/* ============================================
   HEARTEU02 PORTFOLIO — STYLE SYSTEM
   ============================================ */

/* === CSS Variables / Theming === */
:root {
    /* Shared */
    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);

    /* Spacing */
    --section-padding: 120px 0;
    --container-width: 1200px;
    --container-padding: 0 24px;
}

/* Dark Theme (default) */
[data-theme="dark"] {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: rgba(255, 255, 255, 0.03);
    --bg-card-hover: rgba(255, 255, 255, 0.06);
    --bg-glass: rgba(255, 255, 255, 0.04);
    --bg-nav: rgba(10, 10, 15, 0.8);
    --border-color: rgba(255, 255, 255, 0.06);
    --border-hover: rgba(255, 255, 255, 0.12);
    --text-primary: #f0f0f5;
    --text-secondary: #8888a0;
    --text-muted: #555570;
    --accent-1: #6c5ce7;
    --accent-2: #00cec9;
    --accent-3: #fd79a8;
    --gradient-main: linear-gradient(135deg, #6c5ce7, #00cec9);
    --gradient-accent: linear-gradient(135deg, #6c5ce7, #fd79a8);
    --glow-color: rgba(108, 92, 231, 0.15);
    --shadow-card: 0 4px 30px rgba(0, 0, 0, 0.3);
    --orb-1: rgba(108, 92, 231, 0.08);
    --orb-2: rgba(0, 206, 201, 0.06);
    --orb-3: rgba(253, 121, 168, 0.05);
}

/* Light Theme */
[data-theme="light"] {
    --bg-primary: #fafbff;
    --bg-secondary: #f0f2f8;
    --bg-card: rgba(255, 255, 255, 0.7);
    --bg-card-hover: rgba(255, 255, 255, 0.9);
    --bg-glass: rgba(255, 255, 255, 0.6);
    --bg-nav: rgba(250, 251, 255, 0.85);
    --border-color: rgba(0, 0, 0, 0.06);
    --border-hover: rgba(0, 0, 0, 0.12);
    --text-primary: #1a1a2e;
    --text-secondary: #5a5a7a;
    --text-muted: #9090a8;
    --accent-1: #5b4cdb;
    --accent-2: #00b4b0;
    --accent-3: #e8608a;
    --gradient-main: linear-gradient(135deg, #5b4cdb, #00b4b0);
    --gradient-accent: linear-gradient(135deg, #5b4cdb, #e8608a);
    --glow-color: rgba(91, 76, 219, 0.1);
    --shadow-card: 0 4px 30px rgba(0, 0, 0, 0.06);
    --orb-1: rgba(91, 76, 219, 0.08);
    --orb-2: rgba(0, 180, 176, 0.06);
    --orb-3: rgba(232, 96, 138, 0.06);
}

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

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

body {
    font-family: var(--font-main);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    overflow-x: hidden;
    transition: background var(--transition), color var(--transition);
}

::selection {
    background: var(--accent-1);
    color: #fff;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

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

/* === Ambient Background === */
.ambient-bg {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    z-index: 0;
    pointer-events: none;
    overflow: hidden;
}

.orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.6;
}

.orb-1 {
    width: 600px; height: 600px;
    background: var(--orb-1);
    top: -200px; right: -100px;
    animation: orbFloat1 20s ease-in-out infinite;
}

.orb-2 {
    width: 500px; height: 500px;
    background: var(--orb-2);
    bottom: -150px; left: -100px;
    animation: orbFloat2 25s ease-in-out infinite;
}

.orb-3 {
    width: 400px; height: 400px;
    background: var(--orb-3);
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    animation: orbFloat3 30s ease-in-out infinite;
}

@keyframes orbFloat1 {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(-80px, 80px); }
}

@keyframes orbFloat2 {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(60px, -60px); }
}

@keyframes orbFloat3 {
    0%, 100% { transform: translate(-50%, -50%) scale(1); }
    50% { transform: translate(-50%, -50%) scale(1.2); }
}

/* === Navigation === */
.navbar {
    position: fixed;
    top: 0; left: 0;
    width: 100%;
    z-index: 1000;
    padding: 16px 0;
    transition: all var(--transition);
}

.navbar.scrolled {
    background: var(--bg-nav);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-color);
    padding: 12px 0;
}

.nav-container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: var(--container-padding);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    font-family: var(--font-mono);
    font-size: 1.1rem;
    font-weight: 600;
    letter-spacing: -0.5px;
    transition: opacity var(--transition);
}

.nav-logo:hover { opacity: 0.7; }

.logo-bracket {
    color: var(--accent-1);
}

.nav-links {
    display: flex;
    gap: 36px;
}

.nav-link {
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px; left: 0;
    width: 0; height: 2px;
    background: var(--gradient-main);
    transition: width var(--transition);
    border-radius: 2px;
}

.nav-link:hover { color: var(--text-primary); }
.nav-link:hover::after { width: 100%; }

.nav-link.active { color: var(--text-primary); }
.nav-link.active::after { width: 100%; }

.nav-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

/* Theme Toggle */
.theme-toggle {
    width: 40px; height: 40px;
    border-radius: 50%;
    border: 1px solid var(--border-color);
    background: var(--bg-glass);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition);
    position: relative;
    color: var(--text-secondary);
}

.theme-toggle:hover {
    border-color: var(--accent-1);
    color: var(--accent-1);
    transform: rotate(180deg);
}

.theme-icon {
    width: 18px; height: 18px;
    position: absolute;
    transition: opacity var(--transition);
}

[data-theme="dark"] .sun-icon { opacity: 1; }
[data-theme="dark"] .moon-icon { opacity: 0; }
[data-theme="light"] .sun-icon { opacity: 0; }
[data-theme="light"] .moon-icon { opacity: 1; }

/* Mobile Menu Button */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.mobile-menu-btn span {
    width: 22px; height: 2px;
    background: var(--text-secondary);
    border-radius: 2px;
    transition: all var(--transition);
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translateY(5px) translateX(4px);
}
.mobile-menu-btn.active span:nth-child(2) { opacity: 0; }
.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translateY(-5px) translateX(4px);
}

/* === Hero Section === */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    z-index: 1;
    padding: 120px 24px 80px;
}

.hero-content {
    max-width: 800px;
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 20px;
    border-radius: 100px;
    font-size: 0.82rem;
    font-weight: 500;
    color: var(--accent-2);
    background: rgba(0, 206, 201, 0.08);
    border: 1px solid rgba(0, 206, 201, 0.15);
    margin-bottom: 32px;
}

.status-dot {
    width: 8px; height: 8px;
    background: var(--accent-2);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(0.8); }
}

.hero-title {
    margin-bottom: 24px;
}

.hero-greeting {
    display: block;
    font-size: 1.1rem;
    font-weight: 400;
    color: var(--text-secondary);
    letter-spacing: 2px;
    text-transform: uppercase;
    margin-bottom: 12px;
}

.hero-name {
    display: block;
    font-size: clamp(2.8rem, 7vw, 5rem);
    font-weight: 800;
    letter-spacing: -2px;
    line-height: 1.05;
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-tagline {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 20px;
    font-weight: 400;
    min-height: 30px;
}

.typed-text {
    color: var(--accent-1);
    font-weight: 600;
}

.cursor-blink {
    color: var(--accent-1);
    animation: blink 1s step-end infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0; }
}

.hero-description {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 620px;
    margin: 0 auto 40px;
    line-height: 1.8;
}

.hero-cta {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-bottom: 60px;
    flex-wrap: wrap;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 14px 28px;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 0.92rem;
    transition: all var(--transition);
    cursor: pointer;
    border: none;
    font-family: var(--font-main);
}

.btn i { width: 18px; height: 18px; }

.btn-primary {
    background: var(--gradient-main);
    color: #fff;
    box-shadow: 0 4px 20px rgba(108, 92, 231, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(108, 92, 231, 0.4);
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-outline:hover {
    border-color: var(--accent-1);
    background: var(--bg-card);
    transform: translateY(-2px);
}

/* Hero Stats */
.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 32px;
}

.stat { text-align: center; }

.stat-number {
    display: block;
    font-size: 1.8rem;
    font-weight: 800;
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 0.78rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: 500;
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--border-color);
}

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    color: var(--text-muted);
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.scroll-line {
    width: 1px;
    height: 40px;
    background: var(--gradient-main);
    animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
    0%, 100% { opacity: 0.3; transform: scaleY(1); }
    50% { opacity: 1; transform: scaleY(0.6); }
}

/* === Section Commons === */
.section {
    padding: var(--section-padding);
    position: relative;
    z-index: 1;
}

.section-alt {
    background: var(--bg-secondary);
}

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

.section-tag {
    display: inline-block;
    font-family: var(--font-mono);
    font-size: 0.82rem;
    font-weight: 500;
    color: var(--accent-1);
    margin-bottom: 16px;
    letter-spacing: 1px;
}

.section-title {
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800;
    letter-spacing: -1px;
    line-height: 1.15;
    margin-bottom: 16px;
}

.gradient-text {
    background: var(--gradient-main);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-subtitle {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 500px;
    margin: 0 auto;
}

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

.about-text p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 24px;
    line-height: 1.85;
}

.about-highlights {
    display: grid;
    gap: 16px;
    margin-top: 40px;
}

.highlight-item {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    padding: 20px 24px;
    border-radius: var(--radius-md);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
}

.highlight-item:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateX(4px);
}

.highlight-item i {
    width: 22px; height: 22px;
    color: var(--accent-1);
    flex-shrink: 0;
    margin-top: 2px;
}

.highlight-item strong {
    display: block;
    font-weight: 600;
    margin-bottom: 2px;
}

.highlight-item span {
    font-size: 0.88rem;
    color: var(--text-secondary);
}

/* === Projects Section === */
.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: 24px;
}

.project-card {
    position: relative;
    padding: 32px;
    border-radius: var(--radius-lg);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
    overflow: hidden;
}

.project-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0;
    width: 100%; height: 100%;
    background: var(--gradient-main);
    opacity: 0;
    transition: opacity var(--transition);
    z-index: 0;
}

.project-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-4px);
    box-shadow: var(--shadow-card);
}

.project-card:hover::before {
    opacity: 0.03;
}

.project-card > * { position: relative; z-index: 1; }

.project-card-glow {
    position: absolute;
    top: -1px; left: -1px;
    right: -1px; bottom: -1px;
    border-radius: var(--radius-lg);
    background: var(--gradient-main);
    opacity: 0;
    z-index: 0;
    transition: opacity var(--transition);
}

.project-card:hover .project-card-glow {
    opacity: 0.1;
}

.project-card.featured {
    grid-column: 1 / -1;
    background: var(--bg-card);
    border: 1px solid rgba(108, 92, 231, 0.15);
}

.project-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 20px;
}

.project-icon {
    width: 48px; height: 48px;
    border-radius: var(--radius-md);
    background: var(--glow-color);
    display: flex;
    align-items: center;
    justify-content: center;
}

.project-icon i {
    width: 24px; height: 24px;
    color: var(--accent-1);
}

.project-badges {
    display: flex;
    gap: 8px;
}

.badge {
    padding: 4px 12px;
    border-radius: 100px;
    font-size: 0.72rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-live {
    background: rgba(0, 206, 201, 0.1);
    color: var(--accent-2);
    border: 1px solid rgba(0, 206, 201, 0.2);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.live-dot {
    width: 6px; height: 6px;
    background: var(--accent-2);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

.badge-production {
    background: rgba(108, 92, 231, 0.1);
    color: var(--accent-1);
    border: 1px solid rgba(108, 92, 231, 0.2);
}

.badge-ai {
    background: rgba(253, 121, 168, 0.1);
    color: var(--accent-3);
    border: 1px solid rgba(253, 121, 168, 0.2);
}

.badge-web3 {
    background: rgba(0, 206, 201, 0.1);
    color: var(--accent-2);
    border: 1px solid rgba(0, 206, 201, 0.2);
}

.project-title {
    font-size: 1.3rem;
    font-weight: 700;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.project-description {
    font-size: 0.92rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 20px;
}

.project-tech {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 20px;
}

.tech-tag {
    padding: 4px 12px;
    border-radius: 100px;
    font-size: 0.75rem;
    font-weight: 500;
    background: var(--bg-glass);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
}

.project-links {
    display: flex;
    gap: 16px;
}

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.88rem;
    font-weight: 500;
    color: var(--accent-1);
    transition: all var(--transition);
}

.project-link:hover { color: var(--accent-2); }
.project-link i { width: 16px; height: 16px; }

.private-link {
    color: var(--text-muted);
    cursor: default;
}

.private-link:hover { color: var(--text-muted); }

/* === Tech Stack === */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 24px;
}

.tech-category {
    padding: 28px;
    border-radius: var(--radius-lg);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    transition: all var(--transition);
}

.tech-category:hover {
    border-color: var(--border-hover);
    transform: translateY(-2px);
}

.tech-category-title {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.92rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.tech-category-title i {
    width: 20px; height: 20px;
    color: var(--accent-1);
}

.tech-items {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tech-item {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-weight: 500;
    background: var(--bg-glass);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    transition: all var(--transition);
}

.tech-item:hover {
    border-color: var(--accent-1);
    color: var(--accent-1);
    background: var(--glow-color);
}

/* === Contact Section === */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
    max-width: 900px;
    margin: 0 auto;
}

.contact-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    padding: 40px 28px;
    border-radius: var(--radius-lg);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    text-align: center;
    transition: all var(--transition);
}

.contact-card:hover {
    border-color: var(--accent-1);
    transform: translateY(-4px);
    box-shadow: var(--shadow-card);
}

.contact-card i {
    width: 28px; height: 28px;
    color: var(--accent-1);
}

.contact-label {
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1.5px;
}

.contact-value {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-primary);
}

/* === Footer === */
.footer {
    position: relative;
    z-index: 1;
    padding: 40px 0;
    border-top: 1px solid var(--border-color);
}

.footer-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 16px;
}

.footer-logo {
    font-family: var(--font-mono);
    font-size: 0.92rem;
    font-weight: 600;
}

.footer-text {
    font-size: 0.82rem;
    color: var(--text-muted);
}

/* === Scroll Animations === */
.animate-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

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

.animate-in:nth-child(2) { transition-delay: 0.1s; }
.animate-in:nth-child(3) { transition-delay: 0.2s; }
.animate-in:nth-child(4) { transition-delay: 0.3s; }
.animate-in:nth-child(5) { transition-delay: 0.4s; }
.animate-in:nth-child(6) { transition-delay: 0.5s; }
.animate-in:nth-child(7) { transition-delay: 0.6s; }

/* Section-level scroll animations */
.section .section-header,
.section .about-grid,
.section .projects-grid,
.section .tech-grid,
.section .contact-grid {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.section .section-header.visible,
.section .about-grid.visible,
.section .projects-grid.visible,
.section .tech-grid.visible,
.section .contact-grid.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Project card stagger */
.project-card {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out, border-color var(--transition), box-shadow var(--transition);
}

.project-card.visible {
    opacity: 1;
    transform: translateY(0);
}

/* === Responsive === */
@media (max-width: 768px) {
    :root {
        --section-padding: 80px 0;
    }

    .nav-links {
        display: none;
        position: fixed;
        top: 0; left: 0;
        width: 100%; height: 100vh;
        background: var(--bg-primary);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 32px;
        z-index: 999;
    }

    .nav-links.active {
        display: flex;
    }

    .nav-links .nav-link {
        font-size: 1.4rem;
        font-weight: 600;
    }

    .mobile-menu-btn {
        display: flex;
        z-index: 1001;
    }

    .hero {
        padding: 100px 20px 60px;
    }

    .hero-name {
        font-size: 2.6rem;
    }

    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }

    .stat-divider {
        width: 40px; height: 1px;
    }

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

    .project-card.featured {
        grid-column: auto;
    }

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

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

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

    .scroll-indicator { display: none; }
}

@media (max-width: 480px) {
    .hero-name { font-size: 2.2rem; }
    .hero-description { font-size: 0.95rem; }
    .hero-cta { flex-direction: column; align-items: center; }
    .btn { width: 100%; justify-content: center; }
    .section-title { font-size: 1.8rem; }
}