/* ================================
   CSS Variables & Reset
   ================================ */
:root {
    /* Colors */
    --primary: #64ffda;
    --primary-dim: rgba(100, 255, 218, 0.15);
    --secondary: #0f172a;
    --accent: #6366f1;
    --accent-hover: #818cf8;
    --bg-primary: #0a0f1a;
    --bg-secondary: #111827;
    --bg-card: #1a2332;
    --text-primary: #e2e8f0;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --border: #1e293b;
    --border-light: #334155;

    /* Typography */
    --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    --font-sans: 'Noto Sans SC', 'Source Han Sans SC', -apple-system, sans-serif;

    /* Spacing */
    --section-padding: 100px;
    --container-max: 1100px;
    --nav-height: 70px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 300ms ease;
    --transition-slow: 500ms ease;
}

*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--nav-height);
}

body {
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

::selection {
    background-color: var(--primary);
    color: var(--bg-primary);
}

::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--border-light);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}

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

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

button {
    font-family: inherit;
    cursor: pointer;
    border: none;
    background: none;
}

ul, ol {
    list-style: none;
}

/* ================================
   Utilities
   ================================ */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: var(--section-padding) 0;
}

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ================================
   Navbar
   ================================ */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--nav-height);
    background: rgba(10, 15, 26, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    z-index: 1000;
}

.nav-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    transition: var(--transition-base);
}

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

.logo-text {
    color: var(--text-primary);
}

.logo:hover .logo-bracket {
    text-shadow: 0 0 20px var(--primary);
}

.nav-links {
    display: flex;
    gap: 32px;
}

.nav-link {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--text-secondary);
    position: relative;
    padding: 8px 0;
    transition: color var(--transition-fast);
}

.nav-link::before {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width var(--transition-base);
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary);
}

.nav-link:hover::before,
.nav-link.active::before {
    width: 100%;
}

.menu-toggle {
    display: none;
    width: 32px;
    height: 32px;
    position: relative;
    z-index: 1001;
}

.hamburger {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    transition: background var(--transition-fast);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    left: 0;
    transition: transform var(--transition-base);
}

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

.hamburger::after {
    top: 7px;
}

.menu-toggle.active .hamburger {
    background: transparent;
}

.menu-toggle.active .hamburger::before {
    transform: translateY(7px) rotate(45deg);
}

.menu-toggle.active .hamburger::after {
    transform: translateY(-7px) rotate(-45deg);
}

/* ================================
   Hero Section
   ================================ */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: calc(var(--nav-height) + 40px) 24px 80px;
    overflow: hidden;
}

.hero-bg-grid {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(100, 255, 218, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(100, 255, 218, 0.03) 1px, transparent 1px);
    background-size: 60px 60px;
    mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 40%, transparent 100%);
}

.hero-content {
    text-align: center;
    max-width: 700px;
    position: relative;
    z-index: 1;
}

.hero-greeting {
    font-family: var(--font-mono);
    font-size: 1rem;
    color: var(--primary);
    margin-bottom: 16px;
    opacity: 0;
    animation: fadeInUp 0.5s ease forwards;
}

.hero-title {
    font-family: var(--font-mono);
    font-size: clamp(3rem, 8vw, 5rem);
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -2px;
    margin-bottom: 16px;
    opacity: 0;
    animation: fadeInUp 0.5s ease 0.1s forwards;
}

.hero-tagline-wrapper {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    margin-bottom: 24px;
    min-height: 42px;
    opacity: 0;
    animation: fadeInUp 0.5s ease 0.2s forwards;
}

.hero-prompt {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    color: var(--primary);
}

.hero-tagline {
    font-family: var(--font-mono);
    font-size: clamp(1.25rem, 4vw, 1.75rem);
    color: var(--text-secondary);
    font-weight: 400;
}

.hero-cursor {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    color: var(--primary);
    animation: blink 1s step-end infinite;
}

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

.hero-desc {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 550px;
    margin: 0 auto 40px;
    opacity: 0;
    animation: fadeInUp 0.5s ease 0.3s forwards;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    opacity: 0;
    animation: fadeInUp 0.5s ease 0.4s forwards;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    font-family: var(--font-mono);
    font-size: 0.9rem;
    font-weight: 500;
    border-radius: 6px;
    transition: all var(--transition-base);
}

.btn-primary {
    background: var(--primary);
    color: var(--bg-primary);
}

.btn-primary:hover {
    background: #8fffda;
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(100, 255, 218, 0.3);
}

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

.btn-secondary:hover {
    background: var(--primary-dim);
    transform: translateY(-2px);
}

.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-family: var(--font-mono);
    font-size: 0.75rem;
    letter-spacing: 2px;
    text-transform: uppercase;
    animation: bounce 2s ease-in-out infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(8px); }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ================================
   Section Common
   ================================ */
.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--primary);
    opacity: 0.7;
}

.section-title {
    font-family: var(--font-mono);
    font-size: clamp(2rem, 5vw, 2.5rem);
    color: var(--text-primary);
    margin: 8px 0;
    letter-spacing: -1px;
}

/* ================================
   About Section
   ================================ */
.about {
    background: var(--bg-secondary);
}

.about-content {
    display: grid;
    grid-template-columns: 280px 1fr;
    gap: 60px;
    align-items: center;
}

.about-avatar {
    position: relative;
}

.avatar-shape {
    width: 220px;
    height: 220px;
    position: relative;
    margin: 0 auto;
}

.avatar-shape::before {
    content: '';
    position: absolute;
    inset: 0;
    border: 2px solid var(--primary);
    border-radius: 12px;
    transform: rotate(3deg);
    opacity: 0.5;
}

.avatar-inner {
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-secondary) 100%);
    border: 2px solid var(--primary);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.avatar-inner::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        repeating-linear-gradient(
            0deg,
            transparent,
            transparent 20px,
            rgba(100, 255, 218, 0.03) 20px,
            rgba(100, 255, 218, 0.03) 21px
        );
}

.avatar-code {
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--primary);
    line-height: 1.8;
    text-align: left;
    padding: 20px;
}

.avatar-decoration {
    position: absolute;
    width: 60px;
    height: 60px;
    border: 2px solid var(--primary);
    border-radius: 50%;
    bottom: -10px;
    right: 20px;
    opacity: 0.3;
}

.about-text {
    max-width: 600px;
}

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

.about-text p:first-child {
    font-size: 1.25rem;
    color: var(--text-primary);
}

.about-info {
    display: flex;
    flex-wrap: wrap;
    gap: 24px;
    margin-top: 32px;
    padding-top: 24px;
    border-top: 1px solid var(--border);
}

.info-item {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.info-item svg {
    color: var(--primary);
}

/* ================================
   Skills Section
   ================================ */
.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
}

.skill-card {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 28px;
    transition: all var(--transition-base);
}

.skill-card:hover {
    border-color: var(--primary);
    box-shadow: 0 0 30px rgba(100, 255, 218, 0.1);
    transform: translateY(-4px);
}

.skill-card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 20px;
}

.skill-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary-dim);
    border-radius: 10px;
    color: var(--primary);
}

.skill-card-header h3 {
    font-family: var(--font-mono);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.skill-tag {
    padding: 6px 14px;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 20px;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

.skill-tag:hover {
    background: var(--primary-dim);
    border-color: var(--primary);
    color: var(--primary);
}

/* ================================
   Projects Section
   ================================ */
.projects {
    background: var(--bg-secondary);
}

.projects-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 28px;
}

.project-card {
    background: var(--bg-primary);
    border: 1px solid var(--border);
    border-radius: 16px;
    overflow: hidden;
    transition: all var(--transition-base);
}

.project-card:hover {
    border-color: var(--primary);
    transform: translateY(-6px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.3);
}

.project-cover {
    height: 160px;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.project-cover::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(0,0,0,0.4) 0%, transparent 60%);
}

.cover-icon {
    color: rgba(255, 255, 255, 0.3);
}

.cover-1 {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.cover-2 {
    background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}

.cover-3 {
    background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}

.cover-4 {
    background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
}

.project-content {
    padding: 24px;
}

.project-title {
    font-family: var(--font-mono);
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.project-desc {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.6;
}

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

.project-tech span {
    padding: 4px 10px;
    background: var(--bg-secondary);
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--primary);
}

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

.project-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-family: var(--font-mono);
    font-size: 0.85rem;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.project-link:hover {
    color: var(--primary);
}

/* ================================
   Contact Section
   ================================ */
.contact-content {
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.contact-text p {
    color: var(--text-secondary);
    margin-bottom: 32px;
}

.contact-email {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    padding: 16px 32px;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    font-family: var(--font-mono);
    font-size: 1.1rem;
    color: var(--text-primary);
    transition: all var(--transition-base);
}

.contact-email:hover {
    border-color: var(--primary);
    color: var(--primary);
    box-shadow: 0 0 20px rgba(100, 255, 218, 0.15);
}

.contact-email svg {
    color: var(--primary);
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 48px;
}

.social-link {
    width: 52px;
    height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 50%;
    color: var(--text-secondary);
    transition: all var(--transition-base);
}

.social-link:hover {
    color: var(--primary);
    border-color: var(--primary);
    transform: translateY(-4px) rotate(8deg);
    box-shadow: 0 8px 20px rgba(100, 255, 218, 0.2);
}

/* ================================
   Footer
   ================================ */
.footer {
    padding: 40px 0;
    border-top: 1px solid var(--border);
    text-align: center;
}

.footer-content {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-text {
    font-family: var(--font-mono);
    font-size: 1rem;
}

.footer-code {
    color: var(--primary);
}

.footer-message {
    color: var(--text-secondary);
    margin: 0 8px;
}

.footer-copyright {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ================================
   Responsive Design
   ================================ */
@media (max-width: 1024px) {
    :root {
        --section-padding: 80px;
    }
}

@media (max-width: 768px) {
    :root {
        --section-padding: 60px;
        --nav-height: 60px;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        width: 100%;
        height: 100vh;
        background: var(--bg-primary);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 40px;
        transition: right var(--transition-base);
    }

    .nav-links.active {
        right: 0;
    }

    .nav-link {
        font-size: 1.5rem;
    }

    .menu-toggle {
        display: block;
    }

    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
    }

    .about-avatar {
        order: -1;
    }

    .about-info {
        justify-content: center;
    }

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

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

    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }

    .btn {
        width: 100%;
        max-width: 280px;
        justify-content: center;
    }

    .scroll-indicator {
        display: none;
    }
}

@media (max-width: 480px) {
    .section-title {
        font-size: 1.75rem;
    }

    .hero-title {
        letter-spacing: -1px;
    }

    .contact-email {
        font-size: 0.9rem;
        padding: 14px 20px;
    }

    .social-link {
        width: 44px;
        height: 44px;
    }
}