/* =====================
   CSS Custom Properties
   ===================== */
:root {
    --bg-primary: #080d1a;
    --bg-secondary: #0f172a;
    --bg-card: #1e293b;
    --bg-card-hover: #263346;
    --accent-primary: #6366f1;
    --accent-secondary: #22d3ee;
    --accent-gradient: linear-gradient(135deg, #6366f1, #22d3ee);
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #475569;
    --border: rgba(255, 255, 255, 0.08);
    --nav-bg: rgba(8, 13, 26, 0.85);
    --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);
    --radius: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

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

/* =====================
   Navigation
   ===================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 16px 40px;
    background: var(--nav-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    z-index: 1000;
    transition: var(--transition);
}

.navbar.scrolled {
    padding: 12px 40px;
    background: rgba(8, 13, 26, 0.97);
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: 800;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -0.5px;
}

.menu {
    list-style: none;
    display: flex;
    gap: 36px;
    align-items: center;
}

.nav-link {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition);
    position: relative;
    padding: 4px 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent-gradient);
    transition: width 0.3s ease;
    border-radius: 2px;
}

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

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

/* Hamburger */
.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 4px;
    background: none;
    border: none;
}

.menu-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 2px;
    transition: var(--transition);
}

/* =====================
   Container
   ===================== */
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* =====================
   Buttons
   ===================== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 0.95rem;
    font-weight: 600;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--accent-gradient);
    color: #fff;
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.5);
}

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

.btn-outline:hover {
    border-color: var(--accent-primary);
    color: var(--accent-primary);
    transform: translateY(-2px);
}

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

.hero-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 60% 50% at 50% 20%, rgba(99, 102, 241, 0.15) 0%, transparent 70%),
        radial-gradient(ellipse 40% 40% at 80% 80%, rgba(34, 211, 238, 0.08) 0%, transparent 60%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 760px;
}

.hero-greeting {
    display: inline-block;
    font-size: 1rem;
    font-weight: 500;
    color: var(--accent-secondary);
    letter-spacing: 0.12em;
    text-transform: uppercase;
    margin-bottom: 16px;
}

.hero-name {
    font-size: clamp(2.4rem, 6vw, 4.5rem);
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -1px;
    margin-bottom: 20px;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-titles {
    font-size: clamp(1.1rem, 2.5vw, 1.5rem);
    color: var(--text-secondary);
    font-weight: 400;
    margin-bottom: 24px;
    min-height: 2em;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
}

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

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

.hero-description {
    font-size: 1.05rem;
    color: var(--text-secondary);
    max-width: 520px;
    margin: 0 auto 40px;
    line-height: 1.7;
}

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

/* Scroll Indicator */
.scroll-indicator {
    position: absolute;
    bottom: 36px;
    left: 50%;
    transform: translateX(-50%);
    width: 24px;
    height: 38px;
    border: 2px solid var(--text-muted);
    border-radius: 12px;
    display: flex;
    justify-content: center;
    padding-top: 6px;
}

.scroll-dot {
    width: 4px;
    height: 8px;
    background: var(--accent-primary);
    border-radius: 2px;
    animation: scroll-bounce 2s infinite;
}

@keyframes scroll-bounce {
    0%, 100% { transform: translateY(0); opacity: 1; }
    50% { transform: translateY(10px); opacity: 0.3; }
}

/* =====================
   Section Common
   ===================== */
.section {
    padding: 100px 0;
}

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

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.1);
    padding: 5px 14px;
    border-radius: 20px;
    margin-bottom: 16px;
    border: 1px solid rgba(99, 102, 241, 0.2);
}

.section-title {
    font-size: clamp(1.8rem, 4vw, 2.8rem);
    font-weight: 700;
    letter-spacing: -0.5px;
    color: var(--text-primary);
}

/* =====================
   About Section
   ===================== */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}

.about-text p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

.about-text strong {
    color: var(--text-primary);
    font-weight: 600;
}

.skills-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.skill-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 20px;
    transition: var(--transition);
}

.skill-card:hover {
    border-color: rgba(99, 102, 241, 0.35);
    transform: translateY(-3px);
    box-shadow: var(--shadow-card);
}

.skill-icon {
    font-size: 1.5rem;
    background: var(--accent-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 10px;
    display: block;
}

.skill-card h3 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.skill-card p {
    font-size: 0.82rem;
    color: var(--text-muted);
    line-height: 1.4;
}

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

.project-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.project-card:hover {
    border-color: rgba(99, 102, 241, 0.4);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.4);
}

.project-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: rgba(99, 102, 241, 0.12);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    color: var(--accent-primary);
}

.project-card h3 {
    font-size: 1.05rem;
    font-weight: 600;
    color: var(--text-primary);
}

.project-card p {
    font-size: 0.88rem;
    color: var(--text-secondary);
    line-height: 1.6;
    flex: 1;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.tag {
    font-size: 0.72rem;
    font-weight: 500;
    padding: 3px 10px;
    border-radius: 20px;
    background: rgba(34, 211, 238, 0.08);
    color: var(--accent-secondary);
    border: 1px solid rgba(34, 211, 238, 0.15);
}

.project-link {
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--accent-primary);
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: var(--transition);
    margin-top: auto;
}

.project-link:hover {
    color: var(--accent-secondary);
    gap: 10px;
}

/* =====================
   Contact Section
   ===================== */
.contact-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.05rem;
    margin-bottom: 48px;
    margin-top: -20px;
}

.contact-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    max-width: 900px;
    margin: 0 auto;
}

.contact-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 28px;
    display: flex;
    align-items: center;
    gap: 20px;
    transition: var(--transition);
}

.contact-card:hover {
    border-color: rgba(99, 102, 241, 0.4);
    transform: translateY(-3px);
    box-shadow: var(--shadow-card);
}

.contact-icon {
    width: 52px;
    height: 52px;
    border-radius: 14px;
    background: rgba(99, 102, 241, 0.12);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    color: var(--accent-primary);
    flex-shrink: 0;
}

.contact-card h3 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 3px;
}

.contact-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* =====================
   Footer
   ===================== */
footer {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 32px 0;
}

.footer-content {
    text-align: center;
}

.footer-name {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 6px;
}

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

/* =====================
   Fade-in Animations
   ===================== */
.fade-in {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* =====================
   Responsive
   ===================== */
@media (max-width: 768px) {
    .navbar {
        padding: 14px 20px;
    }

    .navbar.scrolled {
        padding: 10px 20px;
    }

    .menu-toggle {
        display: flex;
    }

    .menu {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 260px;
        background: var(--bg-secondary);
        border-left: 1px solid var(--border);
        flex-direction: column;
        justify-content: center;
        gap: 36px;
        padding: 40px;
        transition: right 0.3s ease;
        z-index: 999;
    }

    .menu.open {
        right: 0;
    }

    .nav-link {
        font-size: 1.2rem;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-section {
        padding: 100px 20px 80px;
    }

    .section {
        padding: 70px 0;
    }
}

@media (max-width: 480px) {
    .hero-cta {
        flex-direction: column;
        align-items: center;
    }

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

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