@charset "utf-8";
/* CSS Document */

/* Reset CSS cơ bản */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background-color: #f4f6f9;
}

/* Header & Logo */
header {
    background-color: #2c3e50;
    color: #fff;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 2rem;
    height: 70px;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.logo {
    font-size: 1.5rem;
    font-weight: bold;
    letter-spacing: 1px;
}

/* Navigation & Dropdown */
.nav-links {
    list-style: none;
    display: flex;
    align-items: center;
}

.nav-links li {
    position: relative;
}

.nav-links a {
    display: block;
    color: #fff;
    text-decoration: none;
    padding: 1.5rem 1.2rem;
    transition: background 0.3s;
}

.nav-links a:hover {
    background-color: #34495e;
}

/* Dropdown Menu */
.dropdown-content {
    display: none;
    position: absolute;
    background-color: #2c3e50;
    min-width: 160px;
    box-shadow: 0px 8px 16px rgba(0,0,0,0.2);
    list-style: none;
    top: 100%;
    left: 0;
}

.dropdown-content a {
    padding: 1rem;
    border-bottom: 1px solid #34495e;
}

.dropdown:hover .dropdown-content {
    display: block;
}

/* Banner */
.banner {
    background: linear-gradient(135deg, #3498db, #2c3e50);
    color: white;
    padding: 5rem 2rem;
    text-align: center;
}

.banner-text h1 {
    font-size: 2.5rem;
    margin-bottom: 1px;
}

.banner-text p {
    font-size: 1.2rem;
    opacity: 0.9;
}

/* Main Body Content */
main {
    flex: 1;
    padding: 3rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

.page-content {
    background: #fff;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    animation: fadeIn 0.5s ease-in-out;
}

/* Hiệu ứng xuất hiện nội dung */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Footer */
footer {
    background-color: #2c3e50;
    color: #bdc3c7;
    text-align: center;
    padding: 1.5rem;
    font-size: 0.9rem;
    margin-top: auto;
}