:root{
  --bg: #f7fafc;
  --card: #ffffff;
  --muted: #6b7280;
  --accent: #0ea5a4;
  --radius: 12px;
  --container-width: 1100px;

  --fs-base: 16px;
  --ff: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
}

*{box-sizing:border-box}
html{font-size:16px}
body{
  margin:0;
  font-family:var(--ff);
  font-size:1rem;
  line-height:1.5;
  color:#0f172a;
  background:var(--bg);
}

/* container central */
.container{
  width:90%;
  max-width:var(--container-width);
  margin:0 auto;
}

/* header */
.site-header{
  background:transparent;
  position:sticky;
  top:0;
  z-index:50;
  backdrop-filter: blur(4px);
}
.header-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  padding:1rem 0;
}
.logo{font-weight:700; text-decoration:none; color:inherit; font-size:1.125rem}
.main-nav ul{display:flex; gap:1rem; list-style:none; margin:0; padding:0; align-items:center}
.main-nav a{ text-decoration:none; color:inherit; padding:0.5rem 0.75rem; display:inline-block}
.btn{display:inline-block; padding:0.5rem 0.9rem; border-radius:8px; text-decoration:none; font-weight:600}
.btn-primary{background:var(--accent); color:white}

/* mobile nav toggle */
.nav-toggle{display:none; background:none; border:0; font-size:1.25rem}

/* hero */
.hero{padding:3.5rem 0}
.hero-inner{display:grid; grid-template-columns:1fr 480px; gap:2rem; align-items:center}
.hero h1{font-size:clamp(1.5rem,2.5vw,2.25rem); margin:0 0 0.5rem}
.hero p{color:var(--muted); margin:0 0 1rem}

/* image */
.hero-image img{width:100%; height:auto; border-radius:var(--radius); box-shadow:0 6px 22px rgba(2,6,23,0.08)}

/* cards */
.cards{display:grid; grid-template-columns:repeat(3,1fr); gap:1.25rem; margin:3rem auto}
.card{
  background:var(--card);
  padding:1.25rem;
  border-radius:12px;
  box-shadow:0 6px 20px rgba(2,6,23,0.04);
  text-align:center;
}
.card img{width:56px; height:56px; margin-bottom:0.75rem}

/* footer */
.site-footer{padding:2rem 0; color:var(--muted); text-align:center}

/* responsive */
@media (max-width:1000px){
  .hero-inner{grid-template-columns:1fr 1fr}
  .cards{grid-template-columns:repeat(2,1fr)}
}
@media (max-width:680px){
  .hero-inner{grid-template-columns:1fr; gap:1.5rem}
  .main-nav ul{flex-direction:column; background:var(--card); position:absolute; right:1rem; top:64px; padding:1rem; border-radius:8px; display:none}
  .main-nav.open ul{display:flex}
  .nav-toggle{display:block}
  .cards{grid-template-columns:1fr}
}
/* ===== Buttons ===== */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  font-weight: 600;
  font-size: 1rem;
  border-radius: 9999px; /* pill shape */
  text-decoration: none;
  text-align: center;
  transition: all 0.3s ease;
  cursor: pointer;
  border: none;
}

/* Primary button */
.btn-primary {
  background: var(--accent, #0ea5a4);
  color: white;
  box-shadow: 0 4px 12px rgba(14, 165, 164, 0.4);
}
.btn-primary:hover {
  background: #089c9b;
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(14, 165, 164, 0.5);
}

/* Outline button */
.btn-outline {
  color: var(--accent, #0ea5a4);
  border: 2px solid var(--accent, #0ea5a4);
  background: transparent;
}
.btn-outline:hover {
  background: var(--accent, #0ea5a4);
  color: white;
  transform: translateY(-2px);
}

/* Gradient button */
.btn-gradient {
  color: white;
  background: linear-gradient(135deg, #06b6d4, #3b82f6);
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}
.btn-gradient:hover {
  filter: brightness(1.1);
  transform: translateY(-2px) scale(1.03);
}

/* Glass button */
.btn-glass {
  background: rgba(255,255,255,0.15);
  color: white;
  border: 1px solid rgba(255,255,255,0.25);
  backdrop-filter: blur(6px);
}
.btn-glass:hover {
  background: rgba(255,255,255,0.25);
  transform: translateY(-2px);
}

/* Optional small/large sizes */
.btn-sm { padding: 0.5rem 1rem; font-size: 0.9rem; }
.btn-lg { padding: 1rem 2rem; font-size: 1.125rem; }