:root {
    /* Material Light Theme Colors */
    --md-background: #f5f5f5;
    --md-surface: #ffffff;
    --md-surface-2: #eeeeee;
    --md-primary: #6200ee;
    --md-primary-variant: #3700b3;
    --md-secondary: #018786;
    --md-error: #b00020;
    --md-on-background: #000000;
    --md-on-surface: #000000;
    --md-on-primary: #ffffff;
    
    /* Elevations (Shadows) */
    --elevation-1: 0 1px 3px rgba(0,0,0,0.12), 0 1px 2px rgba(0,0,0,0.24);
    --elevation-2: 0 3px 6px rgba(0,0,0,0.16), 0 3px 6px rgba(0,0,0,0.23);
    --elevation-4: 0 10px 20px rgba(0,0,0,0.19), 0 6px 6px rgba(0,0,0,0.23);
    --elevation-8: 0 19px 38px rgba(0,0,0,0.30), 0 15px 12px rgba(0,0,0,0.22);
}

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

body {
    font-family: 'Roboto Mono', monospace;
    background-color: var(--md-background);
    color: var(--md-on-background);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Material Elevations */
.elevation-1 { box-shadow: var(--elevation-1); }
.elevation-2 { box-shadow: var(--elevation-2); }
.elevation-4 { box-shadow: var(--elevation-4); }
.elevation-8 { box-shadow: var(--elevation-8); }

/* Typography */
h1, h2, h3, h4 {
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--md-on-surface);
}

.primary-text { color: var(--md-primary); }
.secondary-text { color: var(--md-secondary); }

/* Navigation */
.navbar {
    background-color: var(--md-surface);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    padding: 1rem 0;
}

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

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--md-primary);
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 20px;
}

.nav-links a {
    color: var(--md-on-surface);
    text-decoration: none;
    transition: color 0.3s;
    font-weight: 500;
}

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

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 80px;
}

.hero-text h1 { font-size: 3.5rem; margin-bottom: 0.5rem; }
.hero-text h2 { font-size: 1.5rem; margin-bottom: 1.5rem; font-weight: 400; }
.hero-text p { max-width: 600px; margin-bottom: 2rem; color: #555; }

.hero-actions {
    display: flex;
    gap: 15px;
}

/* Buttons */
.btn {
    padding: 10px 24px;
    border: none;
    border-radius: 4px;
    font-family: 'Roboto Mono', monospace;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    transition: background-color 0.3s, transform 0.1s;
    text-transform: uppercase;
    letter-spacing: 1px;
}

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

.btn-primary {
    background-color: var(--md-primary);
    color: var(--md-on-primary);
}
.btn-primary:hover { background-color: #d4a5ff; }

.btn-outline {
    background-color: transparent;
    color: var(--md-primary);
    border: 2px solid var(--md-primary);
}
.btn-outline:hover { background-color: rgba(187, 134, 252, 0.1); }

/* Sections */
.section {
    padding: 80px 0;
}
.section-title {
    font-size: 2rem;
    border-bottom: 2px solid var(--md-surface-2);
    padding-bottom: 10px;
    margin-bottom: 40px;
    color: var(--md-primary);
}

/* Cards */
.card {
    background-color: var(--md-surface);
    border-radius: 8px;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--elevation-4);
}

/* Projects Grid */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.project-img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    border-bottom: 1px solid var(--md-surface-2);
}

.project-content {
    padding: 20px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.project-title {
    font-size: 1.2rem;
    margin-bottom: 10px;
}

.project-desc {
    color: #555;
    font-size: 0.9rem;
    margin-bottom: 15px;
    flex-grow: 1;
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 15px;
}

.tag {
    background-color: var(--md-surface-2);
    color: var(--md-secondary);
    padding: 4px 10px;
    border-radius: 16px;
    font-size: 0.8rem;
}

/* Skills Grid */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
}

.skill-category {
    background-color: var(--md-surface);
    padding: 20px;
    border-radius: 8px;
}
.skill-category h3 { color: var(--md-secondary); font-size: 1.1rem;}
.skill-category ul { list-style-type: none; padding-left: 10px; }
.skill-category li { margin-bottom: 8px; font-size: 0.95rem; }
.skill-category li::before { content: "> "; color: var(--md-primary); }

/* Timeline (Experience/Education) */
.timeline-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.timeline-item {
    background-color: var(--md-surface);
    padding: 20px;
    border-radius: 8px;
    margin-bottom: 20px;
    border-left: 4px solid var(--md-primary);
}
.timeline-date { color: var(--md-secondary); font-size: 0.85rem; margin-bottom: 5px;}
.timeline-title { font-weight: 700; margin-bottom: 5px; }
.timeline-subtitle { color: #555; font-size: 0.9rem; margin-bottom: 10px;}


/* Footer */
.footer {
    background-color: var(--md-surface);
    padding: 30px 0;
    margin-top: 50px;
    font-size: 0.9rem;
    color: #555;
}
.text-center { text-align: center; }

/* Specific Article Layouts */
.section-intro {
    font-size: 1.1rem;
    color: #444;
    margin-bottom: 30px;
    font-style: italic;
}

.methodology-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
    margin-bottom: 40px;
}

.methodology-item img {
    width: 70%;
    margin: 0 auto;
    display: block;
    border-radius: 8px;
    box-shadow: var(--elevation-2);
    padding: 4%;
    background-color: #fff;
    box-sizing: border-box;
}

.results-item {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
    align-items: center;
    margin-bottom: 40px;
}

.results-item img {
    width: 70%;
    margin: 0 auto;
    display: block;
    border-radius: 8px;
    box-shadow: var(--elevation-1);
    transition: transform 0.2s;
    padding: 4%;
    background-color: #fff;
    box-sizing: border-box;
}

.results-item img:hover {
    transform: scale(1.05);
}

/* Contact Section */
.contact-intro {
    color: #555;
    font-size: 1rem;
    margin-bottom: 40px;
    max-width: 650px;
    line-height: 1.8;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.contact-card {
    display: block;
    background-color: var(--md-surface);
    padding: 35px 20px;
    border-radius: 12px;
    text-align: center;
    text-decoration: none;
    color: var(--md-on-surface);
    transition: transform 0.3s, box-shadow 0.3s, border-color 0.3s;
    border: 1px solid var(--md-surface-2);
    border-top: 4px solid var(--md-primary);
    position: relative;
    overflow: hidden;
}

.contact-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(98, 0, 238, 0.03), rgba(1, 135, 134, 0.03));
    opacity: 0;
    transition: opacity 0.3s;
}

.contact-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--elevation-4);
    border-top-color: var(--md-secondary);
}

.contact-card:hover::before {
    opacity: 1;
}

.contact-card i {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    margin: 0 auto 16px;
    font-size: 1.6rem;
    color: var(--md-on-primary);
    background: linear-gradient(135deg, var(--md-primary), var(--md-primary-variant));
    border-radius: 50%;
    position: relative;
    z-index: 1;
}

.contact-card h3 {
    font-size: 1rem;
    margin-bottom: 8px;
    color: var(--md-on-surface);
    font-weight: 700;
    position: relative;
    z-index: 1;
}

.contact-card p {
    font-size: 0.85rem;
    color: var(--md-secondary);
    font-weight: 500;
    position: relative;
    z-index: 1;
}

/* Responsive */
@media (max-width: 768px) {
    .timeline-container { grid-template-columns: 1fr; }
    .hero-text h1 { font-size: 2.5rem; }
    .modal-content { width: 95%; margin: 10% auto; }
    .methodology-layout, .results-layout { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr 1fr; }
    .nav-links { gap: 10px; font-size: 0.85rem; }
}