:root {
    /* SOFT Theme Colors */
    --osteo-bg: #F5F7F8;
    --osteo-surface: #FFFFFF;
    --osteo-surface-dark: #EAECEE;
    --osteo-tone: #5DADE2;
    --osteo-tone-hover: #3498DB;
    --osteo-ink: #34495E;
    --osteo-ink-dark: #2C3E50;
    --osteo-ink-light: #7F8C8D;
    
    /* Preset B Gradient */
    --osteo-gradient: linear-gradient(135deg, #EBF5FB 0%, #D6EAF8 100%);
    
    /* Typography */
    --font-heading: 'Oswald', sans-serif;
    --font-body: 'Lato', sans-serif;
    
    /* Visuals - Soft radius, Deep shadow */
    --osteo-radius-val: 16px;
    --osteo-shadow-val: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

body {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.osteo-heading {
    font-family: var(--font-heading);
    text-transform: uppercase;
}

.osteo-radius {
    border-radius: var(--osteo-radius-val);
}

.osteo-shadow {
    box-shadow: var(--osteo-shadow-val);
}

/* Gallery Interactivity */
.osteo-slide {
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.4s ease-in-out, visibility 0.4s ease-in-out;
}

#pic-1:checked ~ .osteo-main-stage .osteo-slide-1,
#pic-2:checked ~ .osteo-main-stage .osteo-slide-2,
#pic-3:checked ~ .osteo-main-stage .osteo-slide-3,
#pic-4:checked ~ .osteo-main-stage .osteo-slide-4 {
    opacity: 1;
    visibility: visible;
}

/* Thumbnail Styling (Preset B) */
.osteo-thumb-lbl {
    border: 3px solid transparent;
    border-radius: var(--osteo-radius-val);
    transition: border-color 0.2s ease;
    overflow: hidden;
}

.osteo-thumb-lbl:hover {
    border-color: var(--osteo-surface-dark);
}

#pic-1:checked ~ .osteo-thumb-nav label[for="pic-1"],
#pic-2:checked ~ .osteo-thumb-nav label[for="pic-2"],
#pic-3:checked ~ .osteo-thumb-nav label[for="pic-3"],
#pic-4:checked ~ .osteo-thumb-nav label[for="pic-4"] {
    border-color: var(--osteo-tone);
}

/* CTA Hover */
.osteo-action-trigger {
    transition: all 0.3s ease;
}

.osteo-action-trigger:hover {
    background-color: var(--osteo-tone-hover) !important;
    box-shadow: 0 25px 30px -5px rgba(0, 0, 0, 0.15), 0 15px 15px -5px rgba(0, 0, 0, 0.08);
}