:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --light-bg: #f4f4f4;
    --light-text: #333;
    --dark-bg: #1a1a1a;
    --dark-text: #f4f4f4;
    --card-bg-light: #ffffff;
    --card-bg-dark: #2c2c2c;
    --transition: all 0.3s ease;
}

body.light-mode {
    --bg-color: var(--light-bg);
    --text-color: var(--light-text);
    --card-bg: var(--card-bg-light);
}

body.dark-mode {
    --bg-color: var(--dark-bg);
    --text-color: var(--dark-text);
    --card-bg: var(--card-bg-dark);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    transition: var(--transition);
}

.container {
    max-width: 1100px;
    margin: auto;
    overflow: hidden;
    padding: 0 2rem;
}

/* Header & Navigation */
header {
    background: var(--primary-color);
    color: #fff;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header #logo {
    height: 50px;
    transition: transform 0.3s ease;
}

header #logo:hover {
    transform: scale(1.1);
}

header nav ul {
    display: flex;
    list-style: none;
    align-items: center;
}

header nav li {
    margin-left: 20px;
}

header nav a {
    color: #fff;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

header nav a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: var(--secondary-color);
    transition: var(--transition);
}

header nav a:hover::after {
    width: 100%;
}

.theme-btn {
    background: transparent;
    border: none;
    color: #fff;
    font-size: 1.2rem;
    cursor: pointer;
    padding: 5px;
    transition: var(--transition);
}

.theme-btn:hover {
    color: var(--secondary-color);
    transform: rotate(20deg);
}

/* Hero Section */
#hero {
    height: 80vh;
    background: linear-gradient(rgba(0,0,0,0.7), rgba(0,0,0,0.7)), url('assets/project1.jpg') no-repeat center center/cover;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: #fff;
}

#hero h1 {
    font-size: 4rem;
    margin-bottom: 1rem;
    animation: fadeInDown 1s ease;
}

#hero p {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    animation: fadeInUp 1s ease 0.5s both;
}

.btn {
    display: inline-block;
    padding: 12px 30px;
    background: var(--secondary-color);
    color: #fff;
    text-decoration: none;
    border-radius: 50px;
    transition: var(--transition);
    animation: fadeInUp 1s ease 1s both;
}

.btn:hover {
    background: #2980b9;
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(52, 152, 219, 0.4);
}

/* Projects Section */
#projects {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    margin-bottom: 50px;
    font-size: 2.5rem;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--secondary-color);
    margin: 10px auto;
}

.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.project-card {
    background: var(--card-bg);
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
    transition: var(--transition);
}

.project-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.2);
}

.project-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.card-content {
    padding: 20px;
}

.card-content h3 {
    margin-bottom: 10px;
    color: var(--secondary-color);
}

/* Contact Section */
#contact {
    padding: 80px 0;
    background: var(--primary-color);
    color: #fff;
    text-align: center;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 20px;
    margin-top: 30px;
}

.contact-info p {
    font-size: 1.1rem;
}

.contact-info i {
    margin-right: 10px;
    color: var(--secondary-color);
}

.contact-info a {
    color: #fff;
    text-decoration: none;
    transition: var(--transition);
}

.contact-info a:hover {
    color: var(--secondary-color);
}

/* Footer */
footer {
    background: #111;
    color: #777;
    padding: 20px 0;
    text-align: center;
}

/* Animations */
@keyframes fadeInDown {
    from { opacity: 0; transform: translateY(-30px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s ease-out;
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive */
@media (max-width: 768px) {
    #hero h1 { font-size: 2.5rem; }
    header .container { flex-direction: column; }
    header nav ul { margin-top: 1rem; }
    header nav li { margin: 0 10px; }
}