:root {
    --background-light: #f4f4f4;
    --background-dark: #1e1e1e;
    --text-light: #333;
    --text-dark: #f4f4f4;
    --primary-color: #0056b3;
    --secondary-color: #003d80;
    --accent-color: #ffcc00;
    --contact-color: #000; /* Contact link color */
    --footer-bg-light: #0056b3;
    --footer-bg-dark: #0d3d6d;
}

/* Common Styles */
body {
    font-family: 'Roboto', sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--background-light);
    color: var(--text-light);
    transition: background-color 0.3s, color 0.3s;
}

header {
    background-color: var(--primary-color);
    color: white;
    padding: 60px 20px;
    text-align: center;
    transition: background-color 0.3s;
}

header h1 {
    margin: 0;
    font-size: 3em;
    font-weight: bold;
}

header p {
    margin: 5px 0;
    font-size: 1.2em;
}

.contact-link {
    color: var(--contact-color);
    font-weight: bold;
}

.container {
    width: 80%;
    margin: 20px auto;
    padding-bottom: 50px;
}

section {
    margin: 40px 0;
    padding: 40px;
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transition: transform 0.3s ease;
}

section:hover {
    transform: translateY(-10px);
}

h2 {
    color: var(--secondary-color);
    font-size: 2em;
    margin-bottom: 20px;
    border-bottom: 3px solid var(--accent-color);
    padding-bottom: 10px;
    font-weight: 700;
    display: flex;
    align-items: center;
}

h2 i {
    margin-right: 10px;
}

.education-section {
    background: linear-gradient(to right, #f0f0f0, #e0e0e0);
}

.education-timeline {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.timeline-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

.experience-grid, .experience-item {
    display: grid;
    gap: 20px;
}

.experience-item {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.experience-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.project-link {
    color: var(--secondary-color);
    font-weight: bold;
    text-decoration: underline;
}

footer {
    text-align: center;
    padding: 30px 20px;
    background-color: var(--footer-bg-light);
    color: white;
    font-size: 1em;
    transition: background-color 0.3s;
}

footer i {
    color: var(--accent-color);
    margin-left: 5px;
}

/* Dark mode */
[data-theme="dark"] {
    --background-light: #1e1e1e;
    --text-light: #f4f4f4;
    --footer-bg-light: #0d3d6d;
    --primary-color: #0077cc;
    --secondary-color: #005fa3;
    --accent-color: #ffcc00;
}

[data-theme="dark"] body {
    background-color: var(--background-dark);
    color: var(--text-dark);
}

[data-theme="dark"] section {
    background-color: #2a2a2a;
    color: var(--text-dark);
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.3);
}

[data-theme="dark"] header {
    background-color: var(--primary-color);
    color: white;
}

[data-theme="dark"] footer {
    background-color: var(--footer-bg-dark);
}

/* Dark mode toggle button */
.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5em;
    cursor: pointer;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
    transition: background-color 0.3s, box-shadow 0.3s;
}

.theme-toggle:hover {
    background-color: var(--secondary-color);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.3);
}

.theme-toggle i {
    transition: transform 0.3s;
}

[data-theme="dark"] .theme-toggle {
    background-color: var(--accent-color);
}

[data-theme="dark"] .theme-toggle i {
    transform: rotate(180deg);
}

/* Media Queries */
@media (max-width: 768px) {
    .container {
        width: 90%;
    }

    header h1 {
        font-size: 2.5em;
    }

    section {
        padding: 30px 20px;
    }