* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

body {
  background-color: #f7fafc;
  color: #2d3748;
}

.header {
  background-color: #ffffff;
  padding: 15px 30px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.header .logo span {
  font-weight: bold;
  font-size: 1.2rem;
  color: #2c3e50;
}

.btn-volver {
  color: #3182ce;
  text-decoration: none;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: color 0.2s;
}

.btn-volver:hover {
  color: #2b6cb0;
}

.container {
  max-width: 950px;
  margin: 30px auto;
  padding: 0 20px;
}

.main-card {
  background: #ffffff;
  border-radius: 12px;
  box-shadow: 0 4px 20px rgba(0,0,0,0.06);
  overflow: hidden;
}

/* TABS HEADER */
.tabs-header {
  display: flex;
  background: #edf2f7;
  border-bottom: 2px solid #e2e8f0;
  flex-wrap: wrap;
}

.tab-btn {
  flex: 1;
  min-width: 180px;
  padding: 16px 12px;
  border: none;
  background: transparent;
  font-size: 0.9rem;
  font-weight: 600;
  color: #718096;
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.tab-btn:hover {
  color: #2d3748;
  background: #e2e8f0;
}

.tab-btn.active {
  background: #ffffff;
  color: #3182ce;
  border-bottom: 3px solid #3182ce;
}

/* BODY CONTENT */
.tabs-body {
  padding: 30px;
}

.tabs-body h2 {
  font-size: 1.4rem;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.tabs-body .sub {
  color: #718096;
  font-size: 0.9rem;
  margin-bottom: 15px;
}

hr {
  border: none;
  border-top: 1px solid #edf2f7;
  margin-bottom: 25px;
}

/* FORMULARIOS */
.grid-form {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 18px;
  margin-bottom: 20px;
}

.input-group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.input-group label {
  font-size: 0.85rem;
  font-weight: 600;
  color: #4a5568;
}

.input-group input, .input-group select {
  padding: 10px 12px;
  border: 1px solid #cbd5e0;
  border-radius: 6px;
  font-size: 0.95rem;
  outline: none;
  transition: border-color 0.2s;
}

.input-group input:focus, .input-group select:focus {
  border-color: #3182ce;
}

.btn-calcular {
  background: #3182ce;
  color: #ffffff;
  border: none;
  padding: 12px 24px;
  border-radius: 8px;
  font-weight: bold;
  font-size: 1rem;
  cursor: pointer;
  transition: background 0.2s;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn-calcular:hover {
  background: #2b6cb0;
}

/* RESULTADOS */
.resultado-box {
  margin-top: 30px;
  background: #f8fafc;
  border: 1px solid #e2e8f0;
  border-radius: 8px;
  padding: 20px;
  animation: fadeIn 0.3s ease;
}

.resultado-box h3 {
  font-size: 1.1rem;
  margin-bottom: 15px;
  color: #2d3748;
}

.resumen-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
  margin-bottom: 20px;
}

.resumen-grid div {
  font-size: 0.9rem;
  color: #4a5568;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.resumen-grid strong {
  font-size: 1.05rem;
  color: #2d3748;
}

.total-destacado {
  background: #ebf8ff;
  border: 1px solid #bee3f8;
  border-radius: 8px;
  padding: 15px;
  text-align: center;
}

.total-destacado span {
  font-size: 0.9rem;
  color: #2b6cb0;
  font-weight: 600;
}

.total-destacado h2 {
  font-size: 1.8rem;
  color: #2b6cb0;
  margin-top: 4px;
  justify-content: center;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}