/* Base Variables & Reset */
:root {
    --bg-color: #050505;
    --text-primary: rgba(255, 255, 255, 0.9);
    --text-secondary: rgba(255, 255, 255, 0.6);
    --accent-color: #00f2ff;
    /* Electric Blue */
    --accent-glow: rgba(0, 242, 255, 0.3);
    --card-bg: rgba(255, 255, 255, 0.03);
    --card-border: rgba(255, 255, 255, 0.05);
    --font-heading: 'Playfair Display', serif;
    --font-body: 'Outfit', sans-serif;
    --transition-speed: 0.3s;
}

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

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-body);
    line-height: 1.6;
    overflow-x: hidden;
}

/* Typography */
h1,
h2,
h3,
h4 {
    font-family: var(--font-heading);
    color: var(--text-primary);
    font-weight: 700;
}

p {
    color: var(--text-secondary);
}

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

ul {
    list-style: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.section {
    padding: 6rem 0;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 3rem;
    text-align: center;
    position: relative;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.6s ease-out;
}

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

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 3px;
    background: var(--accent-color);
    margin: 1rem auto 0;
    box-shadow: 0 0 10px var(--accent-glow);
}

/* Navigation */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    padding: 1.5rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    z-index: 1000;
    transition: background-color 0.3s ease;
}

.navbar.scrolled {
    background-color: rgba(5, 5, 5, 0.9);
    backdrop-filter: blur(10px);
    padding: 1rem 2rem;
}

.logo {
    font-family: var(--font-heading);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 1px;
}

.nav-links {
    display: flex;
    gap: 2rem;
}

.nav-links a {
    font-size: 0.95rem;
    color: var(--text-secondary);
    position: relative;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text-primary);
}

.nav-links a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -5px;
    left: 0;
    background-color: var(--accent-color);
    transition: width 0.3s ease;
    box-shadow: 0 0 8px var(--accent-glow);
}

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

.hamburger {
    display: none;
    cursor: pointer;
    flex-direction: column;
    gap: 5px;
}

.bar {
    width: 25px;
    height: 2px;
    background-color: var(--text-primary);
    transition: 0.3s;
}

/* Mobile Menu */
.mobile-menu {
    position: fixed;
    top: 0;
    left: 100%;
    width: 100%;
    height: 100vh;
    background-color: var(--bg-color);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    transition: 0.4s ease-in-out;
    z-index: 999;
}

.mobile-menu.active {
    left: 0;
}

.mobile-link {
    font-family: var(--font-heading);
    font-size: 2rem;
    color: var(--text-primary);
}

/* Hero Section */
.hero-section {
    position: relative;
    height: 100vh;
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: left;
    overflow: hidden;
}

.video-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -2;
}

#hero-video {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.video-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: -1;
}

.hero-content {
    z-index: 1;
    z-index: 1;
    padding: 0 2rem;
    width: 100%;
    max-width: 1200px;
}

.hero-content h1 {
    font-size: 4rem;
    margin-bottom: 0.5rem;
    letter-spacing: -1px;
}

.hero-content .subtitle {
    font-size: 1.5rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 2px;
    text-shadow: 0 0 10px var(--accent-glow);
}

.hero-content .tagline {
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 0 2.5rem 0;
}

.cta-button {
    display: inline-block;
    padding: 1rem 2.5rem;
    border: 1px solid var(--accent-color);
    color: var(--accent-color);
    font-size: 1rem;
    border-radius: 50px;
    transition: all 0.3s ease;
    background: transparent;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.cta-button:hover {
    background: var(--accent-glow);
    color: #fff;
    box-shadow: 0 0 20px var(--accent-glow);
}

.scroll-down {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    color: var(--text-secondary);
    font-size: 1.5rem;
    animation: bounce 2s infinite;
}

@keyframes bounce {

    0%,
    20%,
    50%,
    80%,
    100% {
        transform: translate(-50%, 0);
    }

    40% {
        transform: translate(-50%, -10px);
    }

    60% {
        transform: translate(-50%, -5px);
    }
}

/* Animations */
.fade-in-up {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeInUp 1s forwards;
}

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

.delay-1 {
    animation-delay: 0.2s;
}

.delay-2 {
    animation-delay: 0.4s;
}

.delay-3 {
    animation-delay: 0.6s;
}

.delay-4 {
    animation-delay: 0.8s;
}

.delay-3s {
    animation-delay: 3s;
}

.delay-2s {
    animation-delay: 2s;
}

/* About Section */
.about-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 4rem;
    align-items: start;
}

.about-text p {
    margin-bottom: 1.5rem;
    font-size: 1.1rem;
}

.focus-areas h3 {
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.focus-areas ul li {
    margin-bottom: 1rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 1.05rem;
}

.focus-areas ul li i {
    color: var(--accent-color);
    width: 20px;
}

/* Skills Section */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.skill-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    padding: 2rem;
    text-align: center;
    border-radius: 12px;
    transition: all 0.3s ease;
}

.skill-card:hover {
    transform: translateY(-5px);
    border-color: var(--accent-color);
    box-shadow: 0 5px 20px rgba(0, 242, 255, 0.1);
}

.skill-card img.skill-icon {
    width: 60px;
    height: 60px;
    max-width: 60px;
    max-height: 60px;
    object-fit: contain;
    display: block;
    margin: 0 auto 1rem auto;
    transition: transform 0.3s;
    filter: none;
    opacity: 1;
}

.skill-card i {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}


.skill-card:hover i,
.skill-card:hover img.skill-icon {
    color: var(--accent-color);
    transform: scale(1.1);
}

.skill-card h3 {
    font-size: 1rem;
    font-family: var(--font-body);
    font-weight: 400;
}

/* Projects Section */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2.5rem;
}

.project-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    overflow: hidden;
    transition: 0.3s;
    height: 100%;
}

.project-card:hover {
    transform: translateY(-5px);
    border-color: rgba(255, 255, 255, 0.2);
}

.project-info {
    padding: 1.5rem 2rem 2rem;
}

.project-insight {
    font-size: 0.95rem;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.project-points {
    list-style: disc;
    padding-left: 1.2rem;
    margin-bottom: 1.5rem;
    color: var(--text-secondary);
}

.project-points li {
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

/* Project Slider */
.slider-container {
    position: relative;
    width: 100%;
    height: 200px;
    overflow: hidden;
    border-bottom: 1px solid var(--card-border);
}

.slider-wrapper {
    display: flex;
    height: 100%;
    transition: transform 0.5s ease-in-out;
}

.slider-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    flex-shrink: 0;
}

.slider-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background: rgba(0, 0, 0, 0.5);
    color: white;
    border: none;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: 0.3s;
    opacity: 0;
}

.slider-container:hover .slider-btn {
    opacity: 1;
}

.slider-btn:hover {
    background: var(--accent-color);
    color: black;
}

.prev-btn {
    left: 10px;
}

.next-btn {
    right: 10px;
}

.project-info h3 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
    cursor: pointer;
    transition: color 0.3s ease;
}

.project-info h3.active-title {
    color: orange;
    font-weight: bold;
}

.project-info p {
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

.tech-stack {
    display: flex;
    gap: 0.8rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
}

.tech-stack li {
    font-size: 0.8rem;
    color: var(--accent-color);
    background: rgba(0, 242, 255, 0.05);
    padding: 0.4rem 0.8rem;
    border-radius: 50px;
    border: 1px solid rgba(0, 242, 255, 0.1);
}

.project-links {
    display: flex;
    gap: 1rem;
}

.btn-small {
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-primary);
    opacity: 0.8;
}

.btn-small:hover {
    opacity: 1;
    color: var(--accent-color);
}

/* Contact Section */
.contact-content-centered {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 3rem;
}

.contact-content-centered p {
    font-size: 1.25rem;
    max-width: 600px;
}

.social-links-large {
    display: flex;
    gap: 3rem;
    flex-wrap: wrap;
    justify-content: center;
}

.social-icon-large {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    color: var(--text-secondary);
    transition: 0.3s;
    font-size: 1rem;
}

.social-icon-large i {
    font-size: 3rem;
    transition: 0.3s;
}

.social-icon-large:hover {
    color: var(--accent-color);
    transform: translateY(-5px);
}

.social-icon-large:hover i {
    text-shadow: 0 0 15px var(--accent-glow);
}

/* Footer */
footer {
    padding: 2rem;
    text-align: center;
    border-top: 1px solid var(--card-border);
    margin-top: 4rem;
}

footer p {
    font-size: 0.9rem;
}

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

    .nav-links {
        display: none;
    }

    .hamburger {
        display: flex;
    }

    .hero-content {
        padding: 0 1.5rem;
    }

    .hero-content h1 {
        font-size: 2.5rem;
        margin-bottom: 0.5rem;
    }

    .hero-content .subtitle {
        font-size: 1.1rem;
        margin-bottom: 1.5rem;
    }

    .section {
        padding: 4rem 0;
        /* Reduced vertical padding for mobile */
    }

    .section-title {
        font-size: 2rem;
        margin-bottom: 2rem;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2.5rem;
        /* Better gap for stacked content */
    }

    .skills-grid {
        grid-template-columns: repeat(2, 1fr);
        /* Ensure 2 columns on mobile */
        gap: 1.5rem;
    }

    .contact-content-centered {
        gap: 2rem;
    }

    .social-links-large {
        gap: 2rem;
        /* Reduced gap for social icons */
    }
}

.video-container {
    position: absolute;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.video-container video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: -2;
}

.video-overlay {
    position: absolute;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    z-index: -1;
}

.publications {
    padding: var(--section-spacing) 0;
    background-color: rgba(5, 5, 5, 0.9);
}

.publication-list {
    display: grid;
    gap: 1.5rem;
    max-width: 900px;
    margin: 0 auto;
}

.pub-card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-md);
    padding: 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    /* Vertical center */
    transition: var(--transition);
}

.pub-card:hover {
    border-color: var(--primary-color);
    background-color: var(--surface-hover);
}

.pub-content h4 {
    margin-bottom: 0.5rem;
    cursor: pointer;
}

.pub-link {
    color: var(--primary-color);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    white-space: nowrap;
}

/* Contact */
.contact {
    padding: var(--section-spacing) 0;
    margin-bottom: 4rem;
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.contact-card {
    background-color: var(--surface-color);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    text-align: center;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.contact-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary-color);
    box-shadow: 0 0 15px rgba(59, 130, 246, 0.1);
}

.contact-icon {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.contact-label {
    font-weight: 600;
    color: var(--text-primary);
}

/* Publications Section */
.publications {
    padding: 6rem 0;
    background: rgba(5, 5, 5, 0.9);
}

/* LIST = 1 KOLOM */
.publication-list {
    display: grid;
    grid-template-columns: 1fr;
    /* <-- Kunci 1 kolom */
    gap: 2rem;
    max-width: 900px;
    /* biar tidak terlalu melebar */
    margin: 0 auto;
    /* center */
}

/* Card style = PROJECT CARD */
.pub-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 1.8rem 2rem;
    transition: 0.3s;

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

/* Hover sama seperti project */
.pub-card:hover {
    transform: translateY(-5px);
    border-color: rgba(255, 255, 255, 0.2);
}

/* Judul */
.pub-content h4 {
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

/* Penulis */
.pub-content p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

/* Link tombol */
.pub-link {
    font-weight: 600;
    color: var(--accent-color);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    white-space: nowrap;
}

@media (max-width: 600px) {
    .pub-card {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
}