:root {
    --primary-color: #007BFF;
    --primary-hover: #0056b3;
    --dark-color: #2c3e50;
    --light-color: #ecf0f1;
    --background-color: #ffffff;
    --section-bg-color: #f8f9fa;
}

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

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.7;
    color: #555;
    background-color: var(--background-color);
}

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

h1, h2, h3 {
    font-family: 'Poppins', sans-serif;
    color: var(--dark-color);
    font-weight: 600;
}

/* Navigation */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 2rem;
    position: fixed;
    width: 100%;
    top: 0;
    left: 0;
    background: rgba(255, 255, 255, 0.9);
    -webkit-backdrop-filter: blur(10px);
    backdrop-filter: blur(10px);
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.navbar .logo {
    font-family: 'Poppins', sans-serif;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--dark-color);
    text-decoration: none;
}

.navbar .nav-links {
    list-style: none;
    display: flex;
}

.navbar .nav-links li {
    margin-left: 2rem;
}

.navbar .nav-links a {
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

.navbar .nav-links a:hover {
    color: var(--primary-color);
}

/* Hero Section */
#hero {
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    height: 100vh;
    color: #fff;
    background: linear-gradient(rgba(44, 62, 80, 0.8), rgba(44, 62, 80, 0.8)), url('https://images.unsplash.com/photo-1579546929518-9e396f3cc809?ixlib=rb-4.0.3&ixid=M3wxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8fA%3D%3D&auto=format&fit=crop&w=1770&q=80') center center/cover no-repeat;
}

#hero .hero-content { max-width: 800px; }

#hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    color: #fff;
    font-weight: 700;
}

#hero p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    font-family: 'Poppins', sans-serif;
}

.btn {
    display: inline-block;
    padding: 0.8rem 2rem;
    background: var(--primary-color);
    color: #fff;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 600;
    transition: background 0.3s ease;
    margin: 0 0.5rem;
}

.btn:hover { background: var(--primary-hover); }

/* Sections */
.section {
    padding: 6rem 0;
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.section.visible { opacity: 1; transform: translateY(0); }

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 4rem;
    position: relative;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--primary-color);
    border-radius: 2px;
}

#about { background-color: var(--background-color); }
#process { background-color: var(--section-bg-color); }
#portfolio { background-color: var(--background-color); }
#contact { background-color: var(--section-bg-color); }

/* About Section */
#about p {
    max-width: 800px;
    margin: 1rem auto;
    text-align: center;
    font-size: 1.1rem;
}

/* Process/Timeline Section */
.timeline { position: relative; max-width: 800px; margin: 0 auto; }

.timeline::after {
    content: '';
    position: absolute;
    width: 4px;
    background-color: var(--primary-color);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -2px;
}

.timeline-item {
    padding: 10px 40px;
    position: relative;
    background-color: inherit;
    width: 50%;
    opacity: 0;
    transform: translateX(-100px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.timeline-item.visible { opacity: 1; transform: translateX(0); }

.timeline-item.right { left: 50%; transform: translateX(100px); }

.timeline-item.right.visible { transform: translateX(0); }

.timeline-item::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    right: -10px;
    background-color: white;
    border: 4px solid var(--primary-color);
    top: 25px;
    border-radius: 50%;
    z-index: 1;
}

.timeline-item.right::after { left: -10px; }

.timeline-content {
    padding: 20px 30px;
    background-color: white;
    position: relative;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
}

.timeline-content .timeline-icon { font-size: 2rem; color: var(--primary-color); margin-bottom: 0.5rem; }
.timeline-content h3 { font-size: 1.2rem; font-weight: 700; }

/* Portfolio Section */
.portfolio-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 2rem; }

.portfolio-item {
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.portfolio-item:hover { transform: translateY(-10px); box-shadow: 0 8px 25px rgba(0,0,0,0.15); }

.portfolio-item img { width: 100%; height: 250px; object-fit: cover; display: block; }

.portfolio-content { padding: 1.5rem; }

.portfolio-content h3 { font-size: 1.25rem; margin-bottom: 0.5rem; }

.portfolio-content p { font-size: 0.95rem; margin-bottom: 1rem; }

.portfolio-content .btn { padding: 0.6rem 1.2rem; font-size: 0.9rem; }

/* Contact Section */
#contact .contact-content { text-align: center; }

#contact p { font-size: 1.2rem; margin-bottom: 2rem; }

.contact-info a {
    font-size: 1.5rem;
    color: var(--dark-color);
    text-decoration: none;
    margin: 0 1rem;
    transition: color 0.3s ease;
}

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

/* Footer */
footer { text-align: center; padding: 2rem 0; background: var(--dark-color); color: #fff; }

/* Responsive */
@media (max-width: 768px) {
    .navbar { flex-direction: column; }
    .navbar .nav-links { margin-top: 1rem; }
    .navbar .nav-links li { margin: 0 0.7rem; }

    #hero h1 { font-size: 2.5rem; }
    #hero p { font-size: 1.1rem; }

    .section { padding: 4rem 0; }
    .section-title { font-size: 2rem; }

    .timeline::after { left: 15px; }
    .timeline-item { width: 100%; padding-left: 50px; padding-right: 15px; transform: translateX(30px); }
    .timeline-item.right { left: 0%; transform: translateX(30px); }
    .timeline-item::after, .timeline-item.right::after { left: 6px; }
}