/* ============================================
   CSS Variables & Design System
   ============================================ */
:root {
    /* Dark Theme (Default) */
    --bg-primary: #0a0a0b;
    --bg-secondary: #111113;
    --bg-tertiary: #18181b;
    --bg-card: rgba(24, 24, 27, 0.8);
    --bg-card-hover: rgba(39, 39, 42, 0.9);

    --text-primary: #fafafa;
    --text-secondary: #a1a1aa;
    --text-tertiary: #71717a;

    --border-color: rgba(63, 63, 70, 0.5);
    --border-hover: rgba(113, 113, 122, 0.5);

    --gradient-start: #8b5cf6;
    --gradient-mid: #6366f1;
    --gradient-end: #3b82f6;

    --glow-color: rgba(139, 92, 246, 0.15);
    --glow-strong: rgba(139, 92, 246, 0.3);

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 40px var(--glow-color);

    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 400ms ease;

    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
}

/* Light Theme */
[data-theme="light"] {
    --bg-primary: #ffffff;
    --bg-secondary: #fafafa;
    --bg-tertiary: #f4f4f5;
    --bg-card: rgba(255, 255, 255, 0.9);
    --bg-card-hover: rgba(244, 244, 245, 0.95);

    --text-primary: #18181b;
    --text-secondary: #52525b;
    --text-tertiary: #71717a;

    --border-color: rgba(228, 228, 231, 0.8);
    --border-hover: rgba(161, 161, 170, 0.5);

    --glow-color: rgba(139, 92, 246, 0.1);
    --glow-strong: rgba(139, 92, 246, 0.2);

    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
}

/* ============================================
   Base Styles
   ============================================ */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    transition: background-color var(--transition-base), color var(--transition-base);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

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

/* ============================================
   Layout
   ============================================ */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: 120px 0;
    position: relative;
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-label {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 2px;
    color: var(--gradient-start);
    margin-bottom: 16px;
    text-transform: uppercase;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    font-weight: 600;
    color: var(--text-primary);
    max-width: 700px;
    margin: 0 auto;
    line-height: 1.3;
}

/* ============================================
   Glass Card Effect
   ============================================ */
.glass-card {
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
}

.glass-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    box-shadow: var(--shadow-glow);
    transform: translateY(-2px);
}

/* ============================================
   Navigation
   ============================================ */
.navbar {
    position: fixed;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 100%;
    z-index: 1000;
    padding: 16px 24px;
    background: rgba(10, 10, 11, 0.3);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    transition: top 0.5s cubic-bezier(0.4, 0, 0.2, 1),
        width 0.5s cubic-bezier(0.4, 0, 0.2, 1),
        padding 0.5s cubic-bezier(0.4, 0, 0.2, 1),
        background 0.3s ease,
        border-radius 0.5s cubic-bezier(0.4, 0, 0.2, 1),
        box-shadow 0.3s ease,
        border 0.3s ease;
    border: 1px solid transparent;
    border-radius: 0;
}

[data-theme="light"] .navbar {
    background: rgba(255, 255, 255, 0.3);
}

.navbar.scrolled {
    top: 16px;
    width: calc(100% - 48px);
    max-width: 900px;
    padding: 8px 8px;
    background: rgba(24, 24, 27, 0.5);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(63, 63, 70, 0.4);
    border-radius: var(--radius-xl);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2), 0 0 0 1px rgba(255, 255, 255, 0.05);
}

[data-theme="light"] .navbar.scrolled {
    background: rgba(255, 255, 255, 0.5);
    border: 1px solid rgba(228, 228, 231, 0.5);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1), 0 0 0 1px rgba(0, 0, 0, 0.05);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: padding 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.navbar.scrolled .nav-container {
    padding: 4px 12px;
}

.nav-logo {
    display: flex;
    align-items: center;
}

.logo-text {
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
}

.logo-accent {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 8px;
    list-style: none;
}

.nav-link {
    display: block;
    padding: 10px 16px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-secondary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.nav-link:hover {
    color: var(--text-primary);
    background: var(--bg-tertiary);
}

.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.theme-toggle:hover {
    color: var(--text-primary);
    border-color: var(--border-hover);
    background: var(--bg-card-hover);
}

.theme-toggle .sun-icon {
    display: none;
}

.theme-toggle .moon-icon {
    display: block;
}

[data-theme="light"] .theme-toggle .sun-icon {
    display: block;
}

[data-theme="light"] .theme-toggle .moon-icon {
    display: none;
}

/* Nav Actions - Theme Toggle & Mobile Menu */
.nav-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

/* Mobile Menu */
.mobile-menu-btn {
    display: none;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    padding: 0;
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    cursor: pointer;
}

.hamburger {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    position: relative;
    transition: all var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--text-primary);
    transition: all var(--transition-fast);
}

.hamburger::before {
    top: -7px;
}

.hamburger::after {
    bottom: -7px;
}

.mobile-menu-btn.active .hamburger {
    background: transparent;
}

.mobile-menu-btn.active .hamburger::before {
    transform: rotate(45deg);
    top: 0;
}

.mobile-menu-btn.active .hamburger::after {
    transform: rotate(-45deg);
    bottom: 0;
}

/* ============================================
   Hero Section
   ============================================ */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    padding: 100px 24px 80px;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background:
        radial-gradient(ellipse 80% 50% at 50% -20%, var(--glow-color), transparent),
        radial-gradient(ellipse 60% 40% at 80% 60%, rgba(99, 102, 241, 0.08), transparent),
        radial-gradient(ellipse 50% 30% at 20% 80%, rgba(59, 130, 246, 0.08), transparent);
    pointer-events: none;
    z-index: 1;
}

.hero-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 800px;
    height: 800px;
    background: radial-gradient(circle, var(--glow-color), transparent 70%);
    pointer-events: none;
    opacity: 0.4;
    z-index: 1;
}

/* 3D Spline Container - Fullscreen Background */
.hero-3d-container {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    max-width: 1200px;
    max-height: 900px;
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: splineEntrance 1.2s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes splineEntrance {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0.8);
    }

    100% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1);
    }
}

.hero-3d-container spline-viewer {
    width: 100%;
    height: 100%;
    --spline-viewer-background: transparent;
}

[data-theme="light"] .hero-3d-container {
    opacity: 0.85;
}

/* Bottom Fade Overlay - Hide Robot Legs */
.hero-fade-bottom {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 350px;
    background: linear-gradient(to top, var(--bg-primary) 0%, var(--bg-primary) 40%, transparent 100%);
    z-index: 5;
    pointer-events: none;
}

/* Hero Content - Overlay in Front */
.hero-content {
    position: relative;
    z-index: 10;
    text-align: center;
    max-width: 700px;
    padding: 40px;
    margin-top: 240px;
    background: rgba(10, 10, 11, 0.6);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-radius: var(--radius-xl);
    border: 1px solid var(--border-color);
}

[data-theme="light"] .hero-content {
    background: rgba(255, 255, 255, 0.75);
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 10px 20px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 100px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 24px;
    backdrop-filter: blur(10px);
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {

    0%,
    100% {
        opacity: 1;
        transform: scale(1);
    }

    50% {
        opacity: 0.6;
        transform: scale(1.1);
    }
}

.hero-title {
    font-size: clamp(2.25rem, 6vw, 3.5rem);
    font-weight: 700;
    line-height: 1.15;
    margin-bottom: 20px;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}

.gradient-text {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-mid), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: inline-block;
}

.hero-description {
    font-size: clamp(0.95rem, 1.5vw, 1.1rem);
    color: var(--text-secondary);
    max-width: 550px;
    margin: 0 auto 32px;
    line-height: 1.75;
}

.hero-buttons {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    font-size: 15px;
    font-weight: 600;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-base);
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
    box-shadow: 0 4px 15px rgba(139, 92, 246, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(139, 92, 246, 0.4);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

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

/* ============================================
   About Section
   ============================================ */
.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-card {
    padding: 48px;
    text-align: center;
}

.about-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    border-radius: var(--radius-lg);
    color: white;
    margin-bottom: 24px;
}

.about-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 24px;
    color: var(--text-primary);
}

.about-card p {
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.8;
}

.about-card p:last-child {
    margin-bottom: 0;
}

/* ============================================
   Skills Section
   ============================================ */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
}

.skill-card {
    padding: 32px;
}

.skill-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    color: var(--gradient-start);
    margin-bottom: 20px;
    transition: all var(--transition-base);
}

.skill-card:hover .skill-icon {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
}

.skill-card h4 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.skill-card p {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 16px;
}

/* Skill Bubbles */
.skill-bubbles {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 16px;
}

.bubble {
    display: inline-block;
    padding: 6px 14px;
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 100px;
    transition: all var(--transition-fast);
}

.skill-card:hover .bubble {
    border-color: var(--border-hover);
}

.bubble:hover {
    color: var(--text-primary);
    background: var(--bg-card-hover);
    border-color: var(--gradient-start);
}

/* ============================================
   Portfolio Section
   ============================================ */
.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 32px;
}

.portfolio-card {
    overflow: hidden;
}

.portfolio-image {
    position: relative;
    height: 200px;
    background: var(--bg-tertiary);
    overflow: hidden;
}

.portfolio-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    color: var(--text-tertiary);
    background: linear-gradient(135deg, var(--bg-secondary), var(--bg-tertiary));
    transition: all var(--transition-base);
}

.portfolio-card:hover .portfolio-placeholder {
    color: var(--gradient-start);
    transform: scale(1.05);
}

.portfolio-content {
    padding: 28px;
}

.portfolio-content h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.portfolio-content p {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 20px;
    line-height: 1.6;
}

.portfolio-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    font-weight: 600;
    color: var(--gradient-start);
    transition: all var(--transition-fast);
}

.portfolio-link:hover {
    gap: 10px;
}

/* ============================================
   Contact Section
   ============================================ */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 24px;
}

.contact-card {
    padding: 32px;
    text-align: center;
}

.contact-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    color: var(--gradient-start);
    margin-bottom: 20px;
    transition: all var(--transition-base);
}

.contact-card:hover .contact-icon {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: white;
}

.contact-card h4 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.contact-card p {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.contact-link {
    display: inline-block;
    margin-top: 8px;
    font-size: 14px;
    font-weight: 600;
    color: var(--gradient-start);
    transition: all var(--transition-fast);
}

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

/* ============================================
   Footer
   ============================================ */
.footer {
    padding: 40px 0;
    border-top: 1px solid var(--border-color);
    background: var(--bg-secondary);
}

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

.footer p {
    font-size: 14px;
    color: var(--text-tertiary);
}

.footer-links {
    display: flex;
    align-items: center;
    gap: 16px;
}

.footer-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.footer-links a:hover {
    color: var(--text-primary);
    background: var(--bg-card-hover);
    transform: translateY(-2px);
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 1024px) {
    .hero-3d-container {
        max-width: 100%;
        max-height: 700px;
    }

    .hero-content {
        max-width: 600px;
        padding: 32px;
    }
}

@media (max-width: 768px) {
    .section {
        padding: 80px 0;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .navbar.scrolled {
        width: calc(100% - 32px);
        top: 12px;
    }

    .nav-menu {
        position: fixed;
        top: 80px;
        left: 16px;
        right: 16px;
        background: rgba(24, 24, 27, 0.85);
        backdrop-filter: blur(30px);
        -webkit-backdrop-filter: blur(30px);
        border: 1px solid var(--border-color);
        border-radius: var(--radius-lg);
        flex-direction: column;
        padding: 16px;
        gap: 4px;
        transform: translateY(-20px);
        opacity: 0;
        visibility: hidden;
        transition: all var(--transition-base);
        box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    }

    [data-theme="light"] .nav-menu {
        background: rgba(255, 255, 255, 0.9);
    }

    .nav-menu.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
        background: rgba(10, 10, 11, 0.95);
        backdrop-filter: blur(50px);
        -webkit-backdrop-filter: blur(50px);
    }

    [data-theme="light"] .nav-menu.active {
        background: rgba(255, 255, 255, 0.95);
    }

    .nav-link {
        width: 100%;
        padding: 14px 16px;
        text-align: center;
    }

    .hero {
        padding: 100px 16px 60px;
        min-height: 100vh;
    }

    .hero-3d-container {
        max-width: 100%;
        max-height: 100%;
    }

    .hero-content {
        max-width: 95%;
        padding: 28px 20px;
        margin: 0 auto;
    }

    .hero-badge {
        font-size: 11px;
        padding: 8px 14px;
        margin-bottom: 20px;
    }

    .hero-title {
        font-size: clamp(1.75rem, 7vw, 2.25rem);
    }

    .hero-description {
        font-size: 0.9rem;
        margin: 0 auto 24px;
    }

    .hero-buttons {
        flex-direction: column;
        width: 100%;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }

    .about-card {
        padding: 32px 24px;
    }

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

    .contact-grid {
        grid-template-columns: 1fr;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-description {
        font-size: 1rem;
    }

    .skill-card,
    .contact-card {
        padding: 24px;
    }

    .portfolio-content {
        padding: 20px;
    }
}

/* ============================================
   Animations
   ============================================ */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

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

.hero-content>* {
    animation: fadeIn 0.6s ease forwards;
}

.hero-badge {
    animation-delay: 0.1s;
}

.hero-title {
    animation-delay: 0.2s;
}

.hero-description {
    animation-delay: 0.3s;
}

.hero-buttons {
    animation-delay: 0.4s;
}