:root {
    --bg-color: #f8f8f8;
    --text-color: #333;
    --header-bg: #fff;
    --nav-link-color: #555;
    --nav-link-hover: #007bff;
    --section-bg: #fff;
    --card-bg: #fff;
    --border-color: #ccc;
    --footer-bg: #333;
    --footer-text: #fff;
}

[data-theme="dark"] {
    --bg-color: #1a1a1a;
    --text-color: #f0f0f0;
    --header-bg: #2d2d2d;
    --nav-link-color: #ccc;
    --nav-link-hover: #3391ff;
    --section-bg: #1a1a1a;
    --card-bg: #2d2d2d;
    --border-color: #444;
    --footer-bg: #000;
    --footer-text: #ccc;
}

/* General Styles */
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Header and Navigation */
header {
    position: sticky;
    top: 0;
    background-color: var(--header-bg);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    z-index: 1000;
    transition: background-color 0.3s ease;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
}

.logo a {
    font-size: 1.5rem;
    font-weight: bold;
    text-decoration: none;
    color: var(--text-color);
}

nav ul {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
    align-items: center;
}

nav ul li {
    margin-left: 2rem;
}

nav ul li a {
    text-decoration: none;
    color: var(--nav-link-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

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

/* Theme Toggle Button */
.theme-toggle-btn {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--text-color);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.9rem;
    margin-left: 2rem;
    transition: all 0.3s ease;
}

.theme-toggle-btn:hover {
    background-color: var(--nav-link-hover);
    color: #fff;
    border-color: var(--nav-link-hover);
}

/* Hero Section */
.hero {
    background: url('https://via.placeholder.com/1920x1080') no-repeat center center/cover;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    color: #fff;
}

.hero-content {
    max-width: 800px;
    padding: 2rem;
    background-color: rgba(0, 0, 0, 0.5);
    border-radius: 10px;
}

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

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

.cta-button {
    display: inline-block;
    background-color: #007bff;
    color: #fff;
    padding: 0.8rem 1.5rem;
    text-decoration: none;
    border-radius: 5px;
    font-weight: bold;
    transition: background-color 0.3s ease;
}

.cta-button:hover {
    background-color: #0056b3;
}

/* Sections */
section {
    padding: 4rem 2rem;
}

section h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
}

/* Services Section */
.service-items {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.service-item {
    text-align: center;
}

.service-item img {
    border-radius: 50%;
    margin-bottom: 1rem;
}

.service-item h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

/* Portfolio Section */
.portfolio-items {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.portfolio-item {
    position: relative;
    overflow: hidden;
    border-radius: 10px;
}

.portfolio-item img {
    width: 100%;
    display: block;
    transition: transform 0.3s ease;
}

.portfolio-item:hover img {
    transform: scale(1.1);
}

.portfolio-caption {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background-color: rgba(0, 0, 0, 0.7);
    color: #fff;
    padding: 1rem;
    text-align: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.portfolio-item:hover .portfolio-caption {
    opacity: 1;
}

/* About Section */
#about {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

/* Contact Section */
#contact form {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

#contact input,
#contact textarea {
    padding: 0.8rem;
    border: 1px solid #ccc;
    border-radius: 5px;
}

#contact button {
    background-color: #007bff;
    color: #fff;
    padding: 0.8rem;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    transition: background-color 0.3s ease;
}

#contact button:hover {
    background-color: #0056b3;
}

.contact-info {
    text-align: center;
    margin-top: 2rem;
}

/* Footer */
footer {
    text-align: center;
    padding: 2rem;
    background-color: #333;
    color: #fff;
}