/* privatepanda.co — hand-edited, no build step.
   Palette from the panda photo: green-black night, warm fur-white, moss.
   Moss (--moss) means "interactive / live signal" and nothing else.
   Amber (--amber) means "status / pay attention" and is never a link.
   Sub-pages sit on a faint engineering grid; featured work is drawn as
   blueprint schematics (inline SVG, classes .schematic below). */

:root {
  --bg: #0b0d0b;
  --surface: rgba(233, 231, 223, 0.025);
  --ink: #e9e7df;
  --mut: #99a196;
  --moss: #a3b18a;
  --amber: #d0a568;
  --line: rgba(233, 231, 223, 0.16);
  --hairline: rgba(233, 231, 223, 0.08);
  --mono: ui-monospace, "SF Mono", "Cascadia Code", Consolas, "Liberation Mono", monospace;
  --sans: system-ui, "Segoe UI", "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
[hidden] { display: none !important; }

html { background: var(--bg); scroll-behavior: smooth; }

/* pages with and without a scrollbar must center identically: always reserve the gutter */
html { overflow-y: scroll; }
@supports (scrollbar-gutter: stable) {
  html { overflow-y: auto; scrollbar-gutter: stable; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  font-family: var(--sans);
  color: var(--ink);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

/* engineering-grid backdrop for inner pages */
body.sub {
  background-image:
    radial-gradient(ellipse 90rem 30rem at 50% -6rem, rgba(163, 177, 138, 0.07), transparent),
    linear-gradient(rgba(163, 177, 138, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(163, 177, 138, 0.035) 1px, transparent 1px);
  background-size: auto, 36px 36px, 36px 36px;
}

a { color: var(--moss); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }

/* links inside running text are underlined at rest, so they read as links */
.page p a,
.cdesc a {
  text-decoration: underline;
  text-decoration-color: rgba(163, 177, 138, 0.45);
  text-underline-offset: 3px;
}
.page p a:hover,
.cdesc a:hover { text-decoration-color: var(--moss); }

/* primary action on a card — unmistakably clickable */
.go {
  display: inline-block;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  border: 1px solid rgba(163, 177, 138, 0.55);
  padding: 0.3rem 0.75rem;
  transition: background-color 120ms ease, border-color 120ms ease;
}
.go:hover {
  background: rgba(163, 177, 138, 0.14);
  border-color: var(--moss);
  text-decoration: none;
}
a:focus-visible {
  outline: 2px solid var(--moss);
  outline-offset: 3px;
  border-radius: 2px;
}

::selection { background: var(--moss); color: var(--bg); }

/* ---------- shared type roles ---------- */

.eyebrow {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--mut);
}

.meta {
  font-family: var(--mono);
  font-size: 0.76rem;
  color: var(--mut);
}

/* ---------- inner pages ---------- */

.page {
  max-width: 84rem;
  margin: 0 auto;
  padding: 0 1.5rem 1.25rem;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
}

/* masthead */

.masthead {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  align-items: center;
  gap: 0.7rem;
  padding: 1.1rem 0;
  border-bottom: 1px solid var(--line);
  background: transparent;
  backdrop-filter: blur(10px);
}

.masthead .logo img {
  display: block;
  height: 26px;
  width: auto;
  filter: invert(0.92) sepia(0.06);
}

.masthead .wordmark {
  font-family: var(--mono);
  font-size: 0.82rem;
  letter-spacing: 0.1em;
  color: var(--ink);
}
.masthead .wordmark:hover { color: var(--moss); text-decoration: none; }

.masthead nav {
  margin-left: auto;
  display: flex;
  flex-wrap: wrap;
  gap: 1.3rem;
  font-family: var(--mono);
  font-size: 0.76rem;
  letter-spacing: 0.08em;
}
.masthead nav a { color: var(--mut); }
.masthead nav a:hover { color: var(--moss); text-decoration: none; }
.masthead nav a[aria-current="page"] { color: var(--ink); }

@media (max-width: 40rem) {
  .masthead { flex-wrap: wrap; }
  .masthead nav {
    margin-left: 0;
    flex-basis: 100%;
    padding-top: 0.6rem;
    gap: 1rem;
  }
}

/* page hero */

.hero { padding: 2.2rem 0 1.6rem; }
.hero .meta { display: block; margin-top: 0.55rem; }

/* left sidebar: on-this-page sections + items (scrollspy) */

.layout {
  display: grid;
  grid-template-columns: 12.5rem minmax(0, 1fr);
  gap: 0 2.8rem;
  align-items: start;
  /* the rail lives in the page's empty left margin; content is never shifted */
  margin-left: -15.3rem;
}

.layout > .hero { grid-column: 2; grid-row: 1; }
.layout > .main { grid-column: 2; grid-row: 2; }

.pagenav {
  position: sticky;
  top: 5.2rem;
  max-height: calc(100vh - 6.5rem);
  overflow-y: auto;
  background: transparent;
  grid-column: 1;
  grid-row: 2;
  margin-top: 3.2rem;
  padding: 0.4rem 0 1rem;
  font-family: var(--mono);
  letter-spacing: 0.05em;
}

.pn-group { margin-bottom: 1.3rem; }

.pagenav .pn-sec {
  display: block;
  margin-bottom: 0.4rem;
  font-size: 0.66rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink);
}
.pagenav .pn-sec:hover { color: var(--moss); text-decoration: none; }
.pagenav .pn-sec[aria-current] { color: var(--moss); }

.pagenav a:not(.pn-sec) {
  display: block;
  padding: 0.17rem 0 0.17rem 0.85rem;
  border-left: 1px solid var(--hairline);
  font-size: 0.72rem;
  color: var(--mut);
}
.pagenav a:not(.pn-sec):hover { color: var(--ink); text-decoration: none; }
.pagenav a:not(.pn-sec)[aria-current] { color: var(--moss); border-left-color: var(--moss); }

.page [id] { scroll-margin-top: 5.5rem; }

@media (max-width: 112.5rem) {
  .layout { display: block; margin-left: 0; }
  .pagenav { display: none; }
}
.page .hero + section { margin-top: 1rem; }

.hero h1 {
  font-size: clamp(2rem, 5vw, 2.9rem);
  font-weight: 300;
  letter-spacing: -0.01em;
  margin: 0.3rem 0 0.7rem;
}

.hero .lede { color: var(--mut); max-width: 44em; }

/* sections */

.page section { margin-top: 3.6rem; }

.page h2 {
  display: flex;
  align-items: baseline;
  gap: 0.8rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  font-weight: 400;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink);
  margin-bottom: 1.5rem;
}
.page h2 .n { color: var(--moss); }
.page h2::after { content: ""; flex: 1; border-bottom: 1px solid var(--line); }

.page p { margin-bottom: 1rem; }

/* featured cards */

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(20rem, 1fr));
  gap: 1rem;
}

.fcard {
  border: 1px solid var(--line);
  background: var(--surface);
  padding: 1.3rem 1.4rem 1.2rem;
  transition: border-color 120ms ease;
  display: flex;
  flex-direction: column;
}
.fcard:hover { border-color: rgba(163, 177, 138, 0.55); }
.fcard.wide { grid-column: 1 / -1; }

.fcard h3 { font-size: 1.1rem; font-weight: 500; }
.fcard h3 a, .rcard h3 a { color: var(--ink); }
.fcard h3 a:hover, .rcard h3 a:hover { color: var(--moss); text-decoration: none; }
.fcard .meta { display: block; margin: 0.3rem 0 0.8rem; }
.fcard p { font-size: 0.95rem; margin-bottom: 0.7rem; }
.fcard .tech {
  margin-top: auto;
  padding-top: 0.4rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--mut);
}
.fcard .links { margin-top: 0.6rem; font-family: var(--mono); font-size: 0.78rem; }
.fcard .links a { margin-right: 1.2rem; }

/* blueprint schematics */

.schematic {
  width: 100%;
  height: auto;
  display: block;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--hairline);
  padding-bottom: 0.8rem;
}
.schematic .ln  { stroke: rgba(153, 161, 150, 0.65); fill: none; stroke-width: 1.2; }
.schematic .lnd { stroke: rgba(153, 161, 150, 0.5); fill: none; stroke-width: 1.2; stroke-dasharray: 4 4; }
.schematic .hl  { stroke: var(--moss); fill: none; stroke-width: 1.5; }
.schematic .bx  { fill: rgba(233, 231, 223, 0.03); stroke: rgba(153, 161, 150, 0.65); stroke-width: 1.2; }
.schematic .nd  { fill: var(--moss); stroke: none; }
.schematic .ndm { fill: rgba(153, 161, 150, 0.8); stroke: none; }
.schematic .bar { fill: rgba(153, 161, 150, 0.35); stroke: none; }
.schematic .barh{ fill: rgba(163, 177, 138, 0.55); stroke: none; }
.schematic text { font-family: var(--mono); font-size: 8.5px; letter-spacing: 0.08em; fill: var(--mut); }
.schematic text.hlt { fill: var(--moss); }

.badge {
  font-family: var(--mono);
  font-size: 0.66rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  border: 1px solid var(--line);
  color: var(--mut);
  padding: 0.12rem 0.45rem;
  margin-left: 0.6rem;
  vertical-align: 2px;
  white-space: nowrap;
}
.badge.live { border-color: var(--moss); color: var(--moss); }
.badge.now { border-color: rgba(208, 165, 104, 0.55); color: var(--amber); }

/* research cards */

.rcard {
  border: 1px solid var(--hairline);
  border-left: 2px solid rgba(163, 177, 138, 0.5);
  background: var(--surface);
  padding: 1.1rem 1.3rem;
}
.rcard h3 { font-size: 1.02rem; font-weight: 500; }
.rcard .meta { display: block; margin: 0.25rem 0 0.7rem; }
.rcard p { font-size: 0.93rem; margin-bottom: 0.6rem; }
.rcard .tech { font-family: var(--mono); font-size: 0.72rem; color: var(--mut); }
.rcard .links { margin-top: 0.5rem; font-family: var(--mono); font-size: 0.78rem; }

/* publications */

.pub {
  border: 1px solid var(--hairline);
  border-left: 2px solid var(--moss);
  background: var(--surface);
  padding: 1rem 1.3rem;
  margin-bottom: 0.8rem;
}
.pub .title { font-weight: 500; }
.pub .meta { display: block; margin-top: 0.25rem; }
.pub p { margin: 0.5rem 0 0; color: var(--mut); font-size: 0.92rem; }

/* full paper write-up (publications page — the canonical description) */
.pub.full { padding: 1.3rem 1.5rem 1.2rem; margin-bottom: 1rem; }
.pub.full h3 { font-size: 1.1rem; font-weight: 500; line-height: 1.4; }
.pub.full p { color: var(--ink); font-size: 0.95rem; margin: 0.8rem 0 0; }
.pub.full .tech {
  margin-top: 0.7rem;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--mut);
}
.pub.full .links { margin-top: 0.9rem; font-family: var(--mono); font-size: 0.78rem; }
.pub.full .links a { margin-right: 1rem; }

/* detail pages: one project per page */

.schematic.solo { max-width: 38rem; }
.schematic.solo.wide { max-width: 64rem; }

.dlist { list-style: none; max-width: 62rem; }
.dlist li {
  border-left: 2px solid rgba(163, 177, 138, 0.35);
  padding: 0.05rem 0 0.05rem 1.1rem;
  margin-bottom: 1rem;
  font-size: 0.95rem;
}

/* home: Now + Papers + Explore share one band — the whole page fits one viewport */

.homerow {
  display: grid;
  grid-template-columns: 5fr 4fr 3fr;
  gap: 0 2.2rem;
  align-items: start;
  margin-bottom: 5rem;
}
.homerow section { margin-top: 2.2rem; margin-bottom: 0 !important; }
@media (max-width: 64rem) { .homerow { display: block; } }

/* home directory list */

#now .schematic { max-height: 9rem; }

.dir {
  display: grid;
  grid-template-columns: 1fr;
  gap: 0.5rem;
  list-style: none;
}

.dir a {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  padding: 0.62rem 0.9rem;
  border: 1px solid var(--line);
  color: var(--ink);
  text-decoration: none;
  transition: border-color 120ms ease, background-color 120ms ease;
}

.dir a:hover {
  border-color: var(--moss);
  background: var(--surface);
  text-decoration: none;
}

.dir .name {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.dir .arrow { color: var(--mut); }
.dir a:hover .arrow { color: var(--moss); }

.dir .count {
  margin-left: auto;
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--mut);
  white-space: nowrap;
}

@media (max-width: 64rem) {
  .dir { grid-template-columns: repeat(auto-fill, minmax(18rem, 1fr)); }
}

/* catalogue tiles */

.tiles {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
  gap: 0.7rem;
  list-style: none;
}

.tiles li.arch { opacity: 0.55; }

.archtag {
  font-family: var(--mono);
  font-size: 0.6rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--mut);
  border: 1px solid var(--line);
  padding: 0.05rem 0.35rem;
  margin-left: 0.4rem;
  vertical-align: 1.5px;
}

.tiles li {
  border: 1px solid var(--hairline);
  background: var(--surface);
  padding: 0.75rem 0.9rem 0.7rem;
  transition: border-color 120ms ease;
}
.tiles li:hover { border-color: rgba(163, 177, 138, 0.45); }

.tiles .cname {
  display: block;
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  margin-bottom: 0.3rem;
}
.tiles .cdesc { font-size: 0.85rem; color: var(--mut); line-height: 1.45; }

/* full catalogue */

.cat { list-style: none; }
.cat li {
  display: grid;
  grid-template-columns: 12.5rem 6rem 1fr;
  gap: 1rem;
  align-items: baseline;
  padding: 0.5rem 0;
  border-bottom: 1px solid var(--hairline);
  font-size: 0.9rem;
}
.cat .cname { font-family: var(--mono); font-size: 0.8rem; }
.cat .ctag {
  font-family: var(--mono);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--moss);
}
.cat .cdesc { color: var(--mut); }

@media (max-width: 44rem) {
  .cat li { grid-template-columns: 1fr 6rem; }
  .cat .cdesc { grid-column: 1 / -1; }
}

/* cross-reference line under a section */
.xref { font-family: var(--mono); font-size: 0.78rem; color: var(--mut); margin-top: 0.9rem; }

/* about / contact / footer */

.prose { max-width: 44rem; }

.contact { margin-top: 0.5rem; font-family: var(--mono); font-size: 0.85rem; }
.contact li { list-style: none; padding: 0.3rem 0; }
.contact .k { display: inline-block; width: 6.5rem; color: var(--mut); }

.page section:last-of-type { margin-bottom: 5rem; }

.foot {
  margin-top: auto;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--mut);
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}