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

:root {
    /* Color Palette */
    --primary-color: #1a1a2e;
    --secondary-color: #16213e;
    --accent-color: #0f3460;
    --highlight-color: #e94560;
    --gold-color: #f39c12;
    --text-light: #ffffff;
    --text-gray: #b8b8b8;
    --text-dark: #333333;
    --bg-dark: #0a0a0a;
    --bg-light: #f8f9fa;
    
    /* Typography */
    --font-primary: 'Montserrat', sans-serif;
    --font-secondary: 'Poppins', sans-serif;
    
    /* Spacing */
    --section-padding: 100px 0;
    --container-padding: 0 20px;
    
    /* Transitions */
    --transition-fast: 0.3s ease;
    --transition-medium: 0.5s ease;
    --transition-slow: 0.8s ease;
    
    /* Shadows */
    --shadow-light: 0 5px 15px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 10px 30px rgba(0, 0, 0, 0.2);
    --shadow-heavy: 0 20px 60px rgba(0, 0, 0, 0.3);
    
    /* Border Radius */
    --border-radius: 12px;
    --border-radius-large: 20px;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    overflow-x: hidden;
}

body {
    font-family: var(--font-secondary);
    overflow-x: hidden;
    min-width: 320px;
    line-height: 1.6;
    color: var(--text-light);
    background: var(--bg-dark);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--container-padding);
    width: 100%;
}

/* ===== UTILITY CLASSES ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 15px 30px;
    border: none;
    border-radius: var(--border-radius);
    font-family: var(--font-primary);
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left var(--transition-medium);
    z-index: -1;
}

.btn:hover::before {
    left: 100%;
}

.btn-primary {
    background: linear-gradient(135deg, var(--highlight-color), var(--gold-color));
    color: var(--text-light);
    box-shadow: var(--shadow-medium);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-heavy);
}

.btn-secondary {
    background: transparent;
    color: var(--text-light);
    border: 2px solid var(--highlight-color);
}

.btn-secondary:hover {
    background: var(--highlight-color);
    transform: translateY(-3px);
}

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

.btn-outline:hover {
    background: var(--gold-color);
    color: var(--text-dark);
}

/* ===== SECTION HEADERS ===== */
.section-header {
    text-align: center;
    margin-bottom: 80px;
}

.section-title {
    font-family: var(--font-primary);
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-light);
    margin-bottom: 20px;
    position: relative;
    display: inline-block;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--highlight-color), var(--gold-color));
    border-radius: 2px;
}

.section-subtitle {
    font-size: 1.2rem;
    color: var(--text-gray);
    max-width: 600px;
    margin: 0 auto;
}

/* ===== ANIMATIONS ===== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(50px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.8);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-20px);
    }
}

@keyframes pulse {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
}

@keyframes gradient {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

/* ===== NAVIGATION ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(26, 26, 46, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    transition: all var(--transition-fast);
    padding: 15px 0;
}

.navbar.scrolled {
    background: rgba(26, 26, 46, 0.98);
    box-shadow: var(--shadow-medium);
    padding: 10px 0;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo-link {
    text-decoration: none;
}

.logo-text {
    font-family: var(--font-primary);
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--highlight-color), var(--gold-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-list {
    display: flex;
    list-style: none;
    gap: 40px;
}

.nav-link {
    color: var(--text-light);
    text-decoration: none;
    font-weight: 500;
    position: relative;
    transition: color var(--transition-fast);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--highlight-color), var(--gold-color));
    transition: width var(--transition-fast);
}

.nav-link:hover {
    color: var(--gold-color);
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 4px;
}

.bar {
    width: 25px;
    height: 3px;
    background: var(--text-light);
    transition: all var(--transition-fast);
    border-radius: 2px;
}

/* ===== HERO SECTION ===== */
.hero {
    height: 100vh;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color), var(--accent-color));
    background-size: 400% 400%;
    animation: gradient 15s ease infinite;
}

.gradient-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, transparent 0%, rgba(0, 0, 0, 0.3) 100%);
}

.particles {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

.particle {
    position: absolute;
    background: var(--gold-color);
    border-radius: 50%;
    opacity: 0.6;
    animation: float 6s ease-in-out infinite;
}

.hero-content {
    text-align: center;
    z-index: 2;
    max-width: 800px;
    padding: 0 20px;
}

.hero-title {
    font-family: var(--font-primary);
    font-size: 4rem;
    font-weight: 800;
    margin-bottom: 30px;
    line-height: 1.2;
}

.greeting {
    display: block;
    font-size: 1.5rem;
    font-weight: 400;
    color: var(--text-gray);
    margin-bottom: 10px;
    animation: fadeInUp 1s ease 0.2s both;
}

.name {
    display: block;
    background: linear-gradient(135deg, var(--highlight-color), var(--gold-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: fadeInUp 1s ease 0.4s both;
}

.hero-subtitle {
    font-size: 1.3rem;
    color: var(--text-gray);
    margin-bottom: 40px;
    animation: fadeInUp 1s ease 0.6s both;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 1s ease 0.8s both;
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    animation: float 3s ease-in-out infinite;
}

.scroll-arrow {
    color: var(--text-gray);
    font-size: 1.5rem;
    cursor: pointer;
    transition: color var(--transition-fast);
}

.scroll-arrow:hover {
    color: var(--gold-color);
}

/* ===== ABOUT SECTION ===== */
.about {
    padding: var(--section-padding);
    background: var(--bg-dark);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 80px;
    align-items: center;
}

.about-image {
    position: relative;
}

.image-container {
    position: relative;
    width: 350px;
    height: 350px;
    margin: 0 auto;
}

.profile-img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: var(--border-radius-large);
    position: relative;
    z-index: 2;
}

.image-border {
    position: absolute;
    top: -20px;
    left: -20px;
    width: calc(100% + 40px);
    height: calc(100% + 40px);
    border: 3px solid var(--gold-color);
    border-radius: var(--border-radius-large);
    z-index: 1;
    animation: pulse 3s ease-in-out infinite;
}

.about-title {
    font-family: var(--font-primary);
    font-size: 2.2rem;
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 20px;
}

.about-description {
    font-size: 1.1rem;
    color: var(--text-gray);
    margin-bottom: 40px;
    line-height: 1.8;
}

.about-details {
    margin-bottom: 40px;
}

.detail-item {
    display: flex;
    align-items: flex-start;
    gap: 20px;
    margin-bottom: 25px;
}

.detail-item i {
    color: var(--gold-color);
    font-size: 1.3rem;
    margin-top: 5px;
}

.detail-content h4 {
    font-family: var(--font-primary);
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 5px;
}

.detail-content p {
    color: var(--text-gray);
    margin-bottom: 5px;
}

.detail-year {
    color: var(--gold-color);
    font-size: 0.9rem;
    font-weight: 500;
}

.about-buttons {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
}

/* ===== SKILLS SECTION ===== */
.skills {
    padding: var(--section-padding);
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
}

.skills-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 40px;
}

.skill-category {
    background: rgba(255, 255, 255, 0.05);
    padding: 40px;
    border-radius: var(--border-radius-large);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.category-header {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 40px;
}

.category-header i {
    font-size: 2rem;
    color: var(--gold-color);
}

.category-header h3 {
    font-family: var(--font-primary);
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--text-light);
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.skill-item {
    background: rgba(255, 255, 255, 0.05);
    padding: 20px;
    border-radius: var(--border-radius);
    text-align: center;
    transition: all var(--transition-fast);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.skill-item:hover {
    transform: translateY(-10px);
    background: rgba(255, 255, 255, 0.1);
    box-shadow: var(--shadow-medium);
}

.skill-icon {
    font-size: 2.2rem;
    color: var(--gold-color);
    margin-bottom: 15px;
}

.skill-item h4 {
    font-family: var(--font-primary);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 0;
    line-height: 1.4;
}

/* ===== CERTIFICATES SECTION ===== */
.certificates {
    padding: var(--section-padding);
    background: linear-gradient(135deg, var(--secondary-color), var(--primary-color));
}

.certificates-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(500px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

.certificate-card {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius-large);
    overflow: hidden;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all var(--transition-smooth);
    position: relative;
}

.certificate-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-large);
    border-color: rgba(243, 156, 18, 0.3);
}

.certificate-image {
    position: relative;
    height: 300px;
    overflow: hidden;
}

.certificate-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-smooth);
}

.certificate-card:hover .certificate-image img {
    transform: scale(1.05);
}

.certificate-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(45deg, rgba(0, 0, 0, 0.3), rgba(243, 156, 18, 0.2));
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity var(--transition-smooth);
}

.certificate-card:hover .certificate-overlay {
    opacity: 1;
}

.certificate-badge {
    width: 80px;
    height: 80px;
    background: var(--gold-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    color: var(--text-dark);
    transform: scale(0);
    transition: transform var(--transition-smooth);
}

.certificate-card:hover .certificate-badge {
    transform: scale(1);
}

.certificate-content {
    padding: 30px;
}

.certificate-title {
    font-family: var(--font-primary);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-light);
    margin-bottom: 15px;
    line-height: 1.3;
}

.certificate-issuer {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
    color: var(--gold-color);
    font-weight: 500;
}

.certificate-issuer i {
    font-size: 1.1rem;
}

.certificate-description {
    color: var(--text-gray);
    line-height: 1.6;
    margin-bottom: 25px;
    font-size: 0.95rem;
}

.certificate-details {
    display: flex;
    gap: 30px;
    flex-wrap: wrap;
}

.certificate-duration,
.certificate-date {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-light);
    font-size: 0.9rem;
    font-weight: 500;
}

.certificate-duration i,
.certificate-date i {
    color: var(--gold-color);
    font-size: 1rem;
}

/* ===== PROJECTS SECTION ===== */
.projects {
    padding: var(--section-padding);
    background: var(--bg-dark);
}

.projects-filter {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 60px;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 12px 25px;
    background: transparent;
    color: var(--text-gray);
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius);
    font-family: var(--font-primary);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.filter-btn:hover,
.filter-btn.active {
    color: var(--text-light);
    border-color: var(--gold-color);
    background: rgba(243, 156, 18, 0.1);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
}

.project-card {
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius-large);
    overflow: hidden;
    transition: all var(--transition-fast);
    border: 1px solid rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
}

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

.project-image {
    position: relative;
    height: 250px;
    overflow: hidden;
}

.project-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-medium);
}

.project-card:hover .project-image img {
    transform: scale(1.1);
}

.project-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.project-card:hover .project-overlay {
    opacity: 1;
}

.project-links {
    display: flex;
    gap: 20px;
}

.project-link {
    width: 50px;
    height: 50px;
    background: var(--gold-color);
    color: var(--text-dark);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    text-decoration: none;
    font-size: 1.2rem;
    transition: all var(--transition-fast);
}

.project-link:hover {
    background: var(--highlight-color);
    color: var(--text-light);
    transform: scale(1.1);
}

.project-content {
    padding: 30px;
}

.project-title {
    font-family: var(--font-primary);
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 15px;
}

.project-description {
    color: var(--text-gray);
    margin-bottom: 20px;
    line-height: 1.6;
}

.project-tech {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.tech-tag {
    padding: 5px 12px;
    background: rgba(243, 156, 18, 0.2);
    color: var(--gold-color);
    border-radius: 15px;
    font-size: 0.85rem;
    font-weight: 500;
}

/* ===== EXPERIENCE SECTION ===== */
.experience {
    padding: var(--section-padding);
    background: var(--primary-color);
    position: relative;
}

.experience-content {
    max-width: 800px;
    margin: 0 auto;
    margin-top: 60px;
}

.experience-item {
    background: rgba(255, 255, 255, 0.05);
    padding: 40px;
    border-radius: var(--border-radius-large);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    position: relative;
    overflow: hidden;
}

.experience-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(135deg, var(--gold-color), var(--highlight-color));
}

.experience-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 30px;
    flex-wrap: wrap;
    gap: 20px;
}

.experience-title h3 {
    font-family: var(--font-primary);
    font-size: 1.8rem;
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 10px;
}

.company-location {
    display: flex;
    align-items: center;
    gap: 20px;
    flex-wrap: wrap;
}

.company {
    font-size: 1.1rem;
    color: var(--gold-color);
    font-weight: 500;
}

.location {
    display: flex;
    align-items: center;
    gap: 5px;
    color: var(--text-gray);
    font-size: 0.95rem;
}

.experience-duration {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(243, 156, 18, 0.1);
    padding: 8px 16px;
    border-radius: var(--border-radius);
    color: var(--gold-color);
    font-weight: 500;
    white-space: nowrap;
}

.experience-duration i {
    font-size: 0.9rem;
}

.experience-description {
    margin-top: 20px;
}

.experience-list {
    list-style: none;
    padding: 0;
}

.experience-list li {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    margin-bottom: 20px;
    color: var(--text-gray);
    line-height: 1.6;
}

.experience-list li:last-child {
    margin-bottom: 0;
}

.experience-list li i {
    color: var(--gold-color);
    font-size: 0.9rem;
    margin-top: 4px;
    flex-shrink: 0;
}

/* ===== CONTACT SECTION ===== */
.contact {
    padding: var(--section-padding);
    background: linear-gradient(135deg, var(--secondary-color), var(--accent-color));
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    align-items: start;
}

.contact-item {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 40px;
}

.contact-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--highlight-color), var(--gold-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--text-light);
}

.contact-details h4 {
    font-family: var(--font-primary);
    font-weight: 600;
    color: var(--text-light);
    margin-bottom: 5px;
}

.contact-details p {
    color: var(--text-gray);
}

.contact-link {
    color: var(--text-gray);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.contact-link:hover {
    color: var(--gold-color);
}

.social-links {
    display: flex;
    gap: 20px;
    margin-top: 40px;
}

.social-link {
    width: 50px;
    height: 50px;
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-light);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    text-decoration: none;
    font-size: 1.3rem;
    transition: all var(--transition-fast);
    border: 2px solid transparent;
}

.social-link:hover {
    background: var(--gold-color);
    color: var(--text-dark);
    transform: translateY(-3px);
    border-color: var(--gold-color);
}

.contact-form {
    background: rgba(255, 255, 255, 0.05);
    padding: 40px;
    border-radius: var(--border-radius-large);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.form-group {
    position: relative;
    margin-bottom: 30px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 15px 0;
    background: transparent;
    border: none;
    border-bottom: 2px solid rgba(255, 255, 255, 0.3);
    color: var(--text-light);
    font-size: 1rem;
    outline: none;
    transition: all var(--transition-fast);
}

.form-group label {
    position: absolute;
    top: 15px;
    left: 0;
    color: var(--text-gray);
    font-size: 1rem;
    pointer-events: none;
    transition: all var(--transition-fast);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group input:valid,
.form-group textarea:valid {
    border-bottom-color: var(--gold-color);
}

.form-group input:focus + label,
.form-group textarea:focus + label,
.form-group input:valid + label,
.form-group textarea:valid + label {
    top: -10px;
    font-size: 0.85rem;
    color: var(--gold-color);
}

.form-line {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--highlight-color), var(--gold-color));
    transition: width var(--transition-fast);
}

.form-group input:focus ~ .form-line,
.form-group textarea:focus ~ .form-line {
    width: 100%;
}

/* ===== FOOTER ===== */
.footer {
    background: var(--primary-color);
    padding: 40px 0;
    position: relative;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-text p {
    color: var(--text-gray);
}

.footer-links {
    display: flex;
    gap: 30px;
    flex-wrap: wrap;
}

.footer-links a {
    color: var(--text-gray);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--gold-color);
}

.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--highlight-color), var(--gold-color));
    color: var(--text-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    z-index: 1000;
}

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

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

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 1024px) {
    .hero-title {
        font-size: 3rem;
    }
    
    .about-content {
        grid-template-columns: 1fr;
        gap: 60px;
        text-align: center;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 60px;
    }
    
    .certificates-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .image-container {
        width: 300px;
        height: 300px;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: rgba(26, 26, 46, 0.98);
        backdrop-filter: blur(10px);
        transition: left var(--transition-fast);
        padding: 50px 0;
    }
    
    .nav-menu.active {
        left: 0;
    }
    
    .nav-list {
        flex-direction: column;
        align-items: center;
        gap: 30px;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .nav-toggle.active .bar:nth-child(1) {
        transform: rotate(45deg) translate(5px, 5px);
    }
    
    .nav-toggle.active .bar:nth-child(2) {
        opacity: 0;
    }
    
    .nav-toggle.active .bar:nth-child(3) {
        transform: rotate(-45deg) translate(7px, -6px);
    }
    
    .skills-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }
    
    .skill-category {
        padding: 30px 20px;
    }
    
    .category-header {
        gap: 15px;
        margin-bottom: 30px;
    }
    
    .category-header i {
        font-size: 1.5rem;
    }
    
    .category-header h3 {
        font-size: 1.5rem;
    }
    
    .skills-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        gap: 15px;
    }
    
    .skill-item {
        padding: 15px 10px;
    }
    
    .skill-item h4 {
        font-size: 0.9rem;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .section-title {
        font-size: 2.5rem;
    }
    
    .projects-grid {
        grid-template-columns: 1fr;
    }
    
    .skills-grid {
        grid-template-columns: 1fr;
    }
    
    .about-buttons {
        justify-content: center;
    }
}

@media (max-width: 480px) {
    :root {
        --section-padding: 60px 0;
        --container-padding: 0 15px;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
    
    .btn {
        padding: 12px 20px;
        font-size: 0.9rem;
    }
    
    .image-container {
        width: 250px;
        height: 250px;
    }
    
    .projects-filter {
        gap: 10px;
    }
    
    .filter-btn {
        padding: 8px 15px;
        font-size: 0.9rem;
    }
    
    .contact-form {
        padding: 30px 20px;
    }
    
    .certificates-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .certificate-card {
        margin: 0 10px;
    }
    
    .certificate-image {
        height: 250px;
    }
    
    .certificate-content {
        padding: 20px;
    }
    
    .certificate-title {
        font-size: 1.3rem;
    }
    
    .certificate-details {
        gap: 20px;
    }
}

/* ===== SCROLL ANIMATIONS ===== */
.fade-in {
    opacity: 1;
    transform: translateY(0);
    transition: all 0.8s ease;
}

.fade-in.animate {
    opacity: 0;
    transform: translateY(50px);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

.slide-in-left {
    opacity: 1;
    transform: translateX(0);
    transition: all 0.8s ease;
}

.slide-in-left.animate {
    opacity: 0;
    transform: translateX(-50px);
}

.slide-in-left.visible {
    opacity: 1;
    transform: translateX(0);
}

.slide-in-right {
    opacity: 1;
    transform: translateX(0);
    transition: all 0.8s ease;
}

.slide-in-right.animate {
    opacity: 0;
    transform: translateX(50px);
}

.slide-in-right.visible {
    opacity: 1;
    transform: translateX(0);
}

.scale-in {
    opacity: 1;
    transform: scale(1);
    transition: all 0.8s ease;
}

.scale-in.animate {
    opacity: 0;
    transform: scale(0.8);
}

.scale-in.visible {
    opacity: 1;
    transform: scale(1);
}

/* ===== PROJECT FILTER ANIMATIONS ===== */
.project-card {
    opacity: 1;
    transform: scale(1);
    transition: all 0.5s ease;
    display: block;
}

.project-card.hide {
    display: none;
}

.project-card.show {
    opacity: 1;
    transform: scale(1);
    display: block;
}