:root { --bg:#0f1115; --fg:#e6e6e6; --muted:#9aa1ac; --accent:#7df; }
 *{box-sizing:border-box} html,body{margin:0;padding:0;background:var(--bg);color:var(--fg);font:16px/1.6 system-ui,-apple-system,Segoe UI,Roboto,Inter,Arial}
 a{color:var(--accent);text-decoration:none} a:hover{text-decoration:underline}
 .wrap{max-width:960px;margin:0 auto;padding:40px 20px}
 header{display:flex;align-items:center;justify-content:space-between;gap:16px}
 nav a{margin-left:16px}
 .hero{padding:80px 0}
 h1{font-size: clamp(32px, 6vw, 56px); margin:0 0 12px}
 .sub{color:var(--muted);max-width:60ch}
 .cta{margin-top:24px;display:flex;gap:12px;flex-wrap:wrap}
 .btn{padding:12px 18px;border:1px solid var(--accent);border-radius:8px}
 .grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:16px;margin-top:36px}
 .card{border:1px solid #222;border-radius:12px;padding:16px;background:#12151b}
 h2{margin-top:48px}
 footer{margin-top:64px;padding-top:24px;border-top:1px solid #222;color:var(--muted);font-size:14px}
 code{background:#0b0d12;padding:2px 6px;border-radius:6px}

 .btn {
  padding: 12px 18px;
  border: 1px solid var(--accent);
  border-radius: 8px;
  transition: all 0.25s ease;
}

.btn:hover {
  background: var(--accent);
  color: #000;
  transform: translateY(-2px);
  box-shadow: 0 0 8px var(--accent);
}

nav a {
  position: relative;
  margin-left: 16px;
}

nav a::after {
  content: "";
  position: absolute;
  bottom: -3px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent);
  transition: width 0.25s ease;
}

nav a:hover::after {
  width: 100%;
}

.hero {
  padding: 80px 0;
  text-align: center;                 /* center inline content */
  display: flex;                      /* center the block itself */
  flex-direction: column;
  align-items: center;                /* horizontally center children */
  gap: 12px;                          /* nice breathing room */
}

/* Center + style the photo */
.profile-photo {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--accent);
  box-shadow: 0 0 12px rgba(125, 255, 255, 0.25);
  display: block;
}

/* Keep the paragraph a readable width and centered */
.sub {
  max-width: 60ch;
  margin: 0 auto;
}

/* Center the buttons row */
.cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}


/* --- Mobile-first improvements --- */

/* Buttons: comfy tap targets */
.btn {
  padding: 14px 18px;         /* >=44px total height with line-height */
  min-height: 44px;
  text-align: center;
}

/* Tighter layout on small screens */
@media (max-width: 640px) {
  html, body { font-size: 15px; }               /* slight scale for small screens */
  .wrap { padding: 24px 16px; }                 /* less side padding */
  header { flex-direction: column; align-items: flex-start; gap: 8px; }
  nav { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 4px; }
  nav a { margin-left: 0; }                     /* reset the desktop left-margin */

  .hero { padding: 48px 0; }
  h1 { font-size: clamp(28px, 8vw, 40px); }     /* scale headline down nicely */
  .sub { max-width: 100%; }                     /* no cramped text columns */

  .cta { flex-direction: column; gap: 10px; }   /* stack buttons */
  .btn { width: 100%; }                         /* full-width tap targets */

  .grid { grid-template-columns: 1fr; }         /* one card per row */
  .card { padding: 14px; }
  h2 { margin-top: 36px; }
  footer { margin-top: 40px; }
}

/* Medium screens: 2-up cards */
@media (min-width: 641px) and (max-width: 960px) {
  .grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (max-width: 640px) {
  .hero-content {
    flex-direction: column;
    text-align: center;
  }

  .profile-photo {
    width: 120px;
    height: 120px;
  }
}