:root {
    --bg-color: #f9fafb;
    --text-color: #2d3748;
    --nav-bg: #ffffff;
    --button-bg: #3b82f6;
    --button-hover-bg: #2563eb;
    --card-bg: #ffffff;
    --shadow-color: rgba(0, 0, 0, 0.1);
}

body.dark-mode {
    --bg-color: #111827;
    --text-color: #d1d5db;
    --nav-bg: #1f2937;
    --button-bg: #60a5fa;
    --button-hover-bg: #3b82f6;
    --card-bg: #1f2937;
    --shadow-color: rgba(0, 0, 0, 0.3);
}

body {
    margin: 0;
    font-family: Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    transition: background-color 0.3s, color 0.3s;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    background-color: var(--nav-bg);
    box-shadow: 0 2px 4px var(--shadow-color);
    position: sticky;
    top: 0;
}

nav .logo {
    font-size: 1.5rem;
    font-weight: bold;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
    margin: 0;
}

nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
}

nav ul li a:hover {
    color: var(--button-bg);
}

.nav-buttons {
    display: flex;
    gap: 1rem;
}

nav button#language-toggle,
nav button#theme-toggle {
    padding: 0.5rem 1rem;
    background-color: var(--button-bg);
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s;
}

nav button#theme-toggle {
    padding: 0.5rem;
    font-size: 1rem;
}

nav button#language-toggle:hover,
nav button#theme-toggle:hover {
    background-color: var(--button-hover-bg);
}

.hero {
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    background-color: var(--bg-color);
    padding: 0 2rem;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.hero p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.cta-button {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background-color: var(--button-bg);
    color: #fff;
    text-decoration: none;
    border-radius: 8px;
    transition: background-color 0.3s;
}

.cta-button:hover {
    background-color: var(--button-hover-bg);
}

.section {
    padding: 4rem 2rem;
    text-align: center;
}

.section h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.portfolio-item {
    background-color: var(--card-bg);
    padding: 1.5rem;
    border-radius: 8px;
    box-shadow: 0 2px 4px var(--shadow-color);
    transition: background-color 0.3s;
}

.form-container {
    max-width: 500px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.form-container input,
.form-container textarea {
    padding: 0.75rem;
    border: 1px solid #ccc;
    border-radius: 8px;
    background-color: var(--card-bg);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
}

.form-container button {
    padding: 0.75rem;
    background-color: var(--button-bg);
    color: #fff;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.form-container button:hover {
    background-color: var(--button-hover-bg);
}

#form-message {
    margin-top: 1rem;
    font-size: 1rem;
    text-align: center;
}

#form-message.success {
    color: #2ecc71;
}

#form-message.error {
    color: #e74c3c;
}

footer {
    text-align: center;
    padding: 1.5rem;
    background-color: var(--bg-color);
    transition: background-color 0.3s;
}

.social-links {
    margin-top: 1rem;
    display: flex;
    justify-content: center;
    gap: 1.5rem;
}

.social-icon {
    font-size: 1.5rem;
    color: var(--text-color);
    text-decoration: none;
    transition: color 0.3s;
}

.social-icon:hover {
    color: var(--button-bg);
}

.social-icon.linkedin:hover {
    color: #0a66c2;
}

.social-icon.twitter:hover {
    color: #000000;
}

.social-icon.github:hover {
    color: #181717;
}

.social-icon.instagram:hover {
    color: #e1306c;
}