/* ====== CSS RESET & BASE ====== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #007bff;
    --primary-dark: #0056b3;
    --primary-light: #4dabf7;
    --secondary-color: #1b2a49;
    --accent-color: #10b981;
    --text-color: #2c3e50;
    --text-muted: #6c757d;
    --bg-color: #f8f9fa;
    --white: #ffffff;
    --light-gray: #f1f3f4;
    --border-color: #e9ecef;
    --shadow: 0 2px 15px rgba(0,0,0,0.08);
    --shadow-hover: 0 8px 30px rgba(0,123,255,0.15);
    --shadow-card: 0 4px 20px rgba(0,0,0,0.06);
    --transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    --border-radius: 12px;
    --border-radius-lg: 16px;
    --max-width: 1200px;
    --gradient-primary: linear-gradient(135deg, var(--primary-color), var(--primary-light), var(--accent-color));
    --gradient-overlay: linear-gradient(135deg, rgba(0,0,0,0.6) 0%, rgba(0,0,0,0.3) 50%, rgba(0,0,0,0.1) 100%);
}

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    color: var(--text-color);
    background: var(--bg-color);
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
}

.container {
    width: 90%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* ====== HEADER ====== */
header {
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(20px) saturate(180%);
    box-shadow: 0 1px 20px rgba(0,0,0,0.08);
    position: sticky;
    top: 0;
    z-index: 2000;
    transition: var(--transition);
}

header.scrolled {
    background: rgba(255,255,255,0.98);
    box-shadow: 0 2px 25px rgba(0,0,0,0.12);
}

header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 20px;
}

/* ====== LOGO ====== */
.logo {
    font-size: 1.6rem;
    font-weight: 700;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-decoration: none;
    transition: var(--transition);
    letter-spacing: -0.4px;
    position: relative;
}

.logo::after {
    content: "";
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 3px;
    background: var(--gradient-primary);
    border-radius: 2px;
    transition: width 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.logo:hover::after {
    width: 100%;
}

/* ====== NAVIGATION ====== */
.nav-container {
    position: relative;
}

nav ul {
    list-style: none;
    display: flex;
    align-items: center;
    gap: 25px;
}

nav ul li {
    position: relative;
}

nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-size: 1rem;
    font-weight: 500; /* Changed from 600 to 500 for normal weight */
    padding: 6px 0;
    transition: var(--transition);
    position: relative;
    display: block;
    letter-spacing: -0.2px;
}

nav ul li a::after {
    content: "";
    position: absolute;
    bottom: -6px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--gradient-primary);
    border-radius: 2px;
    transition: width 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

nav ul li a:hover {
    color: var(--primary-color);
    transform: translateY(-1px);
}

nav ul li a:hover::after {
    width: 100%;
}

/* ====== ACTIVE STATE - Only active links are bold ====== */
nav ul li a.active {
    color: var(--primary-color);
    font-weight: 700; /* Bold only for active state */
}

nav ul li a.active::after {
    width: 100%;
    background: var(--gradient-primary);
}

/* ====== DROPDOWN MENU ====== */

        .dropdown {
            position: relative;
        }
        .dropdown-content {
            position: absolute;
            top: 100%;
            left: 0;
            background: white;
            min-width: 250px;
            box-shadow: var(--shadow-xl);
            border-radius: 12px;
            padding: 0.5rem 0;
            opacity: 0;
            visibility: hidden;
            transform: translateY(-10px);
            transition: all 0.3s ease;
            border: 1px solid var(--border-color);
        }
        .dropdown:hover .dropdown-content {
            opacity: 1;
            visibility: visible;
            transform: translateY(0);
        }
        .dropdown-content a {
            display: block;
            padding: 0.75rem 1.5rem;
            color: var(--text-secondary);
            font-size: 0.9rem;
            border-radius: 0;
        }
        .dropdown-content a:hover {
            background: var(--background-light);
            color: var(--primary-color);
        }



/* ====== MOBILE MENU ====== */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    padding: 5px;
    z-index: 2001;
    transition: var(--transition);
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--text-color);
    margin: 2px 0;
    transition: var(--transition);
    border-radius: 2px;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
    background: var(--primary-color);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(6px, -6px);
    background: var(--primary-color);
}

/* ====== LOGIN ICON ====== */
.login-icon {
    padding: 8px;
    border-radius: 50%;
    transition: var(--transition);
}

.login-icon i {
    font-size: 1.5rem;
    transition: var(--transition);
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.login-icon:hover {
    background: rgba(0,123,255,0.1);
    transform: scale(1.1);
}

.login-icon:hover i {
    transform: rotate(360deg);
}

/* ====== HERO SLIDER ====== */
.hero {
    position: relative;
    height: 80vh;
    min-height: 600px;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.slider {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

.slides {
    position: relative;
    width: 100%;
    height: 100%;
}

.slide {
    position: absolute;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    opacity: 0;
    transition: opacity 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.slide.active {
    opacity: 1;
}

.slide::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-overlay);
}

.hero-text {
    position: relative;
    text-align: center;
    color: var(--white);
    z-index: 2;
    max-width: 900px;
    padding: 50px 40px;
    background: rgba(255,255,255,0.08);
    backdrop-filter: blur(20px) saturate(180%);
    border-radius: var(--border-radius-lg);
    border: 1px solid rgba(255,255,255,0.15);
    animation: heroTextAppear 1.2s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.hero-text h1 {
    font-size: clamp(2.2rem, 5vw, 4rem);
    font-weight: 800;
    margin-bottom: 25px;
    text-shadow: 2px 4px 8px rgba(0,0,0,0.3);
    letter-spacing: -1px;
    line-height: 1.2;
}

.hero-text p {
    font-size: clamp(1.1rem, 2.5vw, 1.4rem);
    font-weight: 400;
    opacity: 0.95;
    text-shadow: 1px 2px 4px rgba(0,0,0,0.3);
    line-height: 1.6;
}

@keyframes heroTextAppear {
    from {
        opacity: 0;
        transform: translateY(50px) scale(0.9);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

/* ====== PROFILE SECTION ====== */
.profile {
    background: var(--white);
    padding: 70px 50px;
    margin-top: -60px;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-card);
    position: relative;
    z-index: 1;
    border: 1px solid var(--border-color);
}

.profile::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: var(--gradient-primary);
    border-radius: var(--border-radius-lg) var(--border-radius-lg) 0 0;
}

.profile h2 {
    font-size: 2.5rem;
    margin-bottom: 30px;
    color: var(--secondary-color);
    font-weight: 700;
    text-align: center;
    position: relative;
}

.profile h2::after {
    content: "";
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

.profile p {
    font-size: 1.15rem;
    line-height: 1.9;
    text-align: justify;
    max-width: 950px;
    margin: 0 auto;
    color: var(--text-muted);
}

.profile strong {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
}

/* ====== RESEARCH AREA ====== */
.research-area {
    padding: 100px 0;
    text-align: center;
    position: relative;
}

.research-area::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(0,123,255,0.02) 0%, rgba(231,76,60,0.02) 100%);
    pointer-events: none;
}

.research-area h2 {
    font-size: 2.5rem;
    margin-bottom: 60px;
    color: var(--secondary-color);
    font-weight: 700;
    position: relative;
}

.research-area h2::after {
    content: "";
    position: absolute;
    bottom: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 2px;
}

.research-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
    margin-top: 50px;
    position: relative;
    z-index: 1;
}

.research-card {
    background: var(--white);
    padding: 50px 35px;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.research-card::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 5px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.research-card:hover {
    transform: translateY(-12px);
    box-shadow: var(--shadow-hover);
}

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

.research-card i {
    font-size: 3.5rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 25px;
    transition: var(--transition);
}

.research-card:hover i {
    transform: scale(1.15) rotate(5deg);
}

.research-card h3 {
    font-size: 1.5rem;
    margin-bottom: 18px;
    color: var(--secondary-color);
    font-weight: 700;
    line-height: 1.3;
}

.research-card p {
    font-size: 1.05rem;
    color: var(--text-muted);
    line-height: 1.8;
}

/* ====== RECENT WORK ====== */
.recent-work {
    padding: 100px 0;
    background: var(--white);
    margin-top: 60px;
    position: relative;
}

.recent-work h2 {
    font-size: 2.6rem;
    margin-bottom: 60px;
    text-align: center;
    color: var(--secondary-color);
    font-weight: 800;
    letter-spacing: -0.5px;
    position: relative;
}

.recent-work h2::after {
    content: "";
    position: absolute;
    bottom: -18px;
    left: 50%;
    transform: translateX(-50%);
    width: 100px;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: 3px;
}

.work-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(330px, 1fr));
    gap: 35px;
    margin-top: 50px;
}

.work-card {
    background: var(--white);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    position: relative;
    display: flex;
    flex-direction: column;
    border: 1px solid var(--border-color);

        /* Hapus underline dan set warna default */
    text-decoration: none;
    color: inherit;
}

.work-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-hover);
}

/* Image container with overlay */
.work-card img {
    width: 100%;
    height: 240px;
    object-fit: cover;
    transition: transform 0.6s ease;
}

.work-card::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 240px;
    background: var(--gradient-overlay);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.work-card:hover img {
    transform: scale(1.08);
}

.work-card:hover::after {
    opacity: 1;
}

.work-content {
    padding: 25px;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.work-card h3 {
    font-size: 1.35rem;
    margin-bottom: 12px;
    color: var(--secondary-color);
    font-weight: 700;
    line-height: 1.4;
    transition: color 0.3s ease;
}

.work-card:hover h3 {
    color: var(--primary-color);
}

.work-card p {
    font-size: 0.98rem;
    color: var(--text-muted);
    line-height: 1.7;
    flex-grow: 1;
    transition: opacity 0.3s ease;
}

.work-card:hover p {
    opacity: 0.9;
}

/* Responsive tweak */
@media (max-width: 768px) {
    .work-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }

    .work-card img {
        height: 200px;
    }
}





/* ====== PUBLICATION CARDS ====== */
.publication-card {
    display: flex;
    background: var(--white);
    border-radius: var(--border-radius-lg);
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: var(--shadow-card);
    transition: var(--transition);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.publication-card::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--gradient-primary);
    transform: scaleX(0);
    transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.publication-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
}

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

.pub-image {
    width: 180px;
    height: auto;
    border-radius: var(--border-radius);
    margin-right: 30px;
    object-fit: cover;
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.publication-card:hover .pub-image {
    transform: scale(1.05);
}

.apa-style {
    font-size: 1.05rem;
    line-height: 1.8;
    text-align: justify;
    color: var(--text-color);
}

.apa-style .journal-title {
    font-style: italic;
    color: var(--primary-color);
}

.apa-style .author-highlight {
    background: linear-gradient(135deg, rgba(0,123,255,0.1), rgba(74,171,247,0.1));
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 600;
}

.apa-style a {
    color: var(--primary-color);
    text-decoration: none;
    position: relative;
    font-weight: 600;
    transition: var(--transition);
}

.apa-style a::after {
    content: "";
    position: absolute;
    width: 0;
    height: 2px;
    bottom: -2px;
    left: 0;
    background: var(--gradient-primary);
    transition: width 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.apa-style a:hover {
    color: var(--primary-dark);
}

.apa-style a:hover::after {
    width: 100%;
}

/* ====== FOOTER ====== */
footer {
    background: linear-gradient(135deg, var(--secondary-color) 0%, #34495e 100%);
    color: var(--white);
    text-align: center;
    padding: 40px 0;
    margin-top: 80px;
    position: relative;
}

footer::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--gradient-primary);
}

footer p {
    font-size: 1rem;
    opacity: 0.9;
    font-weight: 500;
}

/* ====== RESPONSIVE DESIGN ====== */
@media (max-width: 1024px) {
    :root {
        --max-width: 960px;
    }
    
    .research-grid,
    .work-grid {
        grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
        gap: 30px;
    }
}

@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }
    
    nav ul {
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(20px) saturate(180%);
        flex-direction: column;
        justify-content: flex-start;
        align-items: flex-start;
        padding: 100px 30px 30px;
        transition: right 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
        box-shadow: -5px 0 25px rgba(0,0,0,0.1);
        gap: 0;
    }
    
    nav ul.active {
        right: 0;
    }
    
    nav ul li {
        width: 100%;
        margin-bottom: 5px;
    }
    
    nav ul li a {
        padding: 15px 20px;
        font-size: 1.1rem;
        font-weight: 500; /* Keep normal weight in mobile */
        border-radius: var(--border-radius);
        width: 100%;
        transition: var(--transition);
    }
    
    /* Active state in mobile - still bold */
    nav ul li a.active {
        font-weight: 700;
        color: var(--primary-color);
    }
    
    nav ul li a:hover {
        background: linear-gradient(135deg, var(--primary-color), var(--primary-light));
        color: var(--white);
        transform: translateX(5px);
    }
    
    nav ul li a::after {
        display: none;
    }
    
    .dropdown-content {
        position: static;
        opacity: 1;
        visibility: visible;
        transform: none;
        box-shadow: none;
        background: var(--light-gray);
        margin: 5px 0 10px 20px;
        border-radius: var(--border-radius);
    }
    
    .dropdown-content a {
        padding: 10px 15px;
        font-size: 0.95rem;
        font-weight: 500; /* Keep normal weight for dropdown in mobile */
    }
    
    .container {
        padding: 0 15px;
    }
    
    header .container {
        padding: 15px;
    }
    
    .logo {
        font-size: 1.6rem;
    }
    
    .hero {
        height: 70vh;
        min-height: 500px;
    }
    
    .hero-text {
        padding: 40px 30px;
        margin: 0 15px;
    }
    
    .profile {
        padding: 50px 30px;
        margin-top: -40px;
    }
    
    .research-area,
    .recent-work {
        padding: 80px 0;
    }
    
    .research-grid,
    .work-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }
    
    .research-card {
        padding: 40px 25px;
    }
    
    .work-content {
        padding: 25px;
    }
    
    .publication-card {
        flex-direction: column;
        padding: 25px;
    }
    
    .pub-image {
        width: 100%;
        height: 200px;
        margin-right: 0;
        margin-bottom: 20px;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 1.4rem;
    }
    
    .hero-text h1 {
        font-size: 2.2rem;
    }
    
    .hero-text p {
        font-size: 1.1rem;
    }
    
    .profile h2,
    .research-area h2,
    .recent-work h2 {
        font-size: 2rem;
    }
    
    nav ul {
        width: 100%;
        right: -100%;
    }
    
    .research-card,
    .work-content,
    .publication-card {
        padding: 20px;
    }
}

/* ====== ACCESSIBILITY ====== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* ====== FOCUS STYLES ====== */
a:focus,
button:focus {
    outline: 3px solid var(--primary-color);
    outline-offset: 2px;
    border-radius: 4px;
}

/* ====== PRINT STYLES ====== */
@media print {
    header,
    footer,
    .hero,
    .hamburger {
        display: none;
    }
    
    body {
        background: white;
        color: black;
    }
    
    .container {
        width: 100%;
        max-width: none;
    }
    
    .profile,
    .research-card,
    .work-card,
    .publication-card {
        box-shadow: none;
        border: 1px solid #ccc;
    }
}




/* ====== LOADING ANIMATION ====== */
.loading {
    opacity: 0;
    animation: fadeIn 0.6s ease forwards;
}

@keyframes fadeIn {
    to {
        opacity: 1;
    }
}




/* ====== ALIH BAHASA ====== */
.lang-switch {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
}

.lang-switch a {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 3px 8px;
    border-radius: 8px;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.2s ease;
}

.lang-switch a:hover {
    background: var(--background-light);
    color: var(--primary-color);
}

.lang-switch a.active {
    font-weight: 600;
    color: var(--primary-color);
    background: rgba(37, 99, 235, 0.1);
}




/* ====== SCROLL TO TOP ====== */
.scroll-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--gradient-primary);
    color: var(--white);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-top:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
}