/* ================================================================
   ESTILOS COMPARTIDOS - BEST NUTRITION
================================================================
   1. VARIABLES .............. (Línea 14)
   2. BASE & RESET ........... (Línea 32)
   3. HEADER & LOGO .......... (Línea 47)
   4. NAVEGACIÓN ............. (Línea 75)
   5. COMPONENTES COMUNES .... (Línea 102)
   6. FOOTER ................. (Línea 140)
   7. BOTÓN SCROLL TOP ....... (Línea 186)
================================================================ */

/* 1. VARIABLES */
:root {
    --color-primary:      #0071e3;
    --color-primary-hover: #005cbf;
    --color-text:         #1d1d1f;
    --color-text-muted:   #86868b;
    --color-text-body:    #424245;
    --color-bg:           #fafafa;
    --color-bg-white:     #ffffff;
    --color-bg-subtle:    #f5f5f7;
    --color-border:       #d2d2d7;
    --color-border-light: rgba(210, 210, 215, 0.4);
    --color-badge-bg:     #e0f2fe;
    --color-disabled:     #c5c5c7;
    --color-success:      #16a34a;
    --color-error:        #d93025;
    --color-track-bg:     #e8e8ed;
    --color-selected-bg:  #f0f7ff;
    --color-icon-bg:      #e8f1fc;
}

/* 2. BASE & RESET */
*, *::before, *::after {
    box-sizing: border-box;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--color-bg);
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    color: var(--color-text);
}

h1 {
    text-align: center;
    font-weight: 600;
    font-size: 32px;
    color: var(--color-text);
    margin-top: 40px;
    text-transform: uppercase;
}

/* 3. HEADER & LOGO */
header {
    width: 100%;
    padding: 40px 20px 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    background-color: var(--color-bg);
}

.logo-link {
    display: flex;
    justify-content: center;
    align-items: center;
    text-decoration: none;
}

header img {
    height: 130px;
    width: auto;
    max-width: 90%;
    object-fit: contain;
    display: block;
    transition: opacity 0.2s ease;
}

header img:hover { opacity: 0.8; }

/* 4. NAVEGACIÓN */
nav ul {
    display: flex;
    justify-content: center;
    list-style: none;
    gap: 30px;
    background-color: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 20px;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.05);
    padding: 15px 35px;
    margin: 0 auto 50px auto;
    width: fit-content;
}

nav ul li a {
    text-decoration: none;
    color: var(--color-text);
    font-size: 14px;
    font-weight: 500;
    letter-spacing: -0.01em;
    transition: color 0.3s ease;
}

nav ul li a:hover,
nav ul li a.active { color: var(--color-primary); }
nav ul li a.active { font-weight: 700; }

/* 5. COMPONENTES COMUNES (usados en varias páginas) */

/* Etiqueta pequeña azul de sección */
.tagline {
    color: var(--color-primary);
    font-weight: 600;
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

/* Texto secundario debajo del título */
.subtitle {
    color: var(--color-text-muted);
    font-size: 19px;
    margin-bottom: 50px;
}

/* Botón principal azul */
.cta-button {
    display: block;
    background-color: var(--color-primary);
    color: white;
    padding: 16px;
    border-radius: 14px;
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
    text-align: center;
    transition: background-color 0.2s ease;
    cursor: pointer;
    border: none;
    font-family: inherit;
}

.cta-button:hover { background-color: var(--color-primary-hover); }

/* Etiqueta "badge" sobre las cards */
.badge {
    position: absolute;
    top: 12px;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--color-badge-bg);
    color: var(--color-primary);
    padding: 6px 16px;
    font-size: 10px;
    font-weight: 700;
    text-transform: uppercase;
    border-radius: 50px;
    white-space: nowrap;
}

/* Clase reutilizable para iconos SVG inline */
.icon {
    display: inline-block;
    width: 1em;
    height: 1em;
    vertical-align: middle;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

/* 6. FOOTER */
.main-footer {
    background-color: var(--color-bg-subtle);
    padding: 60px 20px 30px 20px;
    margin-top: 80px;
    color: var(--color-text);
    font-size: 14px;
}

.footer-container {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 40px;
}

.footer-column { flex: 1; min-width: 200px; }
.footer-column h4 { font-size: 14px; color: var(--color-text-muted); text-transform: uppercase; margin-bottom: 20px; }
.footer-column ul { list-style: none; padding: 0; }
.footer-column ul li { margin-bottom: 10px; }
.footer-column ul li a { text-decoration: none; color: var(--color-text-body); }
.footer-column ul li a:hover { color: var(--color-primary); text-decoration: underline; }

/* Línea con icono en el footer de contacto */
.footer-contact-item {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 10px;
}

.footer-contact-item .icon {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

.footer-bottom {
    max-width: 1100px;
    margin: 40px auto 0 auto;
    padding-top: 20px;
    border-top: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    color: var(--color-text-muted);
    font-size: 12px;
}

.legal-links a { text-decoration: none; color: var(--color-text-muted); margin: 0 5px; }

/* 7. BOTÓN SCROLL TO TOP (creado por JavaScript) */
#scrollTopBtn {
    display: none;
    position: fixed;
    bottom: 30px;
    right: 30px;
    background-color: var(--color-primary);
    color: white;
    border: none;
    border-radius: 50%;
    width: 45px;
    height: 45px;
    font-size: 20px;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    transition: background-color 0.2s;
    z-index: 100;
}

#scrollTopBtn:hover { background-color: var(--color-primary-hover); }