/* Base Styles */
:root {
    --primary-color: #005a87;
    --secondary-color: #00a4bd;
    --accent-color: #f7b500;
    --text-color: #333;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
    --border-radius: 8px;
    --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

* {
    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: #f5f7fa;
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

h1, h2, h3, h4, h5, h6 {
    margin-bottom: 1rem;
    line-height: 1.3;
    color: var(--primary-color);
}

p {
    margin-bottom: 1rem;
}

a {
    color: var(--secondary-color);
    text-decoration: none;
    transition: var(--transition);
}

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

ul {
    list-style: none;
}

section {
    padding: 5rem 0;
}

.btn {
    display: inline-block;
    background-color: var(--secondary-color);
    color: white;
    padding: 0.8rem 1.5rem;
    border-radius: var(--border-radius);
    text-decoration: none;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-weight: 600;
}

.btn:hover {
    background-color: var(--primary-color);
    color: white;
    transform: translateY(-3px);
    box-shadow: var(--box-shadow);
}

/* Header Styles */
header {
    background-color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 15px;
}

.logo h1 {
    font-size: 1.5rem;
    margin-bottom: 0;
}

.logo p {
    font-size: 0.9rem;
    margin-bottom: 0;
    color: var(--secondary-color);
}

nav ul {
    display: flex;
}

nav ul li {
    margin-left: 1.5rem;
}

nav ul li a {
    color: var(--text-color);
    font-weight: 500;
}

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

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 8rem 0;
    text-align: center;
}

.hero h1, .hero h2 {
    color: white;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 0.5rem;
}

.hero h2 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    font-weight: 400;
}

.hero p {
    font-size: 1.2rem;
    max-width: 800px;
    margin: 0 auto 2rem;
}

.hero .btn {
    background-color: var(--accent-color);
    color: var(--dark-color);
    font-size: 1.1rem;
    padding: 1rem 2rem;
}

.hero .btn:hover {
    background-color: white;
}

/* Overview Section */
.overview {
    background-color: white;
}

.overview h2 {
    text-align: center;
    margin-bottom: 3rem;
}

.overview-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.overview-text p {
    font-size: 1.1rem;
}

.overview-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
}

.feature {
    background-color: var(--light-color);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.feature:hover {
    transform: translateY(-5px);
}

.feature i {
    font-size: 2rem;
    color: var(--secondary-color);
    margin-bottom: 1rem;
}

.feature h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

/* Phases Section */
.phases {
    background-color: var(--light-color);
}

.phases h2 {
    text-align: center;
    margin-bottom: 3rem;
}

.timeline {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
}

.timeline::after {
    content: '';
    position: absolute;
    width: 6px;
    background-color: var(--secondary-color);
    top: 0;
    bottom: 0;
    left: 50%;
    margin-left: -3px;
}

.phase {
    position: relative;
    width: 50%;
    padding: 10px 40px;
    box-sizing: border-box;
}

.phase:nth-child(odd) {
    left: 0;
}

.phase:nth-child(even) {
    left: 50%;
}

.phase-year {
    position: absolute;
    width: 120px;
    height: 40px;
    background-color: var(--accent-color);
    top: 20px;
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    color: var(--dark-color);
    z-index: 1;
}

.phase:nth-child(odd) .phase-year {
    right: -60px;
}

.phase:nth-child(even) .phase-year {
    left: -60px;
}

.phase-content {
    padding: 20px;
    background-color: white;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    position: relative;
}

.phase-content::after {
    content: '';
    position: absolute;
    width: 20px;
    height: 20px;
    background-color: white;
    border: 4px solid var(--secondary-color);
    border-radius: 50%;
    top: 20px;
    z-index: 1;
}

.phase:nth-child(odd) .phase-content::after {
    right: -50px;
}

.phase:nth-child(even) .phase-content::after {
    left: -50px;
}

.phase-content h3 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.phase-content ul li {
    margin-bottom: 0.5rem;
    position: relative;
    padding-left: 1.5rem;
}

.phase-content ul li::before {
    content: '•';
    color: var(--secondary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* Themes Section */
.themes {
    background-color: white;
}

.themes h2 {
    text-align: center;
    margin-bottom: 3rem;
}

.themes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.theme-card {
    background-color: var(--light-color);
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.theme-card:hover {
    transform: translateY(-5px);
}

.theme-icon {
    background-color: var(--primary-color);
    color: white;
    padding: 2rem;
    text-align: center;
}

.theme-icon i {
    font-size: 3rem;
}

.theme-card h3 {
    padding: 1.5rem 1.5rem 0.5rem;
    text-align: center;
    font-size: 1.3rem;
}

.progression {
    padding: 0 1.5rem 1.5rem;
}

.step {
    display: flex;
    align-items: center;
    margin-bottom: 0.8rem;
}

.step span {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 30px;
    height: 30px;
    background-color: var(--secondary-color);
    color: white;
    border-radius: 50%;
    margin-right: 1rem;
    flex-shrink: 0;
}

.step p {
    margin-bottom: 0;
    font-size: 0.9rem;
}

/* Models Section */
.models {
    background-color: var(--light-color);
}

.models h2 {
    text-align: center;
    margin-bottom: 3rem;
}

.models-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.model-card {
    background-color: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.model-card:hover {
    transform: translateY(-5px);
}

.model-image {
    height: 200px;
    position: relative;
    background-size: cover;
    background-position: center;
}

.model-image.chemistry {
    background-image: url('https://images.unsplash.com/photo-1603126857599-f6e157fa2fe6?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80');
}

.model-image.math {
    background-image: url('https://images.unsplash.com/photo-1509228468518-180dd4864904?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80');
}

.model-image.digital-twin {
    background-image: url('https://images.unsplash.com/photo-1581092921461-7d65ca45393a?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80');
}

.model-image.physics {
    background-image: url('https://images.unsplash.com/photo-1462331940025-496dfbfc7564?ixlib=rb-1.2.1&auto=format&fit=crop&w=1350&q=80');
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 90, 135, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.overlay h3 {
    color: white;
    text-align: center;
    margin-bottom: 0;
}

.model-content {
    padding: 1.5rem;
}

.model-content h4 {
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.model-content ul {
    margin-bottom: 1.5rem;
}

.model-content ul li {
    margin-bottom: 0.5rem;
    position: relative;
    padding-left: 1.5rem;
}

.model-content ul li::before {
    content: '•';
    color: var(--secondary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

.btn-modal {
    background-color: var(--secondary-color);
    color: white;
    border: none;
    padding: 0.6rem 1.2rem;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 600;
}

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

/* Implementation Section */
.implementation {
    background-color: white;
}

.implementation h2 {
    text-align: center;
    margin-bottom: 3rem;
}

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

.implementation-card {
    background-color: var(--light-color);
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.implementation-card:hover {
    transform: translateY(-5px);
}

.implementation-icon {
    text-align: center;
    margin-bottom: 1.5rem;
}

.implementation-icon i {
    font-size: 3rem;
    color: var(--secondary-color);
}

.implementation-card h3 {
    text-align: center;
    margin-bottom: 1.5rem;
}

.implementation-card ul li {
    margin-bottom: 0.8rem;
    position: relative;
    padding-left: 1.5rem;
}

.implementation-card ul li::before {
    content: '•';
    color: var(--secondary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* Alignment Section */
.alignment {
    background-color: var(--light-color);
}

.alignment h2 {
    text-align: center;
    margin-bottom: 3rem;
}

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

.pillar {
    background-color: white;
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    transition: var(--transition);
}

.pillar:hover {
    transform: translateY(-5px);
}

.pillar-icon {
    text-align: center;
    margin-bottom: 1.5rem;
}

.pillar-icon i {
    font-size: 3rem;
    color: var(--secondary-color);
}

.pillar h3 {
    text-align: center;
    margin-bottom: 1.5rem;
}

.pillar ul li {
    margin-bottom: 0.8rem;
    position: relative;
    padding-left: 1.5rem;
}

.pillar ul li::before {
    content: '•';
    color: var(--secondary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* Conclusion Section */
.conclusion {
    background-color: white;
    text-align: center;
}

.conclusion p {
    max-width: 800px;
    margin: 0 auto 1.5rem;
    font-size: 1.1rem;
}

.conclusion .btn {
    margin-top: 1rem;
}

/* Footer */
footer {
    background-color: var(--dark-color);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    margin-bottom: 2rem;
}

.footer-logo h3 {
    color: white;
    margin-bottom: 0.5rem;
}

.footer-logo p {
    color: var(--secondary-color);
}

.footer-links h4 {
    color: white;
    margin-bottom: 1rem;
}

.footer-links ul li {
    margin-bottom: 0.5rem;
}

.footer-links ul li a {
    color: #ccc;
}

.footer-links ul li a:hover {
    color: white;
}

.copyright {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.copyright p {
    font-size: 0.9rem;
    color: #ccc;
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 1100;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0, 0, 0, 0.7);
}

.modal-content {
    background-color: white;
    margin: 5% auto;
    padding: 2rem;
    border-radius: var(--border-radius);
    width: 90%;
    max-width: 1000px;
    position: relative;
    animation: modalopen 0.5s;
}

@keyframes modalopen {
    from {opacity: 0; transform: translateY(-50px);}
    to {opacity: 1; transform: translateY(0);}
}

.close {
    position: absolute;
    top: 1rem;
    right: 1.5rem;
    color: var(--dark-color);
    font-size: 2rem;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: var(--secondary-color);
}

.modal-content h2 {
    text-align: center;
    margin-bottom: 2rem;
}

.modal-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
}

.modal-section h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
}

.modal-section ul li {
    margin-bottom: 0.5rem;
    position: relative;
    padding-left: 1.5rem;
}

.modal-section ul li::before {
    content: '•';
    color: var(--secondary-color);
    font-weight: bold;
    position: absolute;
    left: 0;
}

/* Responsive Styles */
@media (max-width: 992px) {
    .overview-content {
        grid-template-columns: 1fr;
    }
    
    .timeline::after {
        left: 31px;
    }
    
    .phase {
        width: 100%;
        padding-left: 70px;
        padding-right: 25px;
    }
    
    .phase:nth-child(even) {
        left: 0;
    }
    
    .phase-year {
        left: -10px !important;
        right: auto !important;
    }
    
    .phase-content::after {
        left: -40px !important;
        right: auto !important;
    }
    
    .footer-content {
        flex-direction: column;
    }
    
    .footer-logo, .footer-links {
        margin-bottom: 2rem;
    }
}

@media (max-width: 768px) {
    header .container {
        flex-direction: column;
    }
    
    .logo {
        margin-bottom: 1rem;
        text-align: center;
    }
    
    nav ul {
        flex-wrap: wrap;
        justify-content: center;
    }
    
    nav ul li {
        margin: 0.5rem;
    }
    
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero h2 {
        font-size: 1.5rem;
    }
    
    .overview-features {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 576px) {
    .hero h1 {
        font-size: 2rem;
    }
    
    .hero h2 {
        font-size: 1.2rem;
    }
    
    .hero p {
        font-size: 1rem;
    }
    
    .modal-content {
        padding: 1rem;
    }
}