:root {
        --primary: #3E55AA;
        --primary-light: #4F6EC7;
        --primary-ultralight: #EEF2FF;
        --secondary: #FF6B6B;
        --accent: #4ECDC4;
        --dark: #1E293B;
        --light: #F8FAFC;
        --gray: #64748B;
        --gray-light: #E2E8F0;
        --gray-ultralight: #F1F5F9;
        --success: #10B981;
    }
    
    body {
        font-family: 'Poppins', sans-serif;
        background-color: #F9FAFB;
        color: var(--dark);
        margin: 0;
        padding: 0;
        line-height: 1.6;
    }

    /* Navigation */
    .nav-container {
        background: linear-gradient(120deg, var(--primary), var(--primary-light));
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
        backdrop-filter: blur(10px);
    }

    /* Sidebar - Modern Professional Style */
    .sidebar {
        background: linear-gradient(180deg, #FFFFFF 0%, #FCFDFF 100%);
        box-shadow: 4px 0 20px rgba(0, 0, 0, 0.03);
        border-right: 1px solid var(--gray-light);
        transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    
   .sidebar-header {
    /* border-bottom: 1px solid var(--gray-light); */ /* ❌ remove this */
    padding: 1.1rem 1.25rem;
}

    
    
    
   .sidebar-item {
    display: flex;
    align-items: center;
    padding: 0.6rem 1rem;
    border-radius: 0.5rem;
    color: var(--gray);
    transition: color 0.2s ease; /* only color transition */
    font-weight: 500;
     margin: 0.15rem 0.5rem;
    position: relative;
    font-size: 0.85rem;
    text-decoration: none; /* ensure no underline */
    background-color: transparent; /* remove hover background */
}
.sidebar-item:hover {
    color: #1F2937;            /* dark gray instead of black */
    background-color: #F8FAFC; /* ultra light gray hover background */
    text-decoration: none;      /* no underline */
}


    
    .sidebar-item.active {
        background-color: var(--primary-ultralight);
        color: var(--primary);
        font-weight: 600;
    }
    
    .sidebar-item.active::before {
        content: '';
        position: absolute;
        left: 0;
        top: 50%;
        transform: translateY(-50%);
        height: 50%;
        width: 3px;
        background-color: var(--primary);
        border-radius: 0 2px 2px 0;
    }
    
   .sidebar-bullet {
    display: inline-block;
    width: 5px;              /* slightly bigger for visibility */
    height: 5px;
    background-color: #9CA3AF; /* modern gray, subtle but visible */
    border-radius: 50%;        /* perfectly round */
    margin-right: 0.75rem;
    flex-shrink: 0;
    transition: background-color 0.2s ease;
}

/* Optional: change bullet color slightly on hover */
.sidebar-item:hover .sidebar-bullet {
    background-color: #6B7280; /* slightly darker gray */
}

    .sidebar-badge {
        margin-left: auto;
        background-color: #EFF7FE;
        color: #3E55AA;
        font-size: 0.7rem;
        padding: 0.15rem 0.5rem;
        border-radius: 0.75rem;
        font-weight: 600;
        min-width: 1.4rem;
        text-align: center;
        box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
    }
    
    .sidebar-section {
        display: flex;
        align-items: center;
        padding: 0.7rem 1.25rem 0.5rem;
        font-size: 0.75rem;
        text-transform: uppercase;
        letter-spacing: 0.05em;
        color: var(--gray);
        font-weight: 600;
    }
    
    .section-icon {
        margin-right: 0.5rem;
        color: var(--primary);
        font-size: 0.8rem;
    }
    
    .sidebar-divider {
        height: 1px;
        background-color: var(--gray-light);
        margin: 0.4rem 0.75rem;
    }

  .module-section {
    background: #fff;
    border-radius: 16px;   /* big round outer frame */
    padding: 1.5rem;       /* balanced spacing */
    margin-bottom: 2rem;   /* consistent gap */
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    border: 1px solid var(--gray-light);
}

.box-section {
    background: #fff;
    border-radius: 10px;   /* smaller than parent */
    padding: 2rem;         /* more generous since it holds real content */
    margin-bottom: 2rem;
    border: 1px solid var(--gray-light);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

    .module-header {
        margin-bottom: 1.25rem;
    }
    
    .module-title {
        font-size: 1.25rem;
        font-weight: 600;
        color: var(--dark);
        margin-bottom: 0.5rem;
    }
    
    .module-description {
        color: var(--gray);
        font-size: 0.9rem;
        line-height: 1.5;
    }
    
    .lessons-label {
        font-size: 0.75rem;
        text-transform: uppercase;
        font-weight: 600;
        color: var(--gray);
        letter-spacing: 0.05em;
        margin-bottom: 1rem;
        display: block;
    }
    
    .lesson-item {
        display: flex;
        align-items: center;
        padding: 0.9rem 1rem;
        border-radius: 8px;
        margin-bottom: 0.5rem;
        transition: background-color 0.2s ease;
        border: 1px solid transparent;
    }
    
    .lesson-item:hover {
        background-color: var(--primary-ultralight);
        border-color: var(--gray-light);
    }
    
    .lesson-number {
        width: 28px;
        height: 28px;
        border-radius: 6px;
        background-color: var(--primary-ultralight);
        color: var(--primary);
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: 600;
        font-size: 0.8rem;
        margin-right: 1rem;
        flex-shrink: 0;
    }
    
    .lesson-content {
        flex-grow: 1;
        display: flex;
        align-items: center;
        justify-content: space-between;
    }
    
    .lesson-title {
        font-weight: 500;
        color: var(--dark);
        font-size: 0.95rem;
    }
    
    .lesson-meta {
        display: flex;
        align-items: center;
        gap: 1rem;
    }
    
    .lesson-duration {
        color: var(--gray);
        font-size: 0.85rem;
        white-space: nowrap;
    }
    
    .lesson-badge {
        background-color: var(--success);
        color: white;
        padding: 0.2rem 0.6rem;
        border-radius: 4px;
        font-size: 0.75rem;
        font-weight: 500;
        white-space: nowrap;
    }
    
    .lesson-badge.free {
        background-color: var(--success);
    }

   .sidebar-item.bg-blue-100 {
    border-left: 4px solid #3C52A6; /* your theme color */
    padding-left: 0.75rem;
}



    /* Mobile sidebar */
    @media (max-width: 768px) {
        .sidebar-mobile-hidden {
            transform: translateX(-100%);
        }
        
        .sidebar {
            width: 280px;
        }
        
        .lesson-content {
            flex-direction: column;
            align-items: flex-start;
            gap: 0.5rem;
        }
        
        .lesson-meta {
            width: 100%;
            justify-content: space-between;
        }
    }
    @media (min-width: 768px) {
    #sidebar-backdrop {
        display: none !important;
    }
}