:root{
  --bg-1:#0b0f14;
  --bg-2:#071019;
  --card:#0f1720;
  --muted:#9aa4b2;
  --accent:#7dd3fc;
  --card-shadow: 0 6px 18px rgba(2,6,23,0.6);
  --radius:12px;
  --text:#e6eef6;
}
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  font-family:Inter,Segoe UI,system-ui,Roboto,Arial,sans-serif;
  background:linear-gradient(180deg,var(--bg-1),var(--bg-2));
  color:var(--text);
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}
.site-header{
  text-align:center;
  padding:40px 20px 18px;
  position:relative;
}
.site-header h1{margin:0;font-size:clamp(1.6rem,2.4vw,2.25rem)}
.subtitle{color:var(--muted);margin-top:6px}

.grid{
  display:grid;
  gap:20px;
  padding:28px;
  width:100%;
  max-width:1100px;
  margin:0 auto 40px;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}
.card{
  display:flex;
  flex-direction:column;
  align-items:center;
  text-decoration:none;
  background:linear-gradient(180deg,var(--card), rgba(255,255,255,0.01));
  padding:20px;
  border-radius:var(--radius);
  box-shadow:var(--card-shadow);
  transition:transform .18s ease, box-shadow .18s ease;
}
.card:focus, .card:hover{transform:translateY(-6px);box-shadow:0 18px 32px rgba(2,6,23,0.7)}
.logo{width:96px;height:96px;object-fit:contain;margin-bottom:14px}
.logo-wrap{display:inline-flex;align-items:center;justify-content:center;padding:10px;border-radius:14px;background:rgba(255,255,255,0.02);margin-bottom:10px;box-shadow:0 6px 20px rgba(2,6,23,0.45);border:1px solid rgba(255,255,255,0.03);position:relative;overflow:visible}
.card h2{margin:0;color:var(--text);font-size:1.05rem}
.card p{margin:8px 0 0;color:var(--muted);font-size:0.92rem}

.site-footer{color:var(--muted);text-align:center;padding:20px 10px 40px}

.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}

@media (min-width:1024px){
  .grid{grid-template-columns:repeat(4,1fr)}
}

@media (min-width:640px) and (max-width:1023px){
  .grid{grid-template-columns:repeat(2,1fr)}
}

@media (max-width:639px){
  .grid{grid-template-columns:1fr;padding:16px}
  .logo{width:84px;height:84px}
}

/* Theme toggle button */
.theme-toggle{position:absolute;right:18px;top:18px}
.theme-toggle button{
  background:transparent;border:1px solid rgba(255,255,255,0.06);color:var(--text);padding:8px 10px;border-radius:10px;cursor:pointer;font-size:18px;line-height:1;transition:background .12s ease,transform .08s ease;
}
.theme-toggle button:hover{background:rgba(255,255,255,0.02);transform:translateY(-2px)}

/* Light theme overrides */
.light-theme{
  --bg-1:#e8f1fc;
  --bg-2:#cfe0f5;
  /* pure white card so it clearly separates from the blue-tinted page */
  --card:#ffffff;
  --muted:#425067;
  --accent:#2563eb;
  --card-shadow: 0 10px 26px rgba(30,58,110,0.12);
  --text:#0f1f33;
}

/* Smooth color transitions */
/* Smooth color transitions */
html,body,.card{transition:background-color .18s ease,color .18s ease}

/* Light-mode logo improvements */
.light-theme .card{background:linear-gradient(180deg,var(--card), rgba(255,255,255,0.5));}
.light-theme .logo-wrap{
  /* faint blue-tinted surface so it reads as a distinct layer on the white card */
  background:#f3f7fd;
  border:1px solid rgba(30,58,110,0.08);
  box-shadow:0 6px 16px rgba(30,58,110,0.10);
}
.light-theme .logo{
  /* subtle pop for logos on white */
  filter: drop-shadow(0 3px 6px rgba(16,24,40,0.06)) saturate(1.05) contrast(1.02);
}