/* ================================================
   CALCULADORA AI-ALT FUEL — ESTILOS ESPECÍFICOS
   Hereda el Design System de Pixelabs
   ================================================ */

:root {
  --color-primary: oklch(0.5413 0.2466 293.01);
  --color-primary-hover: oklch(0.48 0.22 293.01);
  --color-primary-bg: oklch(0.94 0.035 293.01);
  
  --color-bg-card: oklch(1 0 0);
  --color-bg-hover: oklch(0.985 0.002 264.54);
  --color-border: oklch(0.923 0.006 264.54);
  
  --color-text-primary: oklch(0.208 0.026 264.53);
  --color-text-secondary: oklch(0.373 0.022 264.53);
  --color-text-result: oklch(49.97% 0.00006 271.152);
  --color-text-muted: oklch(0.551 0.015 264.53);

  --radius-sm: 8px;
  --radius-lg: 16px;
  
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.3);

  --font-montserrat: sans-serif;
  --font-source-sans-3: sans-serif;
}

/* ================================================
   RESETEO BÁSICO 
   ================================================ */
* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  background-color: #ffffff;
}

.calculadora-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 24px;
  font-family: var(--font-source-sans-3);
  color: var(--color-text-primary);
}

#title {
  font-family: var(--font-montserrat);
  font-size: 1.4rem;
  font-weight: 900;
  margin-bottom: 0;
  background: linear-gradient(135deg, var(--color-primary), #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}

/* ================================================
   TOP HEADER (Navegación Superior)
   ================================================ */
.top-header {
  background-color: #d4d4d8;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 48px;
  background-color: #f8f9fa;
  position: relative;
}

.header-logo img {
  height: 36px;
  width: auto;
  display: block;
}

.header-nav {
  display: flex;
  gap: 32px;
}

.header-nav a {
  text-decoration: none;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-text-primary);
  font-family: var(--font-source-sans-3);
  transition: color 0.2s ease;
}

.header-nav a:hover {
  color: var(--color-primary);
}
.header-title {
  position: absolute;
  right: 48px;
}

.header-nav a.active {
  color: var(--color-primary); 
}


.main-content {
  padding-top: 32px;
  background-color: #ffffff;
}

/* ================================================
   TARJETAS DE SECCIÓN (Cajas contenedoras)
   ================================================ */
.seccion-calculadora {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 32px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-sm);
}

.seccion-calculadora h2 {
  font-size: 1.25rem;
  font-weight: 800;
  color: var(--color-text-primary);
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-bg-hover);
}

/* ================================================
   CAJA DE DESCRIPCIÓN (Callout de instrucciones)
   ================================================ */
.calculadora-descripcion {
  background-color: var(--color-primary-bg);
  border-left: 4px solid var(--color-primary);
  padding: 16px 20px;
  margin-bottom: 32px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.calculadora-descripcion p {
  color: var(--color-primary);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.6;
  margin-bottom: 8px;
}

.calculadora-descripcion p:last-child {
  margin-bottom: 0;
}

/* ================================================
   GRILLAS DE CONTENIDO (La magia visual)
   ================================================ */
#contenedor-entradas,
#contenedor-calculos {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 20px;
}

#contenedor-bloques {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 32px;
}

/* ================================================
   ELEMENTOS INTERNOS (Inputs y Labels)
   ================================================ */
.entrada-item,
.campo-bloque,
.calculo-item {
  display: flex;
  flex-direction: column;
  position: relative;
}

.bloque-item h3 {
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.info-bloque {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.entrada-item label,
.campo-bloque label,
.calculo-item label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-text-secondary);
  margin-bottom: 6px;
  min-height: 20px;
}

.entrada-item input,
.campo-bloque input,
.calculo-item input {
  width: 100%;
  padding: 12px 85px 12px 14px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  color: var(--color-primary);
  font-size: 15px;
  font-weight: 800;
  font-family: var(--font-source-sans-3);
  transition: all 0.2s ease;
  box-shadow: inset 0 1px 2px rgba(0,0,0,0.02);
  margin-top: auto;
}

.entrada-item input:focus,
.campo-bloque input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-bg);
}

.unidad {
  position: absolute;
  right: 14px;
  bottom: 1px;
  height: 42px;
  display: flex;
  align-items: center;
  font-size: 13px;
  font-weight: 700;
  color: var(--color-text-muted);
  pointer-events: none;
}

/* ================================================
   ESTADO READONLY (Campos Calculados)
   ================================================ */

input[readonly] {
  background: var(--color-bg-hover);
  color: var(--color-text-result) !important;
  border-color: transparent !important;
  box-shadow: none !important;
  pointer-events: none; 
  user-select: none;
}

input[readonly]:focus {
  outline: none !important;
}

.calculo-item input[readonly] {
  font-size: 16px;
}

/* ================================================
   BOTÓN CALCULAR (Estilo Premium)
   ================================================ */

.boton-contenedor {
  display: flex;
  justify-content: flex-end;
  gap: 16px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
  margin-bottom: 32px;
}

#btn-reset {
  background: transparent;
  color: var(--color-text-secondary);
  border: 2px solid var(--color-border);
  padding: 16px 24px;
  font-size: 15px;
  font-weight: 700;
  font-family: var(--font-montserrat);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all 0.3s ease;
  display: flex;
  align-items: center;
  gap: 10px;
}

#btn-reset:hover {
  border-color: var(--color-text-primary);
  color: var(--color-text-primary);
  background: var(--color-bg-hover);
}

#btn-calcular {
  background: var(--color-primary);
  color: white;
  border: none;
  padding: 16px 32px;
  font-size: 16px;
  font-weight: 800;
  font-family: var(--font-montserrat);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  gap: 12px;
}

#btn-calcular:hover {
  background: var(--color-primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(99, 102, 241, 0.4);
}

#btn-calcular:active {
  transform: translateY(0);
  box-shadow: var(--shadow-sm);
}

input[type="number"]::-webkit-inner-spin-button,
input[type="number"]::-webkit-outer-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

/* Para Firefox */
input[type="number"] {
  -moz-appearance: textfield;
  appearance: textfield;
}

/* ================================================
   FOOTER (Pie de página oscuro)
   ================================================ */
.bottom-footer {
  background-color: #000000;
  color: #ffffff;
  padding: 80px 48px;
  display: flex;
  justify-content: center;
  border-top: 1px solid #1f1f1f;
}

.footer-container {
  max-width: 1200px;
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 24px;
}

.footer-logo {
  height: 48px;
  width: auto;
  display: block;
}

.footer-description {
  font-size: 16px;
  line-height: 1.8;
  color: #d4d4d8;
  font-family: var(--font-source-sans-3);
  margin: 0;
}

.footer-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: #ffffff;
  text-decoration: none;
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.05em;
  font-family: var(--font-montserrat);
  margin-top: 8px;
}

.footer-link svg {
  transition: transform 0.2s ease;
}

.footer-link:hover svg {
  transform: translateX(4px);
}

/* ================================================
   RESPONSIVO MÓVIL
   ================================================ */
@media (max-width: 768px) {
  .calculadora-container {
    padding: 16px;
  }
  
  .seccion-calculadora {
    padding: 20px 16px;
  }
  
  #contenedor-bloques {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .boton-contenedor {
    flex-direction: column-reverse;
    gap: 12px;
  }
  
  #btn-calcular, 
  #btn-reset {
    width: 100%;
    justify-content: center;
  }

  .bottom-footer {
    padding: 48px 24px;
  }
}

/* ================================================
   MODAL DE LOGIN
   ================================================ */
.login-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: #CCCCCC66;
  backdrop-filter: blur(4px);
  z-index: 9999;
  display: flex;
  justify-content: center;
  align-items: center;
  transition: opacity 0.3s ease;
}

.login-card {
  background: var(--color-bg-card);
  padding: 48px 40px;
  border-radius: var(--radius-lg);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  width: 100%;
  max-width: 400px;
  text-align: center;
  border: 1px solid var(--color-border);
}

.login-card .login-subtitle {
  color: var(--color-text-secondary);
  margin-bottom: 20px;
  font-size: 15px;
}

.login-card .login-help {
  background-color: var(--color-bg-hover);
  padding: 12px 16px;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  font-size: 13px;
  margin-bottom: 32px;
  border: 1px solid var(--color-border);
  line-height: 1.5;
}

.login-card .login-help a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 700;
  transition: all 0.2s ease;
}

.login-card .login-help a:hover {
  color: var(--color-primary-hover);
  text-decoration: underline;
}

.login-logo {
  height: 40px;
  margin-bottom: 24px;
}

.login-card h2 {
  color: var(--color-primary);
  margin-bottom: 8px;
  font-family: var(--font-montserrat);
  font-weight: 800;
  font-size: 24px;
}

.login-card p {
  color: var(--color-text-secondary);
  margin-bottom: 32px;
  font-size: 15px;
}

.login-campo {
  text-align: left;
  margin-bottom: 20px;
}

.login-campo label {
  display: block;
  font-size: 13px;
  font-weight: 700;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
}

.login-campo input {
  width: 100%;
  padding: 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-family: var(--font-source-sans-3);
  font-size: 15px;
  color: var(--color-text-primary);
  background: #f8f9fa;
  transition: all 0.2s ease;
}

.login-campo input:focus {
  outline: none;
  border-color: var(--color-primary);
  background: white;
  box-shadow: 0 0 0 3px var(--color-primary-bg);
}

.login-error {
  color: #ef4444 !important; /* Rojo de error */
  font-weight: 600;
  margin-bottom: 20px !important;
  display: none; /* Oculto hasta que se equivoquen */
}

.btn-login {
  width: 100%;
  background: var(--color-primary);
  color: white;
  border: none;
  padding: 16px;
  font-size: 16px;
  font-weight: 800;
  font-family: var(--font-montserrat);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-login:hover {
  background: var(--color-primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 16px rgba(99, 102, 241, 0.3);
}