 1rem 0; }
th, td { padding: 0.4rem 0.8rem; border-bottom: 1px solid var(--line); text-align: left; }

blockquote {
  border-left: 3px solid var(--line);
  margin: 1rem 0;
  padding: 0.2rem 1rem;
  color: var(--muted);
}

/* Project tree */
ul.tree { list-style: none; padding-left: 1.25rem; margin: 0.5rem 0 1rem; }
ul.tree ul.tree { border-left: 1px dashed var(--line); margin-left: 0.4rem; }
ul.tree li { margin: 0.35rem 0; }
ul.tree .icon { display: inline-block; width: 1.4em; }
ul.tree .project > a { font-weight: 600; color: var(--fg); }
ul.tree .project .desc { color: var(--muted); font-size: 0.88rem; margin-left: 1.4em; }

.actions { display: inline-block; margin-left: 0.5rem; }
.actions a {
  font-size: 0.75rem;
  background: var(--chip-bg);
  padding: 0.08rem 0.5rem;
  border-radius: 3px;
  color: var(--muted);
  margin-right: 0.25rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}
.actions a:hover { background: var(--chip-bg-hover); color: var(--fg); text-decoration: none; }

/* Paper */
.paper-meta { color: var(--muted); font-size: 0.92rem; margin-bottom: 1.5rem; }
.abstract { background: #fafbfd; border-left: 3px solid var(--accent); padding: 0.8rem 1rem; margin: 1.5rem 0 2rem; }
.paper-actions { margin: 0 0 1.5rem; font-size: 0.9rem; }
.paper-actions a { color: var(--muted); }
.paper-body { font-size: 1.02rem; }

/* Home intro */
.home > p:first-of-type { font-size: 1.08rem; color: var(--muted); }