/* variables del sistema de diseño */
:root {
  --font-main: 'Outfit', 'Inter', sans-serif;
  --color-bg: #030712;
  --color-bg-gradient: linear-gradient(135deg, #030712 0%, #0b1528 100%);
  --color-card-bg: rgba(15, 23, 42, 0.6);
  --color-border: rgba(255, 255, 255, 0.08);
  --color-text-main: #f8fafc;
  --color-text-muted: #94a3b8;
  
  --color-primary: #3b82f6;
  --color-primary-glow: rgba(59, 130, 246, 0.35);
  --color-primary-gradient: linear-gradient(135deg, #3b82f6 0%, #1d4ed8 100%);
  
  --color-secondary: #10b981;
  --color-secondary-glow: rgba(16, 185, 129, 0.35);
  --color-secondary-gradient: linear-gradient(135deg, #10b981 0%, #047857 100%);
  
  --color-accent: #f59e0b;
  --color-accent-glow: rgba(245, 158, 11, 0.35);
  --color-accent-gradient: linear-gradient(135deg, #f59e0b 0%, #b45309 100%);

  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset y estructura base */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: var(--font-main);
  background: var(--color-bg-gradient);
  color: var(--color-text-main);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  overflow-x: hidden;
  position: relative;
}

/* Elementos decorativos de fondo */
.bg-glow-1 {
  position: absolute;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, var(--color-primary-glow) 0%, transparent 70%);
  top: -200px;
  right: -200px;
  z-index: -1;
  border-radius: 50%;
  animation: pulse 10s infinite alternate;
}

.bg-glow-2 {
  position: absolute;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, var(--color-secondary-glow) 0%, transparent 70%);
  bottom: -100px;
  left: -200px;
  z-index: -1;
  border-radius: 50%;
  animation: pulse 12s infinite alternate-reverse;
}

@keyframes pulse {
  0% { transform: scale(1) translate(0, 0); opacity: 0.6; }
  100% { transform: scale(1.1) translate(50px, 30px); opacity: 0.8; }
}

/* Header */
header {
  padding: 2.5rem 2rem 1.5rem;
  text-align: center;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

.logo-container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.logo-icon {
  width: 3rem;
  height: 3rem;
  background: var(--color-primary-gradient);
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  box-shadow: 0 0 20px var(--color-primary-glow);
}

header h1 {
  font-size: 2.5rem;
  font-weight: 800;
  letter-spacing: -0.025em;
  background: linear-gradient(to right, #ffffff, #94a3b8);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 0.5rem;
}

header p {
  color: var(--color-text-muted);
  font-size: 1.1rem;
  font-weight: 400;
  max-width: 600px;
  margin: 0 auto;
}

/* Grid de Proyectos */
main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

.projects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
  width: 100%;
}

/* Tarjetas */
.project-card {
  background: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: 24px;
  padding: 2.5rem 2rem;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.project-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  transition: var(--transition-normal);
}

.project-card.planner::before { background: var(--color-primary-gradient); }
.project-card.solar::before { background: var(--color-secondary-gradient); }
.project-card.rebt::before { background: var(--color-accent-gradient); }

.project-card:hover {
  transform: translateY(-8px);
  border-color: rgba(255, 255, 255, 0.15);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}

.project-card.planner:hover { box-shadow: 0 15px 30px var(--color-primary-glow); }
.project-card.solar:hover { box-shadow: 0 15px 30px var(--color-secondary-glow); }
.project-card.rebt:hover { box-shadow: 0 15px 30px var(--color-accent-glow); }

.card-top {
  margin-bottom: 2rem;
}

.card-icon {
  width: 3.5rem;
  height: 3.5rem;
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.75rem;
  margin-bottom: 1.5rem;
}

.planner .card-icon { background: rgba(59, 130, 246, 0.1); color: #3b82f6; }
.solar .card-icon { background: rgba(16, 185, 129, 0.1); color: #10b981; }
.rebt .card-icon { background: rgba(245, 158, 11, 0.1); color: #f59e0b; }

.card-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: #ffffff;
}

.card-desc {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

.card-features {
  list-style: none;
}

.card-features li {
  font-size: 0.85rem;
  color: #cbd5e1;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.card-features li::before {
  content: '✓';
  font-weight: bold;
}

.planner .card-features li::before { color: #3b82f6; }
.solar .card-features li::before { color: #10b981; }
.rebt .card-features li::before { color: #f59e0b; }

.card-btn {
  width: 100%;
  padding: 1rem;
  border-radius: 12px;
  border: none;
  font-family: var(--font-main);
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: var(--transition-fast);
  text-decoration: none;
}

.planner .card-btn {
  background: var(--color-primary-gradient);
  color: white;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.solar .card-btn {
  background: var(--color-secondary-gradient);
  color: white;
  box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

.rebt .card-btn {
  background: var(--color-accent-gradient);
  color: white;
  box-shadow: 0 4px 12px rgba(245, 158, 11, 0.3);
}

.card-btn:hover {
  filter: brightness(1.1);
  transform: scale(1.02);
}

/* Footer */
footer {
  padding: 2rem;
  text-align: center;
  border-top: 1px solid var(--color-border);
  width: 100%;
}

footer p {
  color: #64748b;
  font-size: 0.85rem;
  font-weight: 500;
}

/* Responsividad */
@media (max-width: 768px) {
  header h1 { font-size: 2rem; }
  main { padding: 1rem; }
  .projects-grid { grid-template-columns: 1fr; }
}