/* =========================
   Base (shared)
========================= */
:root{
    --bg: #ffffff;
    --text: #111827;
    --muted: #4b5563;
    --border: #e5e7eb;
    --card: rgba(255,255,255,0.9);
    --shadow: 0 10px 28px rgba(17,24,39,0.08);
    --accent: #c8102e; /* Northeastern red */
  }
  
  *{ box-sizing: border-box; }
  
  html, body{
    margin: 0;
    padding: 0;
    font-family: "Real Head Pro", system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, sans-serif;
    color: var(--text);
    background: var(--bg);
  }
  
  img{ max-width: 100%; height: auto; display: block; }
  
  a{
    color: inherit;
    text-decoration: none;
  }
  
  /* Remove red overlay/box hover behavior (keep subtle underline only where we explicitly add it) */
  a:hover{
    text-decoration: none;
  }
  
  p{ color: var(--muted); line-height: 1.7; }

html {
  height: 100%;
}

body {
  min-height: 100%;
  display: flex;
  flex-direction: column;
}

main {
  flex: 1;
}
  
  /* =========================
     Layout (shared)
  ========================= */
  .page-content{
    width: min(1400px, 92vw);
    margin: 0 auto;
    padding: 36px 0 64px;
  }
  
  /* =========================
     Lab Nav (shared)
  ========================= */
  .lab-nav{
    background: #f8fafc;
    border-bottom: 1px solid var(--border);
  }
  
  .lab-nav-inner{
    /* width: min(1100px, 92vw); */
    width: 100%;
    margin: 0 auto;
    min-height: 58px;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 18px;
    padding: 0px 24px;
  }
  
  .lab-nav a{
    padding: 10px 10px;
    border-radius: 10px;
    font-weight: 500;
    font-size: 15px;
    color: #111827;
  }
  
  .lab-nav a:hover{
    background: rgba(17,24,39,0.06);
  }

  .lab-nav .nav-logo:hover{
    background: none !important;
    opacity: 1;
}
  
  .lab-nav a.active{
    background: rgba(17,24,39,0.10);
  }
  
  @media (max-width: 860px){
    .lab-nav-inner{
      justify-content: center;
      flex-wrap: wrap;
      padding: 10px 0;
    }
  }

  .nav-logo img{
      height: 30px;
      width: auto;
  }

  .lab-nav-inner{
      justify-content: flex-start;
      gap: 18px;
  }

  .nav-logo{
      margin-right: auto;
  }
  
  /* =========================
     Typography (shared)
  ========================= */
  h1, h2, h3, h4{
    margin: 0 0 12px 0;
    color: var(--text);
    letter-spacing: -0.02em;
  }
  
  h1{ font-size: clamp(34px, 4vw, 52px); line-height: 1.05; }
  h2{ font-size: clamp(24px, 2.6vw, 34px); line-height: 1.15; }
  h3{ font-size: 18px; line-height: 1.25; }
  h4{ font-size: 16px; line-height: 1.25; }
  
  /* =========================
     Sections (shared)
  ========================= */
  .section-block{
    padding: 28px 0;
    border-top: 1px solid rgba(17,24,39,0.06);
  }
  
  .section-block:first-child{
    border-top: none;
  }
  
  /* =========================
     Hero (shared)
  ========================= */
  .section-hero{
    padding: 56px 0 34px;
  }
  
  .hero p{
    max-width: 70ch;
    margin: 12px 0 18px;
    font-size: 18px;
  }
  
  /* =========================
     Buttons (shared)
  ========================= */
  .btn-primary{
    display: inline-block;
    padding: 12px 16px;
    border-radius: 999px;
    background: var(--accent);
    color: #fff;
    font-weight: 800;
    box-shadow: 0 10px 25px rgba(200,16,46,0.20);
    transition: transform 0.12s ease, filter 0.12s ease;
  }
  
  .btn-primary:hover{
    filter: brightness(0.95);
    transform: translateY(-1px);
  }

    /* Secondary button */
  .btn-secondary{
    display: inline-block;
    padding: 12px 16px;
    border-radius: 999px;
    background: #ffffff;
    border: 1px solid rgba(15,23,42,0.14);
    color: #111827;
    font-weight: 800;
    box-shadow: 0 10px 25px rgba(15,23,42,0.08);
    transition: transform 0.12s ease, background 0.12s ease;
  }
  
  .btn-secondary:hover{
    background: rgba(15,23,42,0.03);
    transform: translateY(-1px);
  }
  
  /* =========================
     Cards + Grids (shared)
  ========================= */
  .research-grid,
  .project-grid,
  .team-grid{
    display: grid;
    gap: 18px;
    margin-top: 16px;
  }
  
  .research-grid{ grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .project-grid{ grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .team-grid{ grid-template-columns: repeat(3, minmax(0, 1fr)); }
  
  @media (max-width: 900px){
    .research-grid, .project-grid, .team-grid{
      grid-template-columns: repeat(2, minmax(0, 1fr));
    }
  }
  @media (max-width: 620px){
    .research-grid, .project-grid, .team-grid{
      grid-template-columns: 1fr;
    }
  }
  
  .research-card,
  .project-card,
  .team-card{
    background: var(--card);
    border: 1px solid rgba(15,23,42,0.10);
    border-radius: 16px;
    box-shadow: var(--shadow);
    padding: 18px;
  }
  
  .team-card img{
    border-radius: 14px;
    border: 1px solid rgba(15,23,42,0.12);
    margin-bottom: 12px;
  }

/* =========================
   Hamburger Menu
========================= */

.hamburger{
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 10px;
    flex-direction: column;
    gap: 5px;
}

.hamburger span{
    display: block;
    width: 22px;
    height: 2.5px;
    background: #111827;
    border-radius: 2px;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

/* Animate to X when open */
.hamburger[aria-expanded="true"] span:nth-child(1){
    transform: translateY(7.5px) rotate(45deg);
}

.hamburger[aria-expanded="true"] span:nth-child(2){
    opacity: 0;
}

.hamburger[aria-expanded="true"] span:nth-child(3){
    transform: translateY(-7.5px) rotate(-45deg);
}

@media (max-width: 860px){
    .hamburger{
        display: flex;
    }

    .lab-nav-inner{
        justify-content: flex-start;
        flex-wrap: nowrap;
        position: relative;
    }

    .lab-nav-links{
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 100%;
        right: 0;
        background: rgba(255, 255, 255, 0.97);
        backdrop-filter: blur(12px);
        -webkit-backdrop-filter: blur(12px);
        border: 1px solid rgba(15, 23, 42, 0.08);
        border-radius: 16px;
        box-shadow: 0 12px 32px rgba(15, 23, 42, 0.10);
        padding: 10px 0;
        min-width: 200px;
        z-index: 100;
        opacity: 0;
        transform: translateY(-8px);
        pointer-events: none;
        transition: opacity 0.25s ease, transform 0.25s ease;
        margin-top: 8px;
    }

    .lab-nav-links.open{
        opacity: 1;
        transform: translateY(0);
        pointer-events: auto;
    }

    .lab-nav-links a{
        padding: 14px 24px;
        border-radius: 0;
        font-size: 15px;
        transition: background 0.15s ease;
    }

    .lab-nav-links a:hover{
        background: rgba(17, 24, 39, 0.04);
    }

    .lab-nav-links a.active{
        color: var(--accent);
        background: rgba(200, 16, 46, 0.06);
    }
}

/* =========================
   Page Banner (shared)
========================= */

.page-banner{
  position: relative;
  padding: 48px 0 72px;
  background-size: cover;
  background-position: center;
  background-repeat: no-repeat;
}

.page-banner-overlay{
  position: absolute;
  inset: 0;
  background:
    linear-gradient(
      180deg,
      rgba(15,23,42,0.45) 0%,
      rgba(15,23,42,0.30) 50%,
      rgba(15,23,42,0.15) 100%
    );
  pointer-events: none;
}

.page-banner .page-content{
  position: relative;
  z-index: 1;
}

.page-banner + .page-content{
  padding-top: 20px;
}

/* =========================
   Page Hero Card (shared)
========================= */

.page-hero-card{
  max-width: 650px;
  margin-top: 18px;
  border-radius: 28px;
  border: 1px solid rgba(15,23,42,0.10);
  box-shadow: 0 18px 50px rgba(15,23,42,0.12);
  background:
    radial-gradient(900px 380px at 20% 30%, rgba(200,16,46,0.12), transparent 55%),
    radial-gradient(900px 420px at 80% 40%, rgba(59,130,246,0.10), transparent 60%),
    linear-gradient(180deg, #ffffff 0%, #f8fafc 100%);
  padding: 36px;
}

.page-hero-inner{
  max-width: 72ch;
}

.page-hero-card h1{
  font-size: clamp(40px, 4.5vw, 48px);
  line-height: 1.05;
  margin: 0;
  letter-spacing: -0.03em;
}

.page-hero-card p{
  margin: 0 0 22px 0;
  font-size: 18px;
  color: #4b5563;
}

.page-hero-actions{
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  align-items: center;
  margin: 44px 0 0 0;
}

@media (max-width: 720px){
  .page-hero-card{
    padding: 32px 22px;
    border-radius: 22px;
  }
}

/* =========================
   Hero Logo (shared)
========================= */

.hero-logo{
  margin: 0 0 14px 0;
  line-height: 0;
}

.hero-logo-img{
  display: block;
  height: 96px;
  width: auto;
  max-width: 520px;
}

@media (max-width: 900px){
  .hero-logo-img{ height: 80px; }
}

@media (max-width: 600px){
  .hero-logo-img{ height: 64px; max-width: 90%; }
}

/* =========================
   footer logo
========================= */

.lab-footer-logo{
    width: min(1400px, 92vw);
    margin: 0 auto;
    padding: 32px 0;
    border-top: 1px solid var(--border);
}

.lab-footer-logo img{
    height: 80px;
    width: auto;
    opacity: 1;
    transition: opacity 0.2s ease;
}

.lab-footer-logo img:hover{
    opacity: 1;
}
/* =========================
   Floating Home Button (mobile only)
========================= */
.floating-home-btn{
  display: none;
  position: fixed;
  bottom: 24px;
  right: 20px;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  background-color: var(--accent);
  align-items: center;
  justify-content: center;
  z-index: 999;
  box-shadow:
    0 2px 10px rgba(0,0,0,0.18),
    0 0 0 3px rgba(200,16,46,0.12);
  text-decoration: none;
  opacity: 0;
  transform: translateY(12px);
  pointer-events: none;
  transition: opacity 0.35s ease, transform 0.35s ease, background-color 0.2s ease;
}

.floating-home-btn.visible{
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.floating-home-btn:hover{
  background-color: #a00d24;
  box-shadow:
    0 4px 16px rgba(0,0,0,0.22),
    0 0 0 4px rgba(200,16,46,0.18);
}

.floating-home-btn:active{
  transform: scale(0.93);
}

.floating-home-btn svg{
  display: block;
}

@media (max-width: 768px){
  .floating-home-btn{
    display: flex;
  }
}