/* Reset default styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Roboto', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #f5f7fa;
}

.container {
    width: 85%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
header {
    background: linear-gradient(135deg, #1a3c6e, #2c5b9e);
    color: #fff;
    text-align: center;
    padding: 3rem 0;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

header h1 {
    font-size: 2.8rem;
    font-weight: 700;
}

header p {
    font-size: 1.3rem;
    margin-top: 0.5rem;
    opacity: 0.9;
}

/* Navigation */
nav {
    background: #2c3e50;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
}

.nav-toggle {
    display: none;
    font-size: 1.8rem;
    color: #fff;
    cursor: pointer;
    padding: 1rem;
}

.nav-menu {
    list-style: none;
    display: flex;
    justify-content: center;
}

.nav-menu li {
    margin: 0 1.5rem;
    position: relative;
}

.nav-menu li a {
    color: #fff;
    text-decoration: none;
    padding: 1rem;
    font-size: 1.1rem;
    font-weight: 500;
    transition: color 0.3s ease, background 0.3s ease;
}

.nav-menu li a:hover {
    color: #a3bffa;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 5px;
}

.dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    background: #34495e;
    list-style: none;
    min-width: 200px;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
    border-radius: 5px;
}

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

.dropdown-menu li a {
    padding: 0.75rem 1rem;
    display: block;
}

.dropdown-menu li a:hover {
    background: #2c3e50;
}

/* Sections */
section {
    padding: 4rem 0;
    background: #fff;
    margin: 1rem 0;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

section h2 {
    font-size: 2.2rem;
    margin-bottom: 1.5rem;
    color: #1a3c6e;
    border-bottom: 2px solid #a3bffa;
    padding-bottom: 0.5rem;
}

section h3 {
    font-size: 1.6rem;
    margin: 1.5rem 0 0.75rem;
    color: #2c5b9e;
}

section p, section ul, section ol {
    margin-bottom: 1.5rem;
}

section ul, section ol {
    padding-left: 2rem;
}

section ul li, section ol li {
    margin-bottom: 0.75rem;
}

/* PhD Advertisement */
.phd-ad {
    background: #e9f0ff;
    padding: 1.5rem;
    border-radius: 8px;
    margin-top: 2rem;
    text-align: center;
}

.phd-ad h3 {
    color: #1a3c6e;
    margin-bottom: 1rem;
}

.btn {
    display: inline-block;
    background: #2c5b9e;
    color: #fff;
    padding: 0.75rem 1.5rem;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 500;
    transition: background 0.3s ease;
}

.btn:hover {
    background: #1a3c6e;
}

/* Contact Form */
form {
    display: flex;
    flex-direction: column;
    max-width: 600px;
    margin-top: 1.5rem;
}

form label {
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #2c3e50;
}

form input, form textarea {
    margin-bottom: 1.5rem;
    padding: 0.75rem;
    border: 1px solid #ccc;
    border-radius: 5px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

form input:focus, form textarea:focus {
    border-color: #2c5b9e;
    outline: none;
}

form textarea {
    height: 150px;
    resize: vertical;
}

form button {
    background: #2c5b9e;
    color: #fff;
    border: none;
    padding: 0.75rem 1.5rem;
    cursor: pointer;
    font-size: 1.1rem;
    border-radius: 5px;
    transition: background 0.3s ease;
}

form button:hover {
    background: #1a3c6e;
}

.success {
    color: #28a745;
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.error {
    color: #dc3545;
    margin-bottom: 1.5rem;
    font-weight: 500;
}

/* Footer */
footer {
    background: #2c3e50;
    color: #fff;
    text-align: center;
    padding: 1.5rem 0;
    margin-top: 2rem;
}

footer p {
    font-size: 1rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-toggle {
        display: block;
    }

    .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 60px;
        left: 0;
        width: 100%;
        background: #2c3e50;
        padding: 1rem 0;
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-menu li {
        margin: 0.5rem 0;
        text-align: center;
    }

    .dropdown-menu {
        position: static;
        background: #34495e;
        width: 100%;
        box-shadow: none;
    }

    .dropdown:hover .dropdown-menu {
        display: none;
    }

    .dropdown.active .dropdown-menu {
        display: block;
    }

    header h1 {
        font-size: 2rem;
    }

    header p {
        font-size: 1.1rem;
    }

    .container {
        width: 90%;
    }
}