/* Global Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Open Sans', sans-serif;
}

body {
    line-height: 1.6;
    background-color: #f4f4f4;
    color: #333;
}

.container {
    width: 85%;
    margin: auto;
    max-width: 1200px;
}

/* Header Styles */
header {
    background: linear-gradient(to right, rgb(26, 115, 232), rgb(197 223 255));
    color: white;
    padding: 20px 0;
    text-align: center;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    font-weight: 700;
}

header p.subtitle {
    font-size: 1.2em;
    margin-bottom: 20px;
}

header a.btn {
    background: #f7941d;
    color: white;
    padding: 10px 20px;
    border-radius: 50px;
    text-transform: uppercase;
    text-decoration: none;
    font-weight: bold;
    transition: background 0.3s;
}

header a.btn:hover {
    background: #d37715;
}

/* Navigation Bar */
nav {
    background-color: #333;
    position: sticky;
    top: 0;
    width: 100%;
    z-index: 1000;
    padding: 10px 0;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

nav ul {
    list-style: none;
    text-align: center;
}

nav ul li {
    display: inline;
    margin: 0 15px;
}

nav ul li a {
    color: #fff;
    text-decoration: none;
    font-size: 1.1em;
}

nav ul li a:hover {
    text-decoration: underline;
}

/* Feature Section */
#gioi-thieu {
    background-color: #fff;
    padding: 50px 0;
    text-align: center;
}

#gioi-thieu h2 {
    font-size: 2em;
    margin-bottom: 20px;
}

#gioi-thieu p {
    font-size: 1.2em;
    margin-bottom: 30px;
}

#gioi-thieu ul.features {
    list-style: none;
    padding: 0;
}

#gioi-thieu ul.features li {
    margin: 15px 0;
    font-size: 1.1em;
    display: flex;
    align-items: center;
    justify-content: center;
}

#gioi-thieu ul.features li::before {
    content: "✔";
    color: #f7941d;
    font-size: 1.5em;
    margin-right: 10px;
}

/* Language Cards */
#ngon-ngu {
    background-color: #fafafa;
    padding: 50px 0;
    text-align: center;
}

.language-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin-top: 30px;
}

.language-list li {
    background-color: #fff;
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.language-list li:hover {
    transform: translateY(-10px);
    box-shadow: 0 8px 12px rgba(0, 0, 0, 0.2);
}

.flag-btn {
    display: block;
    font-size: 1.2em;
    font-weight: bold;
    text-decoration: none;
    color: #333;
    padding: 10px 0;
}

/* Call-to-Action Section */
#call-to-action {
    background-color: #2575fc;
    color: white;
    text-align: center;
    padding: 50px 0;
}

#call-to-action h2 {
    font-size: 2.5em;
    margin-bottom: 20px;
}

#call-to-action p.price {
    font-size: 1.5em;
    margin-bottom: 30px;
}

#call-to-action a.btn {
    background: #f7941d;
    color: white;
    padding: 15px 30px;
    border-radius: 50px;
    font-size: 1.1em;
    text-transform: uppercase;
    text-decoration: none;
    font-weight: bold;
    transition: background 0.3s;
}

#call-to-action a.btn:hover {
    background: #d37715;
}

/* Popup */
.popup {
    display: none;
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 80%;
    max-width: 640px;
    background-color: white;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    padding: 20px;
    z-index: 1001;
}

.popup .close {
    position: absolute;
    top: 10px;
    right: 20px;
    font-size: 1.5em;
    cursor: pointer;
}

/* Footer */
footer {
    background-color: #333;
    color: #fff;
    padding: 20px 0;
    text-align: center;
}

footer h3 {
    font-size: 1.8em;
    margin-bottom: 10px;
}

footer p {
    font-size: 1.1em;
}

footer ul.social-media {
    list-style: none;
    padding: 0;
    margin-top: 10px;
}

footer ul.social-media li {
    display: inline-block;
    margin: 0 10px;
}

footer ul.social-media li a {
    color: white;
    font-size: 1.5em;
    text-decoration: none;
}

footer ul.social-media li a:hover {
    color: #f7941d;
}
/* Button Styles */
.btn {
    display: inline-block;
    padding: 10px 20px;
    background-color: #f7941d; /* Primary button color */
    color: white;
    font-size: 1em;
    font-weight: bold;
    text-transform: uppercase;
    text-decoration: none;
    border-radius: 50px; /* Rounded corners */
    transition: background-color 0.3s ease, transform 0.3s ease;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1); /* Light shadow for 3D effect */
}

.btn:hover {
    background-color: #d37715; /* Darker orange on hover */
    transform: translateY(-3px); /* Slight lift effect on hover */
    box-shadow: 0 6px 10px rgba(0, 0, 0, 0.15);
}

.btn-secondary {
    background-color: #2575fc; /* Secondary button color (blue) */
}

.btn-secondary:hover {
    background-color: #1a5ed1; /* Darker blue on hover */
}

/* Disabled Button */
.btn:disabled,
.btn[disabled] {
    background-color: #ccc;
    color: #666;
    cursor: not-allowed;
    box-shadow: none;
}
/* Reset list styles */
ul {
    list-style: none; /* Xóa dấu chấm trước các phần tử <li> */
    padding-left: 0; /* Xóa khoảng cách bên trái */
}

/* List items styling */
ul li {
    margin-bottom: 10px; /* Khoảng cách giữa các mục để dễ nhìn */
    font-size: 1.1em; /* Tăng kích thước chữ để dễ đọc */
    padding-left: 20px; /* Tạo khoảng cách bên trái để canh chỉnh gọn */
    position: relative; /* Để sử dụng icon thay thế dấu chấm */
}

/* Custom bullet points (optional) */
ul li::before {
    font-size: 1.5em; /* Kích thước chấm tròn */
    position: absolute;
    left: 0;
    top: 0;
}