body {
            font-family: 'Helvetica Neue', 'Arial', 'Hiragino Sans', 'Meiryo', sans-serif;
        }
        .hero {
            background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.6)), url('../images/header-background.jpg') no-repeat center center;
            background-size: cover;
            color: white;
            padding: 100px 20px;
            text-align: center;
        }
        .hero h1 {
            font-size: 2.8rem;
            font-weight: bold;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.7);
        }
        .hero p {
            font-size: 1.4rem;
            margin-top: 20px;
        }
        .section-title {
            text-align: center;
            margin-bottom: 50px;
            font-weight: bold;
            position: relative;
            padding-bottom: 15px; /* Added for underline */
        }
        .section-title::after { /* Added for underline */
            content: '';
            position: absolute;
            left: 50%;
            bottom: 0;
            transform: translateX(-50%);
            width: 60px;
            height: 3px;
            background-color: #0d6efd;
            border-radius: 3px;
        }
        .profile-section {
            background-color: #f8f9fa;
        }
        .profile-img {
            max-width: 200px; /* Control image size */
            height: auto; /* Maintain aspect ratio */
            border: 5px solid #fff;
            box-shadow: 0 4px 10px rgba(0,0,0,0.1);
            margin-bottom: 20px; /* Add space below image */
        }
        .card-icon {
            font-size: 3rem; /* Make icons larger */
            color: #0d6efd; /* Bootstrap primary blue */
            margin-bottom: 1rem; /* Add some space below */
        }
        .step-card { /* New style for flow/custom-lecture steps */
            background-color: #fff;
            border: 1px solid #e0e0e0;
            border-radius: 8px;
            padding: 20px;
            box-shadow: 0 4px 15px rgba(0,0,0,0.05);
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            height: 100%;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
        }
        .step-card:hover { /* New style for flow/custom-lecture steps */
            transform: translateY(-5px);
            box-shadow: 0 6px 20px rgba(0,0,0,0.1);
        }
        .step-number { /* New style for flow/custom-lecture steps */
            font-size: 2.5rem;
            font-weight: bold;
            color: #0d6efd;
            margin-bottom: 10px;
        }
        .arrow-right { /* New style for arrows */
            display: flex;
            align-items: center;
            justify-content: center;
            height: 100%;
            font-size: 2rem;
            color: #0d6efd;
        }
        @media (max-width: 767.98px) { /* New style for arrows */
            .arrow-right {
                transform: rotate(90deg);
                height: auto;
                margin: 20px 0;
            }
        }
        .custom-card-header { /* New style for custom card headers */
            background-color: #e9ecef;
            padding: 0.75rem 1.25rem;
            margin-bottom: 0;
            border-bottom: 1px solid rgba(0,0,0,.125);
            border-top-left-radius: calc(0.25rem - 1px);
            border-top-right-radius: calc(0.25rem - 1px);
        }
        footer {
            background-color: #343a40;
            color: white;
            padding: 30px 0;
            text-align: center;
        }