body {
    font-family: 'Arial', sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f9f9f9; /* Nền sáng nhẹ */
}

/* Header */
header {
    background-color: #000; /* Đen */
    padding: 20px;
    color: white;
    text-align: center;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    transition: background-color 0.3s ease; /* Hiệu ứng khi chuyển đổi nền */
}

nav a {
    text-decoration: none;
    color: white;
    margin: 0 15px;
    font-size: 1em;
    transition: color 0.3s ease-in-out; /* Mượt mà khi thay đổi màu */
}

nav a:hover {
    color: greenyellow; /* Màu xanh nhạt khi di chuột */
}

/* Welcome section */
.welcome-section {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    background-color: #fff; /* Trắng */
    border-bottom: 1px solid #ddd;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.welcome-text {
    font-size: 1.5em;
    font-weight: bold;
    color: #333; /* Xám đậm */
}

.profile-picture {
    width: 50px;
    height: 50px;
    background-color: #000; /* Đen */
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    color: #fff;
    font-size: 1.2em;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
    transition: transform 0.3s ease-in-out; /* Thêm hiệu ứng phóng to khi hover */
}

.profile-picture:hover {
    transform: scale(1.1); /* Phóng to nhẹ khi hover */
}

/* Weekly streak and progress */
.streak-progress {
    display: flex;
    justify-content: space-between;
    padding: 20px;
    background-color: #fff; /* Trắng */
    border-bottom: 1px solid #ddd;
    margin-bottom: 10px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.streak, .progress {
    display: flex;
    align-items: center;
}

.streak h3, .progress h3 {
    margin: 0;
    font-size: 1.2em;
    color: #333; /* Xám đậm */
}

.streak-icon, .progress-icon {
    margin-right: 15px;
    font-size: 2em;
    color: #000; /* Đen */
}

/* Continue learning section */
.courses-section {
    padding: 20px;
    background-color: #fff; /* Trắng */
    border-top: 1px solid #ddd;
}

.courses-section h2 {
    font-size: 1.4em;
    margin-bottom: 10px;
    color: #333; /* Xám đậm */
}

.course-list {
    display: flex;
    overflow-x: auto;
    padding: 10px 0;
}

.course-card {
    background-color: #fff; /* Trắng */
    border: 1px solid #ddd;
    border-radius: 5px;
    margin-right: 10px;
    padding: 10px;
    width: 250px;
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: transform 0.3s ease-in-out, box-shadow 0.3s ease-in-out;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.course-card:hover {
    transform: scale(1.1); /* Phóng to nhẹ khi di chuột */
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2); /* Tăng bóng đổ */
}

.course-card img {
    width: 100%;
    height: auto;
    border-radius: 5px;
    transition: transform 0.3s ease-in-out;
}

.course-card:hover img {
    transform: scale(1.05); /* Hình ảnh phóng to nhẹ khi hover */
}

.course-title {
    font-size: 1em;
    font-weight: bold;
    margin-top: 10px;
    color: #333; /* Xám đậm */
}

.course-lecture {
    font-size: 0.9em;
    color: #555; /* Xám nhạt */
}

.view-all {
    text-align: right;
    margin-top: 10px;
}

.view-all a {
    text-decoration: none;
    color: #000; /* Đen */
    font-size: 0.9em;
    font-weight: bold;
    transition: color 0.3s ease-in-out;
}

.view-all a:hover {
    color: #333; /* Xám đậm khi di chuột */
}

/* Responsive Design */
@media (max-width: 600px) {
    .course-list {
        flex-direction: column;
        align-items: center;
    }

    .course-card {
        margin-right: 0;
        margin-bottom: 10px;
        width: 100%; /* Full width on smaller screens */
    }

    .welcome-section img {
        width: 50px;
        height: 50px;
        border-radius: 50%;
    }
}

/* Certification section */
.certification-section {
    padding: 20px;
    background-color: #fff;
    margin: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}
.blue-link {
    color: blue;
    text-decoration: underline;
    font-size: 14px; /* Adjust this size to match your preferred size */
}

.blue-link:hover {
    text-decoration: underline; /* Keeps underline on hover */
}



.certification-section h2 {
    font-size: 1.4em;
    margin-bottom: 10px;
    color: #333;
}

.course-list {
    display: flex;
    gap: 20px;
    margin-bottom: 20px;
}

.course-card {
    background-color: #f9f9f9;
    padding: 15px;
    border-radius: 8px;
    text-align: center;
    width: 23%;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease-in-out, box-shadow 0.3s ease-in-out;
}

.course-card:hover {
    transform: scale(1.05); /* Phóng to nhẹ khi hover */
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2); /* Tăng bóng đổ */
}

.course-card img {
    width: 100%;
    height: auto;
    border-radius: 5px;
    margin-bottom: 10px;
}

.course-title {
    font-size: 1.1em;
    margin-bottom: 5px;
}

.course-lecture {
    font-size: 0.9em;
    color: #888;
}

/* Personalize section */
.personalize-section {
    margin-top: 20px;
    padding: 20px;
    background-color: #f9f9f9;
    border: 1px solid #ddd;
    text-align: center;
    border-radius: 10px;
}

.personalize-section h3 {
    font-size: 1.2em;
    margin-bottom: 10px;
    color: #333;
}

.personalize-section button {
    background-color: #f57c00;
    color: white;
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1em;
    transition: background-color 0.3s ease;
}

.personalize-section button:hover {
    background-color: #e66900; /* Mượt mà khi thay đổi màu */
}