/* ==========================================================================
   VARIABLES GLOBALES (Diseño Agnóstico y Escalable)
   ========================================================================== */
   :root {
    /* Paleta de Colores (Tema Claro por defecto) */
    --hue-navy: 215;
    --color-bg: hsl(var(--hue-navy), 20%, 96%);
    --color-surface: hsl(var(--hue-navy), 20%, 100%);
    --color-text-main: hsl(var(--hue-navy), 40%, 15%);
    --color-text-muted: hsl(var(--hue-navy), 20%, 45%);
    --color-border: hsl(var(--hue-navy), 20%, 85%);
    
    --color-primary: hsl(var(--hue-navy), 60%, 40%);
    --color-primary-hover: hsl(var(--hue-navy), 60%, 30%);
    --color-success: hsl(140, 50%, 45%);
    --color-danger: hsl(350, 60%, 50%);
    --color-inactive: hsl(var(--hue-navy), 10%, 80%);

    /* Tipografía (Escalado fluido con Clamp) */
    --font-family: 'Segoe UI', system-ui, -apple-system, sans-serif;
    --text-xs: clamp(0.75rem, 1vw, 0.875rem);
    --text-sm: clamp(0.875rem, 1.5vw, 1rem);
    --text-md: clamp(1rem, 2vw, 1.125rem);
    --text-lg: clamp(1.25rem, 2.5vw, 1.5rem);
    --text-xl: clamp(1.5rem, 3vw, 2rem);
    --text-2xl: clamp(2rem, 5vw, 3rem);

    /* Espaciado */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;

    /* Bordes y Sombras */
    --rad-sm: 0.5rem;
    --rad-md: 1rem;
    --rad-lg: 1.5rem;
    --rad-full: 9999px;
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
    
    /* Transiciones */
    --trans-fast: 0.15s ease;
    --trans-normal: 0.3s ease;
}

/* Tema Oscuro (Navy) - Se activa con [data-theme="dark"] o preferencia del sistema */
@media (prefers-color-scheme: dark) {
    :root {
        --color-bg: hsl(var(--hue-navy), 40%, 10%);
        --color-surface: hsl(var(--hue-navy), 40%, 15%);
        --color-text-main: hsl(var(--hue-navy), 20%, 95%);
        --color-text-muted: hsl(var(--hue-navy), 20%, 70%);
        --color-border: hsl(var(--hue-navy), 30%, 25%);
        --color-inactive: hsl(var(--hue-navy), 20%, 25%);
    }
}

[data-theme="dark"] {
    --color-bg: hsl(var(--hue-navy), 40%, 10%);
    --color-surface: hsl(var(--hue-navy), 40%, 15%);
    --color-text-main: hsl(var(--hue-navy), 20%, 95%);
    --color-text-muted: hsl(var(--hue-navy), 20%, 70%);
    --color-border: hsl(var(--hue-navy), 30%, 25%);
    --color-inactive: hsl(var(--hue-navy), 20%, 25%);
}

/* ==========================================================================
   RESET & BASE
   ========================================================================== */
* { box-sizing: border-box; margin: 0; padding: 0; }
body {
    font-family: var(--font-family);
    background-color: var(--color-bg);
    color: var(--color-text-main);
    line-height: 1.5;
    transition: background-color var(--trans-normal), color var(--trans-normal);
    -webkit-font-smoothing: antialiased;
}

/* ==========================================================================
   CLASES UTILITARIAS (Estilo Tailwind)
   ========================================================================== */
/* Layout */
.w-full { width: 100%; }
.max-w-screen { max-width: 600px; margin: 0 auto; }
.min-h-screen { min-height: 100vh; }
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.gap-xs { gap: var(--space-xs); }
.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }

/* Spacing */
.p-sm { padding: var(--space-sm); }
.p-md { padding: var(--space-md); }
.py-md { padding-top: var(--space-md); padding-bottom: var(--space-md); }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }

/* Typography */
.text-center { text-align: center; }
.text-xs { font-size: var(--text-xs); }
.text-sm { font-size: var(--text-sm); }
.text-md { font-size: var(--text-md); }
.text-lg { font-size: var(--text-lg); font-weight: 600; }
.text-xl { font-size: var(--text-xl); font-weight: 700; }
.text-2xl { font-size: var(--text-2xl); font-weight: 300; letter-spacing: 2px; }
.text-muted { color: var(--color-text-muted); }
.text-primary { color: var(--color-primary); }
.uppercase { text-transform: uppercase; }

/* Visuals */
.bg-surface { background-color: var(--color-surface); }
.rounded-md { border-radius: var(--rad-md); }
.rounded-lg { border-radius: var(--rad-lg); }
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.border { border: 1px solid var(--color-border); }
.overflow-hidden { overflow: hidden; }

/* ==========================================================================
   COMPONENTES ESPECÍFICOS
   ========================================================================== */
/* Cámara */
.camera-wrapper {
    position: relative;
    width: 100%;
    aspect-ratio: 3/4;
    background-color: #000;
}
.camera-wrapper video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transform: scaleX(-1); /* Efecto espejo */
}
.camera-overlay {
    position: absolute;
    inset: 0;
    pointer-events: none;
    display: flex;
    align-items: center;
    justify-content: center;
}
.camera-guide {
    width: 60%;
    height: 50%;
    border: 2px dashed rgba(255,255,255,0.5);
    border-radius: 50% 50% 40% 40%;
    animation: pulse 2s infinite;
}

/* Botones */
.btn {
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--rad-md);
    border: none;
    font-size: var(--text-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--trans-fast);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    position: relative;
    overflow: hidden;
}
.btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: white;
    opacity: 0;
    transition: opacity var(--trans-fast);
}
.btn:active::after { opacity: 0.2; }

.btn-primary { background-color: var(--color-primary); color: white; }
.btn-success { background-color: var(--color-success); color: white; }
.btn-success:hover { box-shadow: 0 0 15px var(--color-success); }
.btn-outline { background-color: transparent; border: 2px solid var(--color-border); color: var(--color-text-main); }

/* Toggle Buttons (Entrada/Salida) */
.toggle-group { display: flex; gap: var(--space-sm); width: 100%; }
.toggle-btn {
    flex: 1;
    background-color: var(--color-surface);
    border: 2px solid var(--color-inactive);
    color: var(--color-text-muted);
}
.toggle-btn[data-state="active"][data-type="entrada"] {
    background-color: var(--color-success);
    border-color: var(--color-success);
    color: white;
}
.toggle-btn[data-state="active"][data-type="salida"] {
    background-color: var(--color-danger);
    border-color: var(--color-danger);
    color: white;
}

/* Inputs */
.input-field {
    width: 100%;
    padding: var(--space-sm);
    border: 1px solid var(--color-border);
    border-radius: var(--rad-sm);
    background-color: var(--color-bg);
    color: var(--color-text-main);
    font-size: var(--text-md);
    transition: border-color var(--trans-fast);
}
.input-field:focus { outline: none; border-color: var(--color-primary); }

/* Toasts (Notificaciones Modernas) */
.toast-container {
    position: fixed;
    bottom: var(--space-md);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
    z-index: 9999;
    width: 90%;
    max-width: 400px;
}
.toast {
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--rad-sm);
    color: white;
    font-weight: 600;
    font-size: var(--text-sm);
    text-align: center;
    box-shadow: var(--shadow-md);
    animation: slideUp var(--trans-normal) forwards;
}
.toast.success { background-color: var(--color-success); }
.toast.error { background-color: var(--color-danger); }
.toast.info { background-color: var(--color-primary); }

/* Animaciones */
@keyframes pulse {
    0% { transform: scale(0.95); opacity: 0.5; }
    50% { transform: scale(1); opacity: 1; }
    100% { transform: scale(0.95); opacity: 0.5; }
}
@keyframes slideUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/*
MEJORAS DE DISEÑO v1.0.0.:
Puro CSS / Sin librerías externas pesadas: Tienes la estructura mental de Tailwind (clases como flex-col, gap-sm), pero procesado nativamente por el navegador usando variables de CSS.

Tema Oscuro Inteligente: Si el celular del guardia está en modo oscuro para la guardia nocturna, la interfaz se pondrá azul marino profundo automáticamente para no lastimar los ojos.
*/