/* Basic setup */
body {
    margin: 0;
    font-family: sans-serif;
    display: flex;
    flex-direction: column;
    height: 100vh;
}

/* Menu styling */
#main-menu {
    display: flex;
    justify-content: center;
    padding: 1rem;
    background-color: #ccc;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
    flex-shrink: 0;
}

#main-menu a {
    color: #002D45FD;
    text-decoration: none; 
    padding: 0.5rem 1.5rem;
    margin: 0 0.5rem;
    border-radius: 5px;
    transition: background-color 0.3s, color 0.3s;
}

#main-menu a:hover, #main-menu a.active {
    background-color: #002D45FD;
    color: #ffffff;
}

/* Content container and iframe */
#content-container {
    flex-grow: 1;
    overflow: hidden; /* Important for iframe to not cause double scrollbars */
    position: relative;
}

#content-frame {
    width: 100%;
    height: 100%;
    border: none;
    opacity: 1;
    transition: opacity 0.5s ease-in-out;
}

#content-frame.fading {
    opacity: 0;
}

/* Loading screen */
#loading-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #f5f5f5 0%, #e8e8e8 50%, #f0f0f0 100%);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10;
    transition: opacity 0.3s ease-in-out;
}

#loading-screen.hidden {
    opacity: 0;
    pointer-events: none;
}

/* Loading spinner */
.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid #d0d0d0;
    border-top: 4px solid #666666;
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}