/* =========================================================
   main.css — stable layout, big text, banners, collapsibles
   ========================================================= */

:root{
  /* Light theme */
  --bg: #ffffff;
  --text: #111827;
  --muted: #6b7280;
  --accent: #1f2a5a;

  --border: #e5e7eb;

  --nav-text: rgba(255,255,255,.95);
  --nav-text-hover: #ffffff;
  --navbtn-bg: rgba(255,255,255,.14);
  --navbtn-border: rgba(255,255,255,.25);

  --nav-panel: rgba(15,23,42,.88);
  --nav-panel-border: rgba(255,255,255,.18);

  /* Bigger global typography */
  --base-size: 16.5px;
  --line: 1.75;

  /* Layout */
  --maxw: 1040px;
  --navh: 64px;

  --focus: 0 0 0 3px rgba(31,42,90,.25);
}

html.dark{
  --bg: #0b1220;
  --text: #e5e7eb;
  --muted: #a7b0bf;
  --accent: #93a4ff;

  --border: rgba(148,163,184,.22);

  --nav-text: rgba(255,255,255,.92);
  --nav-text-hover: #ffffff;

  --navbtn-bg: rgba(255,255,255,.16);
  --navbtn-border: rgba(255,255,255,.22);

  --nav-panel: rgba(2,6,23,.90);
  --nav-panel-border: rgba(148,163,184,.22);

  --focus: 0 0 0 3px rgba(147,164,255,.25);
}

*{ box-sizing: border-box; }
html{ scroll-behavior: smooth; }
body{
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  font-size: var(--base-size);
  line-height: var(--line);
  color: var(--text);
  background: var(--bg);
}

a{ color: inherit; }
a:hover{ text-decoration: underline; }

:focus-visible{
  outline: none;
  box-shadow: var(--focus);
  border-radius: 10px;
}

.container{
  width: min(var(--maxw), calc(100% - 48px));
  margin: 0 auto;
}

/* ===== Banner / Masthead ===== */
.masthead{
  position: relative;
  height: 360px;                 /* bigger banner */
  background-image: var(--banner, none);
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

/* overlay for text readability on banner */
.masthead::after{
  content:"";
  position:absolute; inset:0;
  background: linear-gradient(to bottom, rgba(0,0,0,.35), rgba(0,0,0,.18), rgba(0,0,0,.05));
}

.topnav{
  position:absolute;
  left:0; right:0; top:0;
  height: var(--navh);
  display:flex;
  align-items:center;
  z-index:2;
}

.topnav-inner{
  width: min(1200px, calc(100% - 48px));
  margin: 0 auto;
  display:flex;
  align-items:center;
  justify-content: space-between;
  gap: 16px;
}

.brand{
  color: var(--nav-text-hover);
  text-decoration:none;
  font-weight: 700;
  letter-spacing: .2px;
}

.navlinks{
  display:flex;
  align-items:center;
  gap: 18px;
}

.navlinks a{
  color: var(--nav-text);
  text-decoration:none;
  font-size: 13px;
  font-weight: 650;
  opacity: .96;
}

.navlinks a:hover{
  color: var(--nav-text-hover);
  opacity: 1;
  text-decoration: underline;
}

.navbtn{
  display:none;
  background: var(--navbtn-bg);
  border: 1px solid var(--navbtn-border);
  color: var(--nav-text-hover);
  padding: 8px 10px;
  border-radius: 10px;
  cursor: pointer;
}

.themebtn{
  background: var(--navbtn-bg);
  border: 1px solid var(--navbtn-border);
  color: var(--nav-text-hover);
  padding: 8px 10px;
  border-radius: 10px;
  cursor: pointer;
  font-size: 14px;
  line-height: 1;
}

.banner-caption{
  position:absolute;
  right: 90px;                   /* center-right */
  top: 50%;
  transform: translateY(-50%);
  z-index:2;
  color: var(--nav-text-hover);
  font-size: 13px;
  font-weight: 650;
  opacity: .92;
  text-shadow: 0 2px 10px rgba(0,0,0,.35);
}

/* ===== Page ===== */
.page{
  padding: 18px 0 44px;
}

.page-title{
  text-align:center;
  margin: 8px 0 18px;
  font-size: 34px;
  font-weight: 800;
  color: var(--accent);
}

.content{
  width: min(980px, 100%);
  margin: 0 auto;
}

/* ===== About grid ===== */
.about-grid{
  display:grid;
  grid-template-columns: 420px 1fr;  /* bigger photo column */
  gap: 38px;
  align-items: start;
  margin-top: 10px;
}

.profile{
  width: 420px;                     /* bigger photo */
  display:block;
  border-radius: 10px;
}

/* Text blocks */
.section-heading{
  font-weight: 800;
  margin: 0 0 10px;
  font-size: 20px;
}

p{
  margin: 0 0 12px;
}

/* headings like “Work in progress” / “Working papers” */
.section-title{
  font-weight: 800;
  font-size: 18px;
  margin: 22px 0 10px;
}

.hr{
  height: 1px;
  background: var(--accent);
  opacity: .6;
  margin: 10px 0 14px;
}

/* ===== Collapsible paper blocks (your requested UX) =====
   Title
   Coauthors (optional)
   "Abstract" clickable -> opens details
*/
.paper-block{
  border-top: 1px solid var(--border);
  padding: 14px 0;
}

.paper-title{
  font-weight: 800;
  font-size: 16px;
  margin: 0;
}

.paper-coauthors{
  margin-top: 6px;
  color: var(--muted);
  font-size: 14px;
  font-weight: 650;
}

details.paper{
  margin-top: 8px;
}

/* Summary should just look like the word "Abstract" */
details.paper summary{
  cursor: pointer;
  list-style: none;
  width: fit-content;
  color: var(--accent);
  font-weight: 800;
  font-size: 15px;
  text-decoration: underline;
  text-underline-offset: 3px;
}

details.paper summary::-webkit-details-marker{ display:none; }

.paper-abstract{
  margin-top: 10px;
  color: var(--text);
  font-size: 15.5px;
}

/* Plot placeholder on research page */
.plot-placeholder{
  margin-top: 12px;
  border: 1px dashed var(--border);
  border-radius: 12px;
  height: 240px;
  display:flex;
  align-items:center;
  justify-content:center;
  color: var(--muted);
  font-size: 14px;
}

/* ===== Logos row at bottom (bigger logos now) ===== */
.logo-row{
  margin-top: 32px;                 /* bottom spacing */
  display:flex;
  justify-content: space-between;
  align-items: center;
  gap: 18px;
  padding-top: 18px;
  border-top: 1px solid var(--border);
}

.logo{
  height: 64px;                     /* bigger */
  width: auto;
  display:block;
}

.center-block{
  text-align:center;
  font-size: 14px;
  flex: 1;
}

.small-muted{
  color: var(--muted);
  font-size: 13px;
}

/* If logos invert in dark mode and look wrong, remove this block */
html.dark .logo{
  filter: brightness(0) invert(1);
  opacity: .92;
}

/* Footer */
.site-footer{
  padding: 18px 0 6px;
  color: var(--muted);
  font-size: 13px;
  text-align:center;
}

/* ===== Responsive ===== */
@media (max-width: 980px){
  .masthead{ height: 300px; }
  .about-grid{ grid-template-columns: 1fr; }
  .profile{
    width: min(420px, 100%);
    margin: 0 auto;
  }
}

@media (max-width: 820px){
  .masthead{ height: 260px; }
  .banner-caption{ display:none; }

  .navbtn{ display:inline-block; }
  .navlinks{
    display:none;
    position:absolute;
    right: 20px;
    top: calc(var(--navh) - 4px);
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
    background: var(--nav-panel);
    border: 1px solid var(--nav-panel-border);
    padding: 12px;
    border-radius: 14px;
    backdrop-filter: blur(10px);
  }
  .navlinks.open{ display:flex; }

  .logo-row{
    flex-direction: column;
    align-items: center;
  }
}