/* VARIABEL DAN DARK MODE DEFAULT */
:root {
    --primary-bg: #0a0a14;
    --secondary-bg: #121220;
    --card-bg: #1a1a2e;
    --text-primary: #f0f0f5;
    --text-secondary: #a0a0b0;
    --accent: #8a2b3d;
    --accent-light: #a34055;
    --success: #2e8b57;
    --transition: all 0.4s ease;
    --shadow: 0 5px 15px rgba(0, 0, 0, 0.4);
    --blur: blur(10px);
}

/* DARK MODE */
[data-theme="light"] {
    --primary-bg: #f0f2f5;
    --secondary-bg: #e4e6eb;
    --card-bg: #ffffff;
    --text-primary: #1a1a2e;
    --text-secondary: #4a4a5a;
    --accent: #8a2b3d;
    --accent-light: #a34055;
    --shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

/* RESET & BASE STYLES */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

html {
    scroll-behavior: smooth;
}

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

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

section {
    padding: 100px 0;
    position: relative;
}

h1,
h2,
h3,
h4 {
    line-height: 1.2;
    margin-bottom: 20px;
    font-weight: 700;
}

h1 {
    font-size: 3.5rem;
}

h2 {
    font-size: 2.5rem;
    position: relative;
    display: inline-block;
    margin-bottom: 60px;
}

h2:after {
    content: "";
    position: absolute;
    bottom: -15px;
    left: 0;
    width: 80px;
    height: 4px;
    background: var(--accent);
    border-radius: 2px;
}

p {
    margin-bottom: 15px;
    color: var(--text-secondary);
}

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

a:hover {
    color: var(--accent-light);
}

.btn {
    display: inline-block;
    background: var(--accent);
    color: white;
    padding: 12px 28px;
    border-radius: 30px;
    font-weight: 600;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    font-size: 1rem;
    box-shadow: var(--shadow);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn:hover {
    background: var(--accent-light);
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(138, 43, 61, 0.3);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--accent);
    color: var(--accent);
}

.btn-outline:hover {
    background: var(--accent);
    color: white;
}

/* CUSTOM CURSOR */
.cursor {
    position: fixed;
    width: 20px;
    height: 20px;
    border: 2px solid var(--accent);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
    z-index: 9999;
    transition:
        transform 0.2s,
        width 0.2s,
        height 0.2s;
    mix-blend-mode: difference;
}

.cursor-follower {
    position: fixed;
    width: 8px;
    height: 8px;
    background: var(--accent);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    pointer-events: none;
    z-index: 9998;
    transition:
        width 0.3s,
        height 0.3s;
    mix-blend-mode: difference;
}

.cursor-follower.hover,
.cursor.hover {
    transform: translate(-50%, -50%) scale(1.5);
    background: var(--accent);
}

/* NAVBAR */
nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    padding: 20px 0;
    z-index: 1000;
    transition: var(--transition);
    backdrop-filter: var(--blur);
    background: rgba(10, 10, 20, 0.8);
}

[data-theme="light"] nav {
    background: rgba(240, 242, 245, 0.8);
}

nav.scrolled {
    padding: 15px 0;
    box-shadow: var(--shadow);
}

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

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
}

.logo span {
    color: var(--accent);
}

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

.nav-links li {
    margin-left: 30px;
}

.nav-links a {
    color: var(--text-primary);
    font-weight: 500;
    position: relative;
    padding: 5px 0;
}

.nav-links a:after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width 0.3s ease;
}

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

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
    margin-left: 20px;
    transition: var(--transition);
}

.theme-toggle:hover {
    color: var(--accent);
    transform: rotate(20deg);
}

.menu-btn {
    display: none;
    font-size: 1.5rem;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
}

/* HERO SECTION */
#hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding-top: 80px;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 600px;
}

.hero-subtitle {
    color: var(--accent);
    font-weight: 600;
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-size: 1.1rem;
}

.hero-title {
    font-size: 4rem;
    margin-bottom: 20px;
    line-height: 1.1;
}

.hero-desc {
    font-size: 1.2rem;
    margin-bottom: 30px;
}

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

.profile-img {
    position: absolute;
    right: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 400px;
    height: 400px;
    border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.8s ease;
    z-index: 1;
}

.profile-img:hover {
    border-radius: 50%;
    transform: translateY(-50%) scale(1.05);
}

.profile-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* PARTICLE BACKGROUND */
#particles-js {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: 0;
}

/* ABOUT SECTION */
#about {
    background: var(--secondary-bg);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-text h2 {
    margin-bottom: 30px;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin-top: 30px;
}

.stat-box {
    background: var(--card-bg);
    padding: 25px;
    border-radius: 10px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.stat-box i {
    font-size: 2.5rem;
    color: var(--accent);
    margin-bottom: 15px;
}

.stat-box h3 {
    font-size: 2rem;
    margin-bottom: 5px;
}

/* SKILLS SECTION */
.skills-container {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.skill-category h3 {
    margin-bottom: 25px;
    color: var(--accent);
}

.skill-item {
    margin-bottom: 25px;
}

.skill-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
}

.skill-bar {
    height: 10px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 5px;
    overflow: hidden;
}

.skill-progress {
    height: 100%;
    background: var(--accent);
    border-radius: 5px;
    width: 0;
    transition: width 1.5s ease;
}

/* PORTFOLIO SECTION */
#portfolio {
    background: var(--secondary-bg);
}

.portfolio-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 40px;
}

.portfolio-filters {
    display: flex;
    gap: 15px;
    flex-wrap: wrap;
}

.filter-btn {
    background: var(--card-bg);
    color: var(--text-secondary);
    border: none;
    padding: 8px 20px;
    border-radius: 30px;
    cursor: pointer;
    transition: var(--transition);
}

.filter-btn.active,
.filter-btn:hover {
    background: var(--accent);
    color: white;
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.portfolio-item {
    background: var(--card-bg);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    opacity: 0;
    transform: translateY(30px);
}

.portfolio-item.visible {
    opacity: 1;
    transform: translateY(0);
}

.portfolio-item:hover {
    transform: translateY(-10px);
}

.portfolio-img {
    height: 200px;
    overflow: hidden;
}

.portfolio-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.portfolio-item:hover .portfolio-img img {
    transform: scale(1.1);
}

.portfolio-info {
    padding: 25px;
}

.portfolio-info h3 {
    margin-bottom: 10px;
}

.portfolio-category {
    color: var(--accent);
    font-weight: 600;
    font-size: 0.9rem;
    margin-bottom: 15px;
    display: block;
}

/* tech section */
#tech {
    background: var(--primary-bg);
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.tech-card {
    background: var(--card-bg);
    border-radius: 10px;
    padding: 40px 30px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.tech-card:hover {
    transform: translateY(-10px);
}

.tech-card i {
    font-size: 3.5rem;
    color: var(--accent);
    margin-bottom: 20px;
}

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

.tech-card .nixos-icon {
    width: 3.5rem;
    height: 3.5rem;
    display: block;
    margin: 0 auto 20px;
    color: var(--accent);
}

.tech-card .kotlin-icon {
    width: 3.5rem;
    height: 3.5rem;
    display: block;
    margin: 0 auto 20px;
    color: var(--accent);
}

.tech-card .jupyter-icon {
    width: 3.5rem;
    height: 3.5rem;
    display: block;
    margin: 0 auto 20px;
    color: var(--accent);
}

/* CONTACT SECTION */
#contact {
    background: var(--secondary-bg);
}

.contact-container {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 50px;
}

.contact-info h3 {
    margin-bottom: 30px;
}

.contact-item {
    display: flex;
    gap: 20px;
    margin-bottom: 30px;
    align-items: flex-start;
}

.contact-icon {
    width: 60px;
    height: 60px;
    background: var(--accent);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    flex-shrink: 0;
}

.contact-form .form-group {
    margin-bottom: 25px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 15px;
    background: var(--card-bg);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 5px;
    color: var(--text-primary);
    font-size: 1rem;
    transition: var(--transition);
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--accent);
    outline: none;
}

.contact-form textarea {
    min-height: 150px;
    resize: vertical;
}

.form-error {
    color: #ff6b6b;
    font-size: 0.9rem;
    margin-top: 5px;
    display: none;
}

/* FOOTER */
footer {
    padding: 60px 0 30px;
    text-align: center;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 30px;
}

.social-link {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: var(--card-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    transition: var(--transition);
    color: var(--text-primary);
}

.social-link:hover {
    background: var(--accent);
    transform: translateY(-5px);
}

.copyright {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* BACK TO TOP BUTTON */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--accent);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 100;
    box-shadow: var(--shadow);
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--accent-light);
    transform: translateY(-5px);
}

/* MOBILE MENU */
.mobile-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 300px;
    height: 100%;
    background: var(--card-bg);
    z-index: 2000;
    padding: 80px 30px 30px;
    transition: right 0.4s ease;
    box-shadow: -5px 0 15px rgba(0, 0, 0, 0.2);
}

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

.mobile-links {
    list-style: none;
}

.mobile-links li {
    margin-bottom: 20px;
}

.mobile-links a {
    color: var(--text-primary);
    font-size: 1.2rem;
    font-weight: 500;
    display: block;
    padding: 10px 0;
}

.mobile-links a.active {
    color: var(--accent);
}

.close-menu {
    position: absolute;
    top: 25px;
    right: 25px;
    font-size: 1.5rem;
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
}

/* RESPONSIVE DESIGN */
@media (max-width: 992px) {
    .hero-content {
        max-width: 100%;
        text-align: center;
    }

    .hero-btns {
        justify-content: center;
    }

    .profile-img {
        position: relative;
        margin: 50px auto 0;
        transform: none;
        top: 0;
        width: 300px;
        height: 300px;
    }

    .about-content,
    .contact-container,
    .skills-container {
        grid-template-columns: 1fr;
    }

    .about-stats {
        grid-template-columns: 1fr;
    }

    .portfolio-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .portfolio-filters {
        margin-top: 20px;
    }

    .testimonial-slide {
        padding: 30px 20px;
    }
}

@media (max-width: 768px) {
    h1 {
        font-size: 2.8rem;
    }

    h2 {
        font-size: 2rem;
    }

    .hero-title {
        font-size: 3rem;
    }

    .menu-btn {
        display: block;
    }

    .nav-links {
        display: none;
    }

    .blog-grid,
    .portfolio-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 576px) {
    section {
        padding: 70px 0;
    }

    .hero-btns {
        flex-direction: column;
        gap: 15px;
    }

    .btn {
        width: 100%;
        text-align: center;
    }
}