/* ===== Base ===== */
* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background-color: #0f0a1f;
  color: #ffffff;
  line-height: 1.6;
  scroll-behavior: smooth;
}
main section { scroll-margin-top: 120px; }

h1, h2, h3 { margin: 0 0 1rem 0; }
p { color: #d1d5db; margin: 0 auto 1.25rem; max-width: 900px; }

/* ===== Header fijo con animación ===== */
#mainHeader {
  position: fixed;
  top: 0; left: 0; width: 100%;
  display: flex; justify-content: space-between; align-items: center;
  padding: 20px 40px;
  background: rgba(15,10,31,0.55);
  border-bottom: 1px solid rgba(255,255,255,0.08);
  backdrop-filter: saturate(120%) blur(6px);
  transition: padding .3s ease, background .3s ease, box-shadow .3s ease;
  z-index: 1000;
}
#mainHeader .logo-container { display: flex; align-items: center; gap: .5rem; }
#mainHeader .logo { height: 56px; transition: height .3s ease; }
#mainHeader .logo-text { font-weight: 700; letter-spacing: .5px; }

/* Al dejar de ver el hero, el header gana presencia y el logo crece */
#mainHeader.scrolled { background: #111; padding: 12px 40px; box-shadow: 0 6px 20px rgba(0,0,0,.35); }
#mainHeader.scrolled .logo { height: 76px; }

/* ===== Nav ===== */
#mainNav a { color: #fff; text-decoration: none; margin-left: 1.25rem; padding-bottom: 4px; transition: color .2s ease, border-color .2s ease; border-bottom: 2px solid transparent; }
#mainNav a:hover { color: #60a5fa; }
#mainNav a.active { color: #60a5fa; border-color: #60a5fa; }

/* ===== Hero / Slider ===== */
.hero { min-height: 100vh; display: grid; place-items: center; text-align: center; position: relative; padding: 0 1.25rem; }
.hero-slider { width: min(1100px, 92vw); }
.hero-slider .slide { display: none; animation: fade 700ms ease-in-out; }
.hero-slider .slide.active { display: block; }
.hero-logo { width: 160px; opacity: .95; filter: drop-shadow(0 10px 20px rgba(0,0,0,.35)); }
.hero-logo.grande { width: 220px; margin-bottom: 12px; }
@keyframes fade { from { opacity: 0 } to { opacity: 1 } }

/* ===== Secciones ===== */
section { padding: 6rem 1.5rem; text-align: center; }
.bg-alt { background-color: #171029; }

/* ===== Botón ===== */
.btn { background: linear-gradient(90deg, #3b82f6, #9333ea); color: #fff; padding: .85rem 1.5rem; border-radius: 14px; border: none; cursor: pointer; font-size: 1rem; box-shadow: 0 10px 24px rgba(0,0,0,.35); transition: transform .15s ease, opacity .2s ease; text-decoration: none;}
.btn:hover { opacity: .92; transform: translateY(-2px); }

/* ===== Cards ===== */
.cards { display: grid; gap: 1.5rem; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); max-width: 1100px; margin: 2rem auto 0; }
.card { background: #171029; border-radius: 16px; padding: 1.5rem; text-align: left; box-shadow: 0 8px 24px rgba(0,0,0,.35); border: 1px solid rgba(255,255,255,0.06); }
.card h3 { margin-bottom: .5rem; }

/* ===== Formulario de contacto ===== */
.contact-form { max-width: 640px; margin: 0 auto; display: grid; gap: 1rem; }
.contact-form input, .contact-form textarea { width: 100%; padding: .85rem 1rem; border-radius: 12px; background: #0f0a1f; border: 1px solid #374151; color: #fff; }
.contact-form input:focus, .contact-form textarea:focus { outline: none; border-color: #60a5fa; box-shadow: 0 0 0 3px rgba(96,165,250,.15); }
.form-message { margin-top: 1rem; font-weight: 600; }
.form-message.success { color: #34d399; }
.form-message.error { color: #f87171; }

/* ===== Footer ===== */
footer { text-align: center; padding: 2rem 1.5rem; border-top: 1px solid rgba(255,255,255,0.08); color: #9ca3af; }

/* ===== Utilidades ===== */
.hide { display: none !important; }