/* ==========================================================================
   Decentralized Safe Path Following for Multiple Quadrotors
   Project page. Palette is taken from the simulation plots themselves, so the
   page and the figures read as one document.
   ========================================================================== */

:root{
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  --accent-2:#3D7AB0;
  --accent-soft:#E9F0F7;
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  --warn:#9C5A0B;
  --warn-soft:#FBEEDD;
  --bad:#B32B36;
  --bad-soft:#FBE9EA;
  --fig-plate:#FFFFFF;
  --fig-filter:none;
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  --shadow-2:0 1px 2px rgba(14,20,24,.05), 0 14px 34px -20px rgba(14,20,24,.30);
  --rail:212px;
  --measure:70ch;
}

@media (prefers-color-scheme: dark){
  :root:not([data-theme="light"]){
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:root[data-theme="dark"]{
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}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:5.5rem}
@media (prefers-reduced-motion: reduce){html{scroll-behavior:auto}}

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h2{font-size:clamp(1.6rem,2.5vw,2.05rem);line-height:1.18;letter-spacing:-.01em}
h3{font-size:1.16rem;line-height:1.3;font-weight:600}
p{margin:0 0 1.05em}
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a:hover{border-bottom-color:var(--accent)}
a:focus-visible,button:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:3px}
code,kbd{font-family:"IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,monospace;font-size:.88em}
strong{font-weight:600}

/* ---------- shell ---------------------------------------------------- */

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.topbar nav{display:flex;gap:1.15rem;font-size:.86rem}
.topbar nav a{color:var(--ink-2);border:0}
.topbar nav a:hover{color:var(--accent)}
@media (max-width:900px){.topbar nav{display:none}}

.shell{
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  padding:0 clamp(1rem,3.4vw,2.4rem) 6rem;
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}
@media (min-width:1180px){
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}

.rail{display:none}
@media (min-width:1180px){
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main{min-width:0}
section{scroll-margin-top:5.4rem}
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/* ---------- hero ------------------------------------------------------ */

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.btn.primary:hover{color:#fff;filter:brightness(1.08)}
.btn svg{width:15px;height:15px}

/* ---------- section furniture ----------------------------------------- */

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.sec:last-of-type{border-bottom:0}
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.sec-head p{margin:0;color:var(--ink-2);max-width:var(--measure)}
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.prose p.tight{margin-bottom:.5em}

/* ---------- figure plates --------------------------------------------- */

.plate{
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}
.plate img,.plate video{display:block;width:100%;height:auto;border-radius:8px;filter:var(--fig-filter)}
figure{margin:0}
figure + figcaption,.cap{
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}
.cap b{color:var(--ink-2);font-weight:600}
.figblock{margin:0 0 1.6rem}

.grid2{display:grid;grid-template-columns:1fr;gap:1.5rem}
.grid3{display:grid;grid-template-columns:1fr;gap:1.5rem}
@media (min-width:760px){.grid2{grid-template-columns:1fr 1fr}}
@media (min-width:980px){.grid3{grid-template-columns:repeat(3,1fr)}}

.card{
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/* a video card is mostly video: the plate frame would only steal width from it */
.card .plate{padding:0;border:0;box-shadow:none;border-radius:10px}
.card.media{padding:.85rem .85rem 1rem}
.card.media h3{font-size:1.05rem}

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}
.pill.ok{background:var(--ok-soft);color:var(--ok)}
.pill.bad{background:var(--bad-soft);color:var(--bad)}
.pill.warn{background:var(--warn-soft);color:var(--warn)}
.pill.neutral{background:var(--surface-2);color:var(--muted)}

/* ---------- key numbers ------------------------------------------------ */

.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(168px,1fr));gap:1px;
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/* ---------- tables ----------------------------------------------------- */

.tablewrap{overflow-x:auto;border:1px solid var(--rule);border-radius:14px;background:var(--surface)}
table{border-collapse:collapse;width:100%;font-size:.9rem;min-width:520px}
th,td{padding:.62rem .95rem;text-align:left;border-bottom:1px solid var(--rule)}
thead th{
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  color:var(--muted);font-weight:500;background:var(--surface-2);white-space:nowrap;
}
tbody tr:last-child td{border-bottom:0}
td.num,th.num{text-align:right;font-family:"IBM Plex Mono",monospace;font-variant-numeric:tabular-nums}
td.best{color:var(--ok);font-weight:600}

/* ---------- code ------------------------------------------------------- */

pre{
  margin:0 0 1.1rem;background:var(--surface-2);border:1px solid var(--rule);border-radius:12px;
  padding:.95rem 1.1rem;overflow-x:auto;font-size:.85rem;line-height:1.62;color:var(--ink-2);
}
pre code{font-family:"IBM Plex Mono",monospace}
pre .c{color:var(--muted)}

/* ---------- lists ------------------------------------------------------ */

ul.look{list-style:none;margin:.2rem 0 0;padding:0;display:grid;gap:.55rem;max-width:var(--measure)}
ul.look li{position:relative;padding-left:1.5rem;color:var(--ink-2);font-size:.955rem}
ul.look li::before{
  content:"";position:absolute;left:.28rem;top:.62em;width:.44rem;height:.44rem;border-radius:50%;
  background:var(--accent);
}

/* ---------- footer ----------------------------------------------------- */

footer{padding:2.6rem 0 0;color:var(--muted);font-size:.88rem}
footer .rulebar{height:1px;background:var(--rule);margin-bottom:1.6rem}

/* ---------- motion ----------------------------------------------------- */

.reveal{opacity:0;transform:translateY(10px);transition:opacity .55s ease,transform .55s ease}
.reveal.in{opacity:1;transform:none}
@media (prefers-reduced-motion: reduce){.reveal{opacity:1;transform:none;transition:none}}