/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
    line-height: 1.6;
    color: #2c3e50;
    background: #f5f7fa;
    min-height: 100vh;
}

/* Navigation */
.navbar {
    background: #ffffff;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 3px solid #3498db;
}

.nav-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: #2c3e50;
    letter-spacing: -0.5px;
}

.nav-menu {
    list-style: none;
    display: flex;
    gap: 3rem;
}

.nav-link {
    text-decoration: none;
    color: #2c3e50;
    font-weight: 500;
    font-size: 1.05rem;
    transition: all 0.3s ease;
    position: relative;
    padding: 0.5rem 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: #3498db;
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.nav-link:hover {
    color: #3498db;
}

/* Container */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 3rem 2rem;
    min-height: calc(100vh - 150px);
}

/* Page Transitions */
.page {
    display: none;
    animation: fadeIn 0.5s ease;
}

.page.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Profile Section */
.profile-section {
    max-width: 900px;
    margin: 0 auto 3rem;
}

.profile-card {
    background: #ffffff;
    border-radius: 16px;
    padding: 4rem 3rem;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    border: 1px solid #e8ecef;
}

.profile-photo {
    width: 180px;
    height: 180px;
    border-radius: 50%;
    object-fit: cover;
    border: 6px solid #3498db;
    margin: 0 auto 2rem;
    display: block;
    box-shadow: 0 8px 25px rgba(52, 152, 219, 0.2);
}

.profile-name {
    color: #2c3e50;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
    letter-spacing: -0.5px;
}

.profile-title {
    color: #7f8c8d;
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    font-weight: 400;
}

.badge {
    display: inline-block;
    background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
    color: white;
    padding: 0.6rem 1.8rem;
    border-radius: 30px;
    font-size: 1rem;
    font-weight: 500;
    box-shadow: 0 4px 15px rgba(52, 152, 219, 0.3);
}

/* Content Section */
.content-section {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.about-card {
    background: #ffffff;
    border-radius: 12px;
    padding: 2.5rem;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.06);
    border: 1px solid #e8ecef;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.about-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
}

.about-card h2 {
    color: #2c3e50;
    font-size: 1.6rem;
    margin-bottom: 1.2rem;
    font-weight: 600;
    border-left: 4px solid #3498db;
    padding-left: 1rem;
}

.about-card p {
    color: #5a6c7d;
    font-size: 1.05rem;
    line-height: 1.8;
    margin-bottom: 1rem;
}

.about-card p:last-child {
    margin-bottom: 0;
}

/* Downloads Page */
.page-header {
    text-align: center;
    margin-bottom: 3rem;
}

.page-header h1 {
    color: #2c3e50;
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.page-subtitle {
    color: #7f8c8d;
    font-size: 1.2rem;
}

.downloads-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
    max-width: 1400px;
    margin: 0 auto;
}

.download-card {
    background: #ffffff;
    border-radius: 12px;
    padding: 2.5rem 2rem;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.06);
    border: 1px solid #e8ecef;
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.download-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #3498db, #2980b9);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.download-card:hover::before {
    transform: scaleX(1);
}

.download-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 35px rgba(0, 0, 0, 0.12);
}

.card-icon {
    color: #3498db;
    margin-bottom: 1.5rem;
    display: flex;
    justify-content: center;
}

.download-card h3 {
    color: #2c3e50;
    font-size: 1.4rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.file-info {
    color: #7f8c8d;
    font-size: 0.95rem;
    margin-bottom: 1.5rem;
}

.download-btn {
    background: linear-gradient(135deg, #3498db 0%, #2980b9 100%);
    color: white;
    border: none;
    padding: 0.9rem 2rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
    font-size: 1rem;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    box-shadow: 0 4px 15px rgba(52, 152, 219, 0.3);
}

.download-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 6px 20px rgba(52, 152, 219, 0.4);
}

.download-btn:active {
    transform: scale(0.98);
}

/* Footer */
.footer {
    background: #2c3e50;
    color: #ecf0f1;
    text-align: center;
    padding: 2rem;
    margin-top: auto;
}

.footer p {
    font-size: 0.95rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-container {
        padding: 0 1rem;
    }

    .nav-brand {
        font-size: 1.2rem;
    }

    .nav-menu {
        gap: 1.5rem;
    }

    .nav-link {
        font-size: 0.95rem;
    }

    .container {
        padding: 2rem 1rem;
    }

    .profile-card {
        padding: 2.5rem 1.5rem;
    }

    .profile-name {
        font-size: 2rem;
    }

    .profile-title {
        font-size: 1.1rem;
    }

    .profile-photo {
        width: 140px;
        height: 140px;
    }

    .content-section {
        grid-template-columns: 1fr;
    }

    .about-card {
        padding: 2rem 1.5rem;
    }

    .page-header h1 {
        font-size: 2rem;
    }

    .downloads-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
}

@media (min-width: 769px) and (max-width: 1024px) {
    .downloads-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1025px) {
    .downloads-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 1400px) {
    .downloads-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}