:root {
    --bg-color: #0d1117;
    --text-color: #c9d1d9;
    --highlight-color: #58a6ff; 
    --secondary-color: #8b949e;
    --card-bg: #161b22;
    --border-color: #30363d;
    --font-heading: 'Inter', sans-serif;
    --font-mono: 'Fira Code', monospace;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-heading);
    line-height: 1.6;
    scroll-behavior: smooth;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header & Nav */
header {
    padding: 20px 0;
    position: sticky;
    top: 0;
    background-color: rgba(13, 17, 23, 0.9);
    backdrop-filter: blur(10px);
    z-index: 100;
}

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

.logo {
    font-family: var(--font-mono);
    font-weight: 600;
    font-size: 1.2rem;
    color: var(--highlight-color);
}

.cursor {
    animation: blink 1s step-end infinite;
}

@keyframes blink {
    50% { opacity: 0; }
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-size: 0.95rem;
    transition: color 0.3s;
}

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

/* Typography & Sections */
h1, h2, h3 {
    color: #fff;
}

h1 {
    font-size: 3rem;
    margin-bottom: 20px;
}

h2 {
    font-family: var(--font-mono);
    font-size: 1.8rem;
    margin-bottom: 30px;
    position: relative;
    display: inline-block;
}

h2::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: var(--highlight-color);
    transition: width 0.3s;
}

section:hover h2::after {
    width: 100%;
}

section {
    padding: 80px 0;
}

.highlight {
    color: var(--highlight-color);
}

.subtitle {
    font-size: 1.5rem;
    color: var(--secondary-color);
    margin-bottom: 40px;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 6px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    cursor: pointer;
    border: none;
    font-family: var(--font-heading);
}

.primary {
    background-color: var(--highlight-color);
    color: #0d1117;
}

.primary:hover {
    background-color: #79c0ff;
    transform: translateY(-2px);
}

.secondary {
    background-color: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-color);
    margin-left: 10px;
}

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

/* Projects Grid */
.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}

.project-card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    padding: 25px;
    border-radius: 8px;
    transition: transform 0.3s, border-color 0.3s;
}

.project-card:hover {
    transform: translateY(-5px);
    border-color: var(--highlight-color);
}

.project-card h3 {
    margin-bottom: 15px;
}

.project-card p {
    color: var(--secondary-color);
    margin-bottom: 20px;
    font-size: 0.95rem;
}

.tags {
    display: flex;
    gap: 10px;
    margin-bottom: 20px;
}

.tags span {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--highlight-color);
    background-color: rgba(88, 166, 255, 0.1); /* transparent highlight */
    padding: 4px 8px;
    border-radius: 4px;
}

.project-link {
    display: inline-block;
    text-decoration: none;
    color: var(--text-color);
    font-size: 0.9rem;
    font-weight: 600;
}

.project-link:hover {
    text-decoration: underline;
}

/* Contact & Footer */
.email-container {
    margin: 30px 0;
}

.hidden {
    display: none;
}

.social-links {
    margin-top: 20px;
}

.social-links a {
    margin-right: 20px;
    color: var(--secondary-color);
    text-decoration: none;
    font-size: 1.1rem;
}

.social-links a:hover {
    color: var(--highlight-color);
}

footer {
    border-top: 1px solid var(--border-color);
    padding: 40px 0;
    margin-top: 40px;
    text-align: center;
    color: var(--secondary-color);
    font-size: 0.9rem;
}

/* Animations */
.fade-in {
    opacity: 0;
    animation: fadeInUp 0.8s ease forwards;
}

.fade-in-delay {
    opacity: 0;
    animation: fadeInUp 0.8s ease 0.2s forwards;
}

.fade-in-delay-2 {
    opacity: 0;
    animation: fadeInUp 0.8s ease 0.4s forwards;
}

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

/* Mobile Responsiveness */
@media (max-width: 600px) {
    h1 { font-size: 2.2rem; }
    .nav-links {
        display: none; /* Simplification for basics, a hamburger menu could be added */
    }
    .secondary { margin-left: 0; margin-top: 10px; display: block; text-align: center;}
    .btn { width: 100%; text-align: center; }
}