body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
}
.container {
    width: 80%;
    margin: auto;
    overflow: hidden;
}
header {
    background: linear-gradient(to right, #333, #77aaff);
    color: #fff;
    padding-top: 30px;
    min-height: 70px;
    border-bottom: #77aaff 3px solid;
}
header a {
    color: #fff;
    text-decoration: none;
    text-transform: uppercase;
    font-size: 16px;
}
header ul {
    padding: 0;
    list-style: none;
}
header li {
    float: left;
    display: inline;
    padding: 0 20px 0 20px;
}
header #branding {
    float: left;
}
header #branding h1 {
    margin: 0;
}
header nav {
    float: right;
    margin-top: 10px;
}
.profile {
    display: flex;
    justify-content: space-between;
    margin-top: 20px;
}
.profile .info, .profile .achievements {
    background: #fff;
    padding: 20px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    width: 48%;
}
.profile .info h2, .profile .achievements h2 {
    border-bottom: 2px solid #77aaff;
    padding-bottom: 10px;
}
.profile .info p, .profile .achievements ul {
    margin: 10px 0;
}
.profile .achievements ul {
    list-style: none;
    padding: 0;
}
.profile .achievements ul li {
    background: #77aaff;
    color: #fff;
    margin-bottom: 10px;
    padding: 10px;
    border-radius: 5px;
    transition: background 0.3s;
}
.profile .achievements ul li:hover {
    background: #0056b3;
}/* Reset và Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #4a6bff;
    --secondary-color: #ff8a00;
    --dark-color: #333;
    --light-color: #f4f4f4;
    --text-color: #555;
    --border-radius: 8px;
    --box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #f9f9f9;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Typography */
h1, h2, h3, h4 {
    color: var(--dark-color);
    margin-bottom: 15px;
}

h1 {
    font-size: 2.5rem;
}

h2 {
    font-size: 2rem;
}

h3 {
    font-size: 1.5rem;
}

p {
    margin-bottom: 15px;
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: var(--transition);
}

a:hover {
    color: var(--secondary-color);
}

.highlight {
    color: var(--primary-color);
}

.btn {
    display: inline-block;
    background-color: var(--primary-color);
    color: #fff;
    padding: 12px 25px;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 600;
    text-align: center;
}

.btn:hover {
    background-color: var(--secondary-color);
    color: #fff;
    transform: translateY(-3px);
    box-shadow: var(--box-shadow);
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
    position: relative;
    padding-bottom: 15px;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background-color: var(--primary-color);
    border-radius: 2px;
}

section {
    padding: 80px 0;
}

section:nth-child(even) {
    background-color: #fff;
}

/* Header & Navigation */
header {
    background-color: #fff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 0;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
}

.menu {
    display: flex;
    list-style: none;
}

.menu li {
    margin-left: 30px;
}

.menu li a {
    color: var(--dark-color);
    font-weight: 500;
    padding: 8px 0;
    position: relative;
}

.menu li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary-color);
    transition: var(--transition);
}

.menu li a:hover::after {
    width: 100%;
}

.menu-toggle {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
}

/* Hero Section */
#hero {
    height: 100vh;
    display: flex;
    align-items: center;
    text-align: center;
    background: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), url('/api/placeholder/1920/1080') center/cover no-repeat;
    color: #fff;
    margin-top: -80px;
}

#hero h1 {
    font-size: 3.5rem;
    margin-bottom: 20px;
    color: #fff;
}

#hero p {
    font-size: 1.5rem;
    margin-bottom: 30px;
}

/* About Section */
.about-content {
    display: flex;
    align-items: flex-start;
    gap: 50px;
}

.about-image {
    flex: 1;
}

.about-image img {
    width: 100%;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.about-text {
    flex: 2;
}

.personal-info {
    margin-top: 20px;
    margin-bottom: 30px;
}

.info-item {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
}

.info-item i {
    width: 30px;
    color: var(--primary-color);
    margin-right: 10px;
}

.skills h3 {
    margin-bottom: 20px;
}

.skill-item {
    margin-bottom: 15px;
}

.skill-item span {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

.skill-bar {
    height: 10px;
    background-color: #ddd;
    border-radius: 5px;
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    background-color: var(--primary-color);
    border-radius: 5px;
}

/* Achievements Section */
.achievement-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.achievement-card {
    background-color: #fff;
    padding: 30px;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    text-align: center;
    transition: var(--transition);
}

.achievement-card:hover {
    transform: translateY(-10px);
}

.achievement-icon {
    width: 70px;
    height: 70px;
    background-color: var(--light-color);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    margin: 0 auto 20px;
}

.achievement-icon i {
    font-size: 30px;
    color: var(--primary-color);
}

/* Courses Section */
.course-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.course-card {
    background-color: #fff;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.course-card:hover {
    transform: translateY(-10px);
}

.course-image img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.course-content {
    padding: 20px;
}

/* Contact Section */
.contact-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 50px;
}

.contact-info {
    background-color: var(--primary-color);
    color: #fff;
    padding: 30px;
    border-radius: var(--border-radius);
}

.contact-info h3 {
    color: #fff;
    margin-bottom: 20px;
}

.contact-item {
    display: flex;
    align-items: center;
    margin-bottom: 15px;
}

.contact-item i {
    margin-right: 15px;
    font-size: 18px;
}

.social-links {
    margin-top: 30px;
    display: flex;
    gap: 15px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: rgba(255, 255, 255, 0.2);
    color: #fff;
    border-radius: 50%;
    transition: var(--transition);
}

.social-links a:hover {
    background-color: #fff;
    color: var(--primary-color);
}

.contact-form {
    padding: 30px;
    background-color: #fff;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.form-group {
    margin-bottom: 20px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #ddd;
    border-radius: var(--border-radius);
    font-family: inherit;
    font-size: 1rem;
    transition: var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
}

.form-group textarea {
    height: 150px;
    resize: vertical;
}

/* Footer */
footer {
    background-color: var(--dark-color);
    color: #fff;
    text-align: center;
    padding: 30px 0;
}

/* Responsive Design */
@media (max-width: 992px) {
    .about-content {
        flex-direction: column;
    }
    
    .about-image {
        margin-bottom: 30px;
    }
}

@media (max-width: 768px) {
    .menu {
        position: fixed;
        top: 80px;
        left: -100%;
        width: 100%;
        background-color: #fff;
        flex-direction: column;
        text-align: center;
        transition: var(--transition);
        box-shadow: 0 10px 15px rgba(0, 0, 0, 0.1);
        padding: 20px 0;
    }
    
    .menu.active {
        left: 0;
    }
    
    .menu li {
        margin: 15px 0;
    }
    
    .menu-toggle {
        display: block;
    }
    
    #hero h1 {
        font-size: 2.5rem;
    }
    
    #hero p {
        font-size: 1.2rem;
    }
}