/* Big Data Systems Research Group — UH
   Reuses the OPTINET workshop design system. No external fonts, no frameworks. */

:root {
  --ink:        #14151a;
  --muted:      #5b606b;
  --paper:      #ffffff;
  --subtle:     #f5f6f8;
  --line:       #e4e6ec;
  --accent:     #3538cd;
  --accent-ink: #23258f;
  --accent-soft:#eef0ff;
  --sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scrollbar-gutter: stable; }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--ink);
  background: var(--paper);
  line-height: 1.55;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}
main.content { flex: 1; }

.container { max-width: 1000px; margin: 0 auto; padding: 0 24px; }

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

/* ---------- Sticky top nav ---------- */
.wsnav {
  position: sticky; top: 0; z-index: 50;
  background: #0c2f4d;
  border-bottom: 1px solid rgba(255,255,255,0.12);
}
.wsnav-inner {
  display: flex; align-items: center; gap: 22px;
  padding: 9px 0; flex-wrap: wrap;
}
.wsnav-brand { font-weight: 800; font-size: 1.05rem; color: #fff; white-space: nowrap; }
.wsnav-brand:hover { text-decoration: none; }
.wsnav-links { display: flex; gap: 28px; flex-wrap: wrap; }
.wsnav-links a { color: rgba(255,255,255,0.85); font-size: 0.92rem; font-weight: 500; }
.wsnav-links a:hover { color: #fff; text-decoration: none; }
.wsnav-links a[aria-current="page"] { color: #fff; font-weight: 700; }

/* ---------- Banner ---------- */
.wshero {
  position: relative;
  background: linear-gradient(180deg, #12456e 0%, #0c2f4d 100%);
  color: #fff;
  overflow: hidden;
}
.wshero::before {
  content: "";
  position: absolute; inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20viewBox%3D%220%200%201200%20300%22%20preserveAspectRatio%3D%22none%22%3E%3Cline%20x1%3D%2280%22%20y1%3D%2255%22%20x2%3D%22300%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%2255%22%20x2%3D%22300%22%20y2%3D%22118%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%2255%22%20x2%3D%22300%22%20y2%3D%22182%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%2255%22%20x2%3D%22300%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22150%22%20x2%3D%22300%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22150%22%20x2%3D%22300%22%20y2%3D%22118%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22150%22%20x2%3D%22300%22%20y2%3D%22182%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22150%22%20x2%3D%22300%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22245%22%20x2%3D%22300%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22245%22%20x2%3D%22300%22%20y2%3D%22118%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22245%22%20x2%3D%22300%22%20y2%3D%22182%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%2280%22%20y1%3D%22245%22%20x2%3D%22300%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%2255%22%20x2%3D%22520%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%2255%22%20x2%3D%22520%22%20y2%3D%22118%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%2255%22%20x2%3D%22520%22%20y2%3D%22182%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%2255%22%20x2%3D%22520%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22118%22%20x2%3D%22520%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22118%22%20x2%3D%22520%22%20y2%3D%22118%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22118%22%20x2%3D%22520%22%20y2%3D%22182%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22118%22%20x2%3D%22520%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22182%22%20x2%3D%22520%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22182%22%20x2%3D%22520%22%20y2%3D%22118%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22182%22%20x2%3D%22520%22%20y2%3D%22182%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22182%22%20x2%3D%22520%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22245%22%20x2%3D%22520%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22245%22%20x2%3D%22520%22%20y2%3D%22118%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22245%22%20x2%3D%22520%22%20y2%3D%22182%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22300%22%20y1%3D%22245%22%20x2%3D%22520%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%2255%22%20x2%3D%22740%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%2255%22%20x2%3D%22740%22%20y2%3D%22150%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%2255%22%20x2%3D%22740%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22118%22%20x2%3D%22740%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22118%22%20x2%3D%22740%22%20y2%3D%22150%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22118%22%20x2%3D%22740%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22182%22%20x2%3D%22740%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22182%22%20x2%3D%22740%22%20y2%3D%22150%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22182%22%20x2%3D%22740%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22245%22%20x2%3D%22740%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22245%22%20x2%3D%22740%22%20y2%3D%22150%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22520%22%20y1%3D%22245%22%20x2%3D%22740%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22740%22%20y1%3D%2255%22%20x2%3D%22960%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22740%22%20y1%3D%2255%22%20x2%3D%22960%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22740%22%20y1%3D%22150%22%20x2%3D%22960%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22740%22%20y1%3D%22150%22%20x2%3D%22960%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22740%22%20y1%3D%22245%22%20x2%3D%22960%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22740%22%20y1%3D%22245%22%20x2%3D%22960%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22960%22%20y1%3D%2255%22%20x2%3D%221140%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22960%22%20y1%3D%2255%22%20x2%3D%221140%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22960%22%20y1%3D%22245%22%20x2%3D%221140%22%20y2%3D%2255%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Cline%20x1%3D%22960%22%20y1%3D%22245%22%20x2%3D%221140%22%20y2%3D%22245%22%20stroke%3D%22%23bcd8f0%22%20stroke-width%3D%221%22%2F%3E%3Ccircle%20cx%3D%22300%22%20cy%3D%2255%22%20r%3D%2214%22%20fill%3D%22%238fc0e8%22%20opacity%3D%22.16%22%2F%3E%3Ccircle%20cx%3D%22520%22%20cy%3D%22245%22%20r%3D%2214%22%20fill%3D%22%238fc0e8%22%20opacity%3D%22.16%22%2F%3E%3Ccircle%20cx%3D%22740%22%20cy%3D%22150%22%20r%3D%2214%22%20fill%3D%22%238fc0e8%22%20opacity%3D%22.16%22%2F%3E%3Ccircle%20cx%3D%2280%22%20cy%3D%22245%22%20r%3D%2214%22%20fill%3D%22%238fc0e8%22%20opacity%3D%22.16%22%2F%3E%3Ccircle%20cx%3D%2280%22%20cy%3D%2255%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%2280%22%20cy%3D%22150%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%2280%22%20cy%3D%22245%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22300%22%20cy%3D%2255%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22300%22%20cy%3D%22118%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22300%22%20cy%3D%22182%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22300%22%20cy%3D%22245%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22520%22%20cy%3D%2255%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22520%22%20cy%3D%22118%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22520%22%20cy%3D%22182%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22520%22%20cy%3D%22245%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22740%22%20cy%3D%2255%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22740%22%20cy%3D%22150%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22740%22%20cy%3D%22245%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22960%22%20cy%3D%2255%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%22960%22%20cy%3D%22245%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%221140%22%20cy%3D%2255%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3Ccircle%20cx%3D%221140%22%20cy%3D%22245%22%20r%3D%224%22%20fill%3D%22%23dcecfb%22%2F%3E%3C%2Fsvg%3E");
  background-size: 100% 100%;
  opacity: 0.45;
  pointer-events: none;
}
.wshero-title { position: relative; text-align: center; padding: 26px 16px 30px; }
.wshero-title .eyebrow-top {
  font-size: 0.9rem; font-weight: 600; letter-spacing: 0.08em;
  text-transform: uppercase; color: #bfe0ff; margin-bottom: 6px;
}
.wshero-title .main { font-size: clamp(1.5rem, 4vw, 2.4rem); font-weight: 800; margin: 0; }
.wshero-title .sub  { color: #bfe0ff; margin-top: 8px; font-size: clamp(1rem, 2vw, 1.2rem); font-weight: 600; }
.wshero-title .sub a { color: inherit; }

/* ---------- Page title + eyebrow ---------- */
.page-title { padding: 16px 0 0; }
.page-title h1 { font-size: clamp(1.6rem, 3.5vw, 2rem); letter-spacing: -0.02em; margin: 4px 0 0; font-weight: 800; }
.eyebrow {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--accent-ink);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0;
}
.eyebrow::before { content: ""; width: 22px; height: 2px; background: var(--accent); display: inline-block; }

/* ---------- Sections ---------- */
main.content { padding: 2px 0 12px; }
.section { padding: 14px 0; border-bottom: 1px solid var(--line); }
.section:last-child { border-bottom: 0; }
.section h2 { font-size: 1.3rem; letter-spacing: -0.01em; margin: 4px 0 0; font-weight: 700; }
.section > p { margin: 8px 0 0; }
.section > p.sub { color: var(--muted); }
main.content .section:first-of-type { padding-top: 6px; }

/* ---------- Simple lists ---------- */
ul.list { list-style: none; padding: 0; margin: 10px 0 0; }
ul.list li { position: relative; padding: 4px 0 4px 22px; }
ul.list li::before {
  content: ""; position: absolute; left: 3px; top: 11px;
  width: 7px; height: 7px; border: 1.5px solid var(--accent); border-radius: 2px;
}

/* ---------- People ---------- */
.people-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 22px 18px;
  margin-top: 14px;
}
.person { text-align: center; }
.avatar {
  width: 92px; height: 92px; border-radius: 50%;
  margin: 0 auto 10px; display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 1.6rem; color: #fff;
  background: linear-gradient(135deg, #3538cd, #12456e);
  object-fit: cover; overflow: hidden;
}
img.avatar { display: block; }
.person-name { font-weight: 600; line-height: 1.2; }
.person-name a { color: var(--ink); }
.person-role { color: var(--muted); font-size: 0.85rem; margin-top: 2px; }

/* Professor: a single highlighted card */
.lead-person { display: flex; align-items: center; gap: 18px; margin-top: 12px; flex-wrap: wrap; }
.lead-person .avatar { margin: 0; width: 104px; height: 104px; }
.lead-text .person-name { font-size: 1.15rem; }

/* ---------- Research projects ---------- */
.project { padding: 14px 0; border-bottom: 1px solid var(--line); }
.project:last-child { border-bottom: 0; }
.project h3 { margin: 0; font-size: 1.08rem; }
.project .who { font-family: var(--mono); font-size: 0.82rem; color: var(--accent-ink); margin: 3px 0 6px; }
.project p { margin: 0; color: var(--ink); }

/* ---------- Contact / director card ---------- */
.card { background: var(--subtle); border: 1px solid var(--line); border-radius: 12px; padding: 16px 18px; margin-top: 12px; }
.card p { margin: 2px 0; }

.pill {
  display: inline-block; font-family: var(--mono); font-size: 0.72rem;
  background: var(--paper); border: 1px solid var(--line); border-radius: 999px;
  padding: 3px 10px; color: var(--muted);
}

/* ---------- Footer ---------- */
.site-footer { border-top: 1px solid var(--line); background: var(--subtle); padding: 16px 0 22px; margin-top: 8px; }
.site-footer p { margin: 3px 0; font-size: 0.9rem; }
.site-footer .muted { color: var(--muted); }

/* ---------- A11y + responsive ---------- */
a:focus-visible { outline: 3px solid var(--accent); outline-offset: 2px; border-radius: 4px; }
@media (prefers-reduced-motion: reduce) { * { animation: none !important; transition: none !important; } }
@media (max-width: 640px) {
  .wsnav-inner { justify-content: center; text-align: center; gap: 8px 16px; }
  .wsnav-brand { flex-basis: 100%; }
  .wsnav-links { justify-content: center; }
}