/* Core Page Layout Containers */
.site-header {
    width: 100%;
    max-width: 500px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
}

.site-main {
    width: 100%;
    max-width: 500px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.app-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    width: 100%;
}

/* Featured Spanning Element Rules */
.app-grid > *.is-featured {
    grid-column: span 2;
}

.site-footer {
    width: 100%;
    max-width: 500px;
    margin-top: 50px;
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 16px 20px;
    padding-top: 20px;
    border-top: 1px solid rgba(142, 142, 147, 0.15);
}

/* Calendar Layout Engine */
.site-main--wide {
    max-width: 1000px;
}

.calendar-container {
    width: 100%;
    background: var(--card-bg);
    padding: 24px;
    border-radius: var(--calendar-radius);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    transition: background-color var(--transition-speed);
}

[data-theme="dark"] .calendar-container {
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.5);
}

.calendar-desktop-view {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.calendar-mobile-view {
    display: none;
}

/* Wide Layout Responsive Breakpoint */
@media (max-width: 768px) {
    .calendar-desktop-view {
        display: none;
    }
    
    .calendar-mobile-view {
        display: flex;
        flex-direction: column;
        gap: 16px;
        text-align: center;
    }
}


/* Layout Mobile Adaptability Override */
@media (max-width: 400px) {
    .app-grid {
        grid-template-columns: 1fr;
    }
    .app-grid > *.is-featured {
        grid-column: span 1;
    }
}