/* ==========================================================================
   1. CSS VARIABLES & THEME SETUP
   ========================================================================== */
:root {
    /* Dark Theme (Default) */
    --bg-color: #050505;
    --surface-color: #121212;
    --text-main: #ffffff;
    --text-muted: #a0a0a0;
    --accent-blue: #00d2ff;
    --accent-purple: #9d50bb;
    --glass-bg: rgba(255, 255, 255, 0.03);
    --glass-border: rgba(255, 255, 255, 0.08);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
}

[data-theme="light"] {
    /* Light Theme */
    --bg-color: #f8f9fa;
    --surface-color: #ffffff;
    --text-main: #1a1a1a;
    --text-muted: #555555;
    --accent-blue: #007bff;
    --accent-purple: #6f42c1;
    --glass-bg: rgba(0, 0, 0, 0.03);
    --glass-border: rgba(0, 0, 0, 0.1);
    --glass-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.05);
}

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

html {
    scroll-behavior: smooth;
    scrollbar-width: thin;
    scrollbar-color: var(--accent-purple) var(--bg-color);
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
    transition: background-color 0.4s ease, color 0.4s ease;
    cursor: none; /* Hide default cursor for custom one */
}

h1, h2, h3, h4, h5, h6, .brand-logo {
    font-family: 'Syne', sans-serif;
    font-weight: 700;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* Scrollbar */
::-webkit-scrollbar { width: 8px; }
::-webkit-scrollbar-track { background: var(--bg-color); }
::-webkit-scrollbar-thumb {
    background: linear-gradient(var(--accent-blue), var(--accent-purple));
    border-radius: 10px;
}

/* ==========================================================================
   3. GLOBAL UI COMPONENTS
   ========================================================================== */
/* Custom Cursor */
.cursor-dot, .cursor-outline {
    position: fixed;
    top: 0;
    left: 0;
    transform: translate(-50%, -50%);
    border-radius: 50%;
    z-index: 99999;
    pointer-events: none;
}

.cursor-dot {
    width: 8px;
    height: 8px;
    background-color: var(--accent-blue);
}

.cursor-outline {
    width: 40px;
    height: 40px;
    border: 1px solid var(--accent-purple);
    transition: width 0.2s, height 0.2s, background-color 0.2s;
}

@media (pointer: coarse) {
    body { cursor: auto; }
    .cursor-dot, .cursor-outline { display: none; }
}

/* Scroll Progress */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 4px;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
    z-index: 1000;
    transition: width 0.1s ease;
}

/* Preloader */
#preloader {
    position: fixed;
    inset: 0;
    background: var(--bg-color);
    z-index: 10000;
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    transition: opacity 0.6s ease, visibility 0.6s ease;
}

.loader-logo {
    font-family: 'Syne', sans-serif;
    font-size: 3rem;
    font-weight: 800;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: pulse 1.5s infinite;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 32px;
    border-radius: 30px;
    font-weight: 600;
    font-family: 'Syne', sans-serif;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 0.9rem;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
    overflow: hidden;
    z-index: 1;
    cursor: none;
    border: none;
    outline: none;
}

@media (pointer: coarse) {
    .btn { cursor: pointer; }
}

.btn::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    z-index: -1;
    transition: opacity 0.3s ease;
    opacity: 0;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.btn-primary {
    background: linear-gradient(45deg, var(--accent-blue), var(--accent-purple));
    color: #fff;
    border: 1px solid transparent;
}

.btn-primary::before {
    background: linear-gradient(45deg, var(--accent-purple), var(--accent-blue));
}

.btn-primary:hover::before { opacity: 1; }

.btn-secondary {
    background: transparent;
    color: var(--text-main);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(10px);
}

.btn-secondary:hover {
    background: var(--glass-bg);
    border-color: var(--accent-blue);
}

/* Typography Utilities */
.gradient-text {
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: 3rem;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.section-subtitle {
    color: var(--text-muted);
    font-size: 1.1rem;
    max-width: 600px;
    margin: 0 auto;
}

/* Glass Panel */
.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    box-shadow: var(--glass-shadow);
    padding: 2.5rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
}

.glass-panel:hover {
    transform: translateY(-5px);
    border-color: rgba(0, 210, 255, 0.3);
}

/* Container & Sections */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

section {
    padding: 6rem 0;
    position: relative;
}

/* ==========================================================================
   4. LAYOUT SPECIFICS
   ========================================================================== */
/* Navbar */
nav {
    position: fixed;
    top: 0; left: 0; width: 100%;
    padding: 1.5rem 0;
    z-index: 100;
    transition: background 0.3s ease, padding 0.3s ease;
}

nav.scrolled {
    background: rgba(5, 5, 5, 0.85);
    backdrop-filter: blur(10px);
    padding: 1rem 0;
    border-bottom: 1px solid var(--glass-border);
}

[data-theme="light"] nav.scrolled { background: rgba(248, 249, 250, 0.85); }

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

.logo {
    font-size: 1.8rem;
    font-weight: 800;
    letter-spacing: -1px;
    font-family: 'Syne', sans-serif;
}

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

.nav-links {
    display: flex;
    gap: 2.0rem; 
    flex-wrap: wrap;
}

.nav-links a {
    font-size: 0.95rem;
    font-weight: 500;
    position: relative;
    transition: color 0.3s ease;
}

.nav-links a::after {
    content: '';
    position: absolute;
    width: 0; height: 2px;
    bottom: -5px; left: 0;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
    transition: width 0.3s ease;
}

.nav-links a:hover { color: var(--accent-blue); }
.nav-links a:hover::after { width: 100%; }

.nav-controls {
    display: flex;
    align-items: center;
    gap: 1.5rem;
}

.theme-toggle {
    background: none;
    border: none;
    color: var(--text-main);
    font-size: 1.2rem;
    cursor: pointer;
    transition: color 0.3s ease, transform 0.3s ease;
}
        
.theme-toggle:hover {
    color: var(--accent-blue);
    transform: rotate(15deg);
}

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

/* Hero Section */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    padding-top: 80px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
    overflow: hidden;
}

.hero-bg .orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.4;
    animation: float 15s infinite alternate ease-in-out;
}

.orb-1 {
    width: 400px; height: 400px;
    background: var(--accent-blue);
    top: 10%; left: -10%;
}

.orb-2 {
    width: 500px; height: 500px;
    background: var(--accent-purple);
    bottom: -20%; right: -10%;
    animation-delay: -5s;
}

.hero-content {
    text-align: center;
    position: relative;
    z-index: 1;
    max-width: 900px;
}

.hero-tag {
    display: inline-block;
    padding: 6px 16px;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 2rem;
    backdrop-filter: blur(5px);
    letter-spacing: 1px;
}

.hero h1 {
    font-size: clamp(3rem, 6vw, 5.5rem);
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

.hero p {
    font-size: clamp(1rem, 2vw, 1.3rem);
    color: var(--text-muted);
    margin-bottom: 3rem;
}

.hero-ctas {
    display: flex;
    gap: 1.5rem;
    justify-content: center;
}

/* About Section */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1.25fr;
    gap: 3rem;
    align-items: stretch;
}

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

.skill-bars { margin-top: 2.5rem; }

.skill-item { margin-bottom: 1.5rem; }
        
.skill-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.progress-bg {
    width: 100%;
    height: 8px;
    background: var(--glass-bg);
    border-radius: 4px;
    overflow: hidden;
    border: 1px solid var(--glass-border);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
    width: 0;
    border-radius: 4px;
    transition: width 1.5s cubic-bezier(0.2, 0.8, 0.2, 1);
}

/* Skills/Services Section (Grid) */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr)); 
    gap: 2.5rem;
}

.skill-card {
    text-align: left;
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.skill-icon {
    font-size: 2.5rem;
    margin-bottom: 1.5rem;
    color: var(--accent-blue);
    display: inline-block;
    transition: transform 0.3s ease;
}

.skill-card:hover .skill-icon {
    transform: scale(1.1) rotate(5deg);
}

.skill-card h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
}

.skill-card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* Projects Section */
.projects-filter {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.filter-btn {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    color: var(--text-main);
    padding: 8px 20px;
    border-radius: 20px;
    cursor: pointer;
    font-family: 'Inter', sans-serif;
    font-weight: 500;
    transition: all 0.3s ease;
}

.filter-btn.active, .filter-btn:hover {
    background: var(--accent-blue);
    color: #fff;
    border-color: var(--accent-blue);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2.5rem;
}

.project-card {
    border-radius: 24px;
    overflow: hidden;
    position: relative;
    cursor: pointer;
    border: 1px solid var(--glass-border);
}

.project-img {
    width: 100%;
    height: 250px;
    background-color: var(--surface-color); 
    background-size: cover;
    background-position: center;
    transition: transform 0.6s ease;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Abstract placeholders */
.img-fijs { background: linear-gradient(45deg, #111, #333); }
.img-nsa { background: linear-gradient(45deg, #0f2027, #203a43, #2c5364); }
.img-drone { background: linear-gradient(45deg, #000428, #004e92); }
.img-web { background: linear-gradient(45deg, #141e30, #243b55); }
.img-medai { background: linear-gradient(45deg, #0f2027, #203a43, #2c5364); }
.img-retail { background: linear-gradient(45deg, #11998e, #38ef7d); }
.img-smart { background: linear-gradient(45deg, #4b6cb7, #182848); }
.img-jarvis { background: linear-gradient(45deg, #000000, #434343); }
.img-civic { background: linear-gradient(45deg, #ff9966, #ff5e62); }
.img-skf { background: linear-gradient(45deg, #8E2DE2, #4A00E0); }

.project-img i {
    font-size: 4rem;
    color: rgba(255,255,255,0.2);
}

.project-info {
    position: absolute;
    bottom: 0; left: 0; right: 0;
    padding: 2rem;
    background: linear-gradient(to top, rgba(0,0,0,0.9), transparent);
    transform: translateY(30px);
    opacity: 0;
    transition: all 0.4s ease;
}

.project-card:hover .project-img { transform: scale(1.05); }
.project-card:hover .project-info { transform: translateY(0); opacity: 1; }
        
/* Always show info on touch devices */
@media (pointer: coarse) {
    .project-info { transform: translateY(0); opacity: 1; background: linear-gradient(to top, rgba(0,0,0,0.95) 20%, transparent); }
}

.project-info h3 { margin-bottom: 0.5rem; color: #fff; }
.project-info p { color: #ccc; font-size: 0.9rem; margin-bottom: 1rem; }
.project-tags { display: flex; gap: 0.5rem; flex-wrap: wrap; }
.project-tags span { font-size: 0.75rem; padding: 4px 10px; background: rgba(255,255,255,0.2); backdrop-filter: blur(5px); border-radius: 12px; color: #fff; }

/* Experience & Training Section */
.experience-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); 
    gap: 2rem;
    margin-top: 2rem;
}

.experience-card {
    padding: 2.5rem;
    display: flex;
    flex-direction: column;
    height: 100%;
}
        
.exp-header {
    display: flex;
    align-items: center;
    gap: 1.2rem;
    margin-bottom: 1.5rem;
}

.exp-icon {
    font-size: 2rem;
    color: var(--accent-purple);
    background: rgba(157, 80, 187, 0.1);
    min-width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    transition: all 0.3s ease;
}

.experience-card:hover .exp-icon {
    background: var(--accent-purple);
    color: #fff;
    transform: scale(1.1);
}

/* Achievements / Drone Section */
.achievements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); 
    gap: 2rem;
    margin-top: 2rem;
}

.achievement-card {
    text-align: center;
    padding: 2.5rem 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.achievement-icon {
    font-size: 3rem;
    color: var(--accent-blue);
    margin-bottom: 1.5rem;
    transition: transform 0.3s ease;
}

.achievement-card:hover .achievement-icon {
    transform: translateY(-10px);
    color: var(--accent-purple);
}

/* Milestones & Achievements Section */
.milestone-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); 
    gap: 2rem;
    margin-top: 2rem;
}

.milestone-card {
    text-align: center;
    padding: 3rem 2rem;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    position: relative;
}

.milestone-number {
    font-family: 'Syne', sans-serif;
    font-size: 1.8rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    line-height: 1.2;
}

.milestone-icon {
    font-size: 2.5rem;
    background: linear-gradient(90deg, var(--accent-blue), var(--accent-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 1.5rem;
    display: inline-block;
}

.milestone-text {
    color: var(--text-main);
    font-weight: 600;
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.milestone-subtext {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.5;
}

/* Community & Development Section */
.development-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2.5rem;
}

/* Certifications Section */
.cert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); 
    gap: 2rem;
    margin-top: 2rem;
}

.cert-card {
    padding: 2.5rem 2rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    height: 100%;
}

.cert-header {
    display: flex;
    align-items: center;
    gap: 1.2rem;
    margin-bottom: 0.5rem;
}

.cert-icon {
    font-size: 2rem;
    color: var(--accent-blue);
    background: rgba(0, 210, 255, 0.1);
    min-width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    transition: all 0.3s ease;
}

.cert-card:hover .cert-icon {
    background: var(--accent-blue);
    color: #fff;
    transform: rotate(-10deg);
}

.cert-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-main);
    line-height: 1.3;
}

.cert-issuer {
    color: var(--accent-purple);
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.cert-details {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.5;
}

.cert-meta {
    margin-top: auto;
    padding-top: 1rem;
    border-top: 1px solid var(--glass-border);
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.5);
    display: flex;
    justify-content: space-between;
}

/* Testimonials */
.testimonial-slider {
    display: flex;
    overflow-x: auto;
    scroll-snap-type: x mandatory;
    gap: 2rem;
    padding-bottom: 2rem;
    scrollbar-width: none; 
}
.testimonial-slider::-webkit-scrollbar { display: none; }

.testimonial-card {
    min-width: 300px; 
    width: 85vw;
    max-width: 350px;
    scroll-snap-align: center;
    flex: 0 0 auto;
}

.quote-icon {
    color: var(--accent-purple);
    font-size: 2rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.testimonial-text {
    font-size: 1.1rem;
    font-style: italic;
    margin-bottom: 1.5rem;
}

.client-info { display: flex; align-items: center; gap: 1rem; }
.client-avatar {
    width: 50px; height: 50px;
    border-radius: 50%;
    background: var(--surface-color);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    color: var(--accent-blue);
}
.client-details h4 { font-size: 1rem; margin-bottom: 0.2rem; }
.client-details p { font-size: 0.85rem; color: var(--text-muted); }

/* Contact Section */
.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1.2fr;
    gap: 3rem;
    align-items: stretch;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 0.85rem;
    height: 100%;
}
        
.contact-method {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 1.2rem; 
    padding: 0.85rem 1.2rem; 
    border-radius: 14px; 
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    transition: all 0.3s ease;
}
        
.contact-method:hover {
    border-color: var(--accent-blue);
    transform: translateX(10px);
}

.method-icon {
    width: 42px; height: 42px; 
    border-radius: 50%;
    background: rgba(0, 210, 255, 0.1);
    color: var(--accent-blue);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.2rem;
    flex-shrink: 0;
}

.method-details h4 { font-size: 1rem; margin-bottom: 0.1rem; }
.method-details p { color: var(--text-muted); font-size: 0.85rem; margin: 0; word-break: break-all; }

.contact-form-container.glass-panel {
    align-self: stretch; 
    height: auto;
    display: flex;
    flex-direction: column;
    padding: 2rem;
}

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 1.2rem; 
    height: 100%;
}

.form-group { position: relative; display: flex; flex-direction: column; }
        
.form-group:nth-child(4) { flex: 1; }
        
.form-control {
    width: 100%;
    padding: 1rem 1.5rem;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    color: var(--text-main);
    font-family: 'Inter', sans-serif;
    font-size: 1rem;
    transition: all 0.3s ease;
    outline: none;
}

.form-control:focus {
    border-color: var(--accent-blue);
    box-shadow: 0 0 15px rgba(0, 210, 255, 0.1);
}

textarea.form-control { resize: none; min-height: 120px; height: 100%; }

/* Footer */
footer {
    padding: 3rem 0;
    border-top: 1px solid var(--glass-border);
    text-align: center;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.social-links a {
    width: 45px; height: 45px;
    border-radius: 50%;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    display: flex; align-items: center; justify-content: center;
    font-size: 1.2rem;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: var(--accent-blue);
    color: #fff;
    transform: translateY(-5px);
    border-color: var(--accent-blue);
}

.footer-text { color: var(--text-muted); font-size: 0.9rem; }

/* Modal / Message Box */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    padding: 1rem;
}

.modal-overlay.active {
    opacity: 1; visibility: visible;
}

.modal-content {
    background: var(--surface-color);
    padding: 2.5rem; 
    border-radius: 24px;
    border: 1px solid var(--glass-border);
    text-align: center;
    width: 100%;
    max-width: 400px;
    transform: scale(0.8);
    transition: all 0.3s ease;
    max-height: 90vh;
    overflow-y: auto;
}

.modal-overlay.active .modal-content { transform: scale(1); }
.modal-icon { font-size: 3.5rem; color: var(--accent-blue); margin-bottom: 1rem; }
.modal-close { margin-top: 1.5rem; width: 100%; }

/* Back to top */
.back-to-top {
    position: fixed;
    bottom: 30px; right: 30px;
    width: 50px; height: 50px;
    border-radius: 50%;
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(10px);
    display: flex; align-items: center; justify-content: center;
    color: var(--text-main);
    font-size: 1.2rem;
    z-index: 99;
    opacity: 0; visibility: hidden;
    transition: all 0.3s ease;
    cursor: pointer;
}

.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { background: var(--accent-blue); color: #fff; }

/* WhatsApp Floating Button */
.whatsapp-float {
    position: fixed;
    bottom: 30px;
    left: 30px;
    width: 55px;
    height: 55px;
    background: linear-gradient(45deg, var(--accent-blue), var(--accent-purple));
    color: #FFF;
    border-radius: 50%;
    text-align: center;
    font-size: 28px;
    box-shadow: 0px 4px 20px rgba(0, 210, 255, 0.4);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: all 0.3s ease;
    animation: pulse-wa 2s infinite;
}

.whatsapp-float:hover {
    transform: scale(1.1) rotate(5deg);
    background: linear-gradient(45deg, var(--accent-purple), var(--accent-blue));
    color: #fff;
}

@keyframes pulse-wa {
    0% { box-shadow: 0 0 0 0 rgba(0, 210, 255, 0.6); }
    70% { box-shadow: 0 0 0 15px rgba(0, 210, 255, 0); }
    100% { box-shadow: 0 0 0 0 rgba(0, 210, 255, 0); }
}

/* ==========================================================================
   5. ANIMATIONS & RESPONSIVE MEDIA QUERIES
   ========================================================================== */
@keyframes pulse {
    0% { opacity: 0.5; transform: scale(0.95); }
    50% { opacity: 1; transform: scale(1.05); }
    100% { opacity: 0.5; transform: scale(0.95); }
}

@keyframes float {
    0% { transform: translate(0, 0); }
    100% { transform: translate(30px, 50px); }
}

/* Scroll Reveal Utility Classes */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: all 0.8s cubic-bezier(0.5, 0, 0, 1);
}
        
.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

/* Responsive Design: Tablets */
@media (max-width: 992px) {
    .about-grid, .contact-wrapper, .development-grid { grid-template-columns: 1fr; gap: 3rem; }
    .hero h1 { font-size: 3.8rem; }
    .contact-form-container.glass-panel { padding: 2.5rem; height: auto; }
    .contact-method:hover { transform: translateY(-5px); } 
    .about-visual { min-height: 550px; } 
}

/* Responsive Design: Mobile Phones */
@media (max-width: 768px) {
    section { padding: 4rem 0; }
    .container { padding: 0 1.5rem; }
    .section-header { margin-bottom: 3rem; }
    .section-title { font-size: 2.3rem; }
    .hero h1 { font-size: 3rem; }
    .hero p { font-size: 1.1rem; padding: 0 1rem; }
    
    .hero-ctas { flex-direction: column; width: 100%; max-width: 300px; margin: 0 auto; gap: 1rem; }
    .hero-ctas .btn { width: 100%; }
    .resume-buttons { flex-direction: column; width: 100%; }
    .resume-buttons .btn { width: 100%; }

    .nav-links {
        position: fixed;
        top: 0; right: -100%;
        width: 100%; height: 100vh;
        background: rgba(18, 18, 18, 0.98);
        backdrop-filter: blur(15px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        transition: right 0.4s ease;
        border-left: none;
        gap: 2rem;
    }
    
    [data-theme="light"] .nav-links { background: rgba(255, 255, 255, 0.98); }

    .nav-links.active { right: 0; }
    .nav-links a { font-size: 1.5rem; }
    .mobile-menu-btn { display: block; z-index: 101; }
    
    .projects-filter { flex-wrap: wrap; justify-content: center; gap: 0.5rem; }
    .filter-btn { flex: 1 1 calc(50% - 0.5rem); text-align: center; font-size: 0.9rem; padding: 10px 15px; }
    
    /* On mobile, skills grid drops to single column automatically */
    .skills-grid { grid-template-columns: 1fr; }

    .contact-form-container.glass-panel { padding: 1.5rem; }
    .modal-content { padding: 2rem 1.5rem; }
    
    .back-to-top { bottom: 20px; right: 20px; width: 45px; height: 45px; }
    .whatsapp-float { bottom: 20px; left: 20px; width: 50px; height: 50px; font-size: 24px; }
}

/* Tiny Mobile Screens */
@media (max-width: 480px) {
    .hero h1 { font-size: 2.5rem; }
    .section-title { font-size: 2rem; }
    .about-visual { min-height: 500px; } 
    .project-img { height: 200px; }
    .milestone-card { padding: 2rem 1.5rem; }
    .cert-card { padding: 2rem 1.5rem; }
}