* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    color: #333;
}
a {
    text-decoration: none;
}

#container {
    width: 1000px;
    margin: 20px auto;
    background-color: #fff;
    box-shadow: 0 0 10px rgba(0,0,0,0.1);
}
#top-header {
    background-color: #e6e6fa;
    padding: 10px;
    overflow: hidden;
    border-bottom: 2px solid #fff;
}
#top-header .marquee {
    white-space: nowrap;
    display: inline-block;
    animation: text-scroll 20s linear infinite;
}
#top-header .marquee a {
    color: #4a148c;
    margin: 0 30px;
    font-weight: bold;
}
@keyframes text-scroll {
    0% { transform: translateX(1000px); }
    100% { transform: translateX(-100%); }
}
#navigation {
    background-color: #dcedc8;
    padding: 15px 20px;
    border-bottom: 2px solid #fff;
}
#navigation ul {
    list-style: none;
    display: flex;
    gap: 25px;
}
#navigation ul li a {
    color: #2e7d32;
    font-weight: bold;
    font-size: 16px;
    text-transform: uppercase;
}
#navigation ul li a:hover {
    color: #1b5e20;
    text-decoration: underline;
}

#main-wrapper {
    display: flex;
}

#sidebar {
    width: 25%;
    background-color: #bbdefb;
    padding: 20px;
    border-right: 2px solid #fff;
}
#sidebar h3 {
    color: #1565c0;
    margin-bottom: 15px;
    border-bottom: 2px solid #64b5f6;
    padding-bottom: 5px;
}
#sidebar ul {
    list-style: none;
}
#sidebar ul li {
    padding: 10px 0;
    border-bottom: 1px dashed #64b5f6;
}
#sidebar ul li a {
    color: #0d47a1;
}
#sidebar ul li a:hover {
    color: #d32f2f;
}

#right-wrapper {
    width: 75%;
    display: flex;
    flex-direction: column;
}

#header {
    background-color: #ffcdd2;
    padding: 15px;
    display: flex;
    align-items: center;
    border-bottom: 2px solid #fff;
}
#header .logo-box {
    width: 20%;
}
#header .logo-box img {
    width: 100%;
    height: auto;
    border-radius: 50%;
    background-color: #fff;
}
#header .banner-box {
    width: 80%;
    padding-left: 20px;
}
#header .banner-box img {
    width: 100%;
    height: auto; /* Để ảnh tự co giãn chiều cao theo tỷ lệ chuẩn */
    border: 2px solid #ef5350;
}
#content-area {
    background-color: #e3f2fd;
    padding: 20px;
    flex-grow: 1;
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}
#content-area h2 {
    width: 100%;
    color: #1565c0;
    margin-bottom: 10px;
}
.content-item {
    width: calc(33.333% - 14px);
    background-color: #fff;
    border: 1px solid #90caf9;
    border-radius: 5px;
    padding: 10px;
    text-align: center;
}
.content-item img {
    width: 100%;
    height: 120px;
    object-fit: cover;
    margin-bottom: 10px;
    border-radius: 3px;
}
.content-item h4 {
    color: #d32f2f;
    font-size: 15px;
    margin-bottom: 5px;
}
.content-item p {
    font-size: 13px;
    color: #666;
    line-height: 1.4;
}

#footer {
    background-color: #d1c4e9;
    padding: 20px;
    text-align: center;
    border-top: 2px solid #fff;
}
#footer p span.student-info {
    font-weight: bold;
    color: #4a148c;
}