.flex {
    display: flex;
}

.flex-col {
    display: flex;
    flex-direction: column;
}

.items-center {
    align-items: center;
}

.justify-center {
    justify-content: center;
}

.justify-between {
    justify-content: space-between;
}

.gap-1 {
    gap: 4px;
}

.gap-2 {
    gap: 8px;
}

.gap-3 {
    gap: 12px;
}

.gap-4 {
    gap: 16px;
}

.p-1 {
    padding: 4px;
}

.p-2 {
    padding: 8px;
}

.p-3 {
    padding: 12px;
}

.p-4 {
    padding: 16px;
}

.m-1 {
    margin: 4px;
}

.m-2 {
    margin: 8px;
}

.m-3 {
    margin: 12px;
}

.m-4 {
    margin: 16px;
}

/* Responsive Layout */
@media (max-width: 600px) {
    #app {
        flex-direction: column-reverse;
        /* Bottom nav on mobile */
    }

    .nav-rail {
        width: 100%;
        height: 80px;
        flex-direction: row;
    }
}

@media (min-width: 601px) {
    #app {
        flex-direction: row;
        /* Side nav on desktop */
    }

    .nav-rail {
        width: 240px;
        /* Standard drawer width */
        height: 100%;
        flex-direction: column;
        align-items: flex-start;
        /* Align items to left */
        padding-top: 24px;
        border-right: 1px solid var(--md-sys-color-outline);
    }

    .nav-item {
        flex-direction: row;
        width: 100%;
        justify-content: flex-start;
        padding: 16px 24px;
        gap: 12px;
        border-radius: 0 24px 24px 0;
        /* Drawer item shape */
        margin-right: 12px;
    }

    .nav-icon {
        margin-bottom: 0;
    }

    #main-content {
        flex: 1;
        display: flex;
        justify-content: center;
        overflow-y: auto;
    }
}