/* ============================================
   Koushik Nagarajan — Personal Landing Page
   Dark, futuristic, AI-inspired
   ============================================ */

/* --- Reset --- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background: #0a0a1a;
    color: #e5e7eb;
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
button { font: inherit; background: none; border: none; cursor: pointer; color: inherit; }
ul { list-style: none; }

/* --- Design Tokens --- */
:root {
    --bg: #0a0a1a;
    --bg-alt: #0d0d22;
    --bg-raised: rgba(255,255,255,0.03);
    --border: rgba(255,255,255,0.08);
    --border-strong: rgba(255,255,255,0.14);
    --text: #e5e7eb;
    --text-muted: #94a3b8;
    --text-dim: #64748b;
    --cyan: #00d4ff;
    --purple: #7c3aed;
    --pink: #ec4899;
    --grad: linear-gradient(135deg, #00d4ff 0%, #7c3aed 60%, #ec4899 100%);
    --glow-cyan: 0 0 30px rgba(0,212,255,0.35);
    --glow-purple: 0 0 40px rgba(124,58,237,0.35);
    --radius: 14px;
    --radius-lg: 22px;
    --maxw: 1160px;
    --ease: cubic-bezier(0.22, 1, 0.36, 1);
}

/* --- Background ambient glow --- */
body::before {
    content: '';
    position: fixed; inset: 0;
    background:
        radial-gradient(900px 500px at 15% -10%, rgba(124,58,237,0.18), transparent 60%),
        radial-gradient(800px 500px at 100% 10%, rgba(0,212,255,0.14), transparent 60%),
        radial-gradient(600px 400px at 50% 110%, rgba(236,72,153,0.10), transparent 60%);
    z-index: -2;
    pointer-events: none;
}

/* --- Accessibility --- */
.skip-link {
    position: absolute; left: -9999px; top: 0;
    background: var(--cyan); color: #000; padding: 10px 16px;
    z-index: 1000; font-weight: 600; border-radius: 0 0 8px 0;
}
.skip-link:focus { left: 0; }

:focus-visible {
    outline: 2px solid var(--cyan);
    outline-offset: 3px;
    border-radius: 6px;
}

/* --- Layout helpers --- */
.container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 clamp(20px, 5vw, 40px);
}

/* --- Navigation --- */
.nav {
    position: fixed; top: 0; left: 0; right: 0;
    z-index: 100;
    padding: 18px 0;
    transition: background 0.3s var(--ease), backdrop-filter 0.3s var(--ease), border-color 0.3s var(--ease), padding 0.3s var(--ease);
    border-bottom: 1px solid transparent;
}
.nav.is-scrolled {
    background: rgba(10,10,26,0.72);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom-color: var(--border);
    padding: 12px 0;
}
.nav__container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 clamp(20px, 5vw, 40px);
    display: flex; align-items: center; justify-content: space-between;
    gap: 24px;
}
.nav__brand { display: flex; align-items: center; gap: 10px; font-weight: 600; }
.nav__brand-mark {
    display: inline-flex; align-items: center; justify-content: center;
    width: 36px; height: 36px;
    font-family: 'Space Grotesk', sans-serif;
    font-size: 14px; font-weight: 700;
    background: var(--grad);
    color: #fff;
    border-radius: 10px;
    box-shadow: var(--glow-cyan);
    letter-spacing: 0.5px;
}
.nav__brand-text { font-family: 'Space Grotesk', sans-serif; letter-spacing: 0.2px; }
.nav__menu { display: flex; align-items: center; gap: 6px; }
.nav__link {
    padding: 9px 14px;
    font-size: 14.5px;
    color: var(--text-muted);
    border-radius: 8px;
    transition: color 0.2s, background 0.2s;
    position: relative;
}
.nav__link:hover, .nav__link.is-active { color: var(--text); }
.nav__link.is-active::after {
    content: ''; position: absolute; bottom: 2px; left: 14px; right: 14px;
    height: 2px; background: var(--grad); border-radius: 2px;
}
.nav__link--cta {
    background: linear-gradient(135deg, rgba(0,212,255,0.12), rgba(124,58,237,0.12));
    border: 1px solid var(--border-strong);
    color: var(--text);
}
.nav__link--cta:hover {
    border-color: var(--cyan);
    box-shadow: var(--glow-cyan);
}
.nav__toggle { display: none; flex-direction: column; gap: 5px; padding: 8px; }
.nav__toggle span {
    display: block; width: 22px; height: 2px;
    background: var(--text); border-radius: 2px;
    transition: transform 0.25s, opacity 0.25s;
}
.nav__toggle.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav__toggle.is-open span:nth-child(2) { opacity: 0; }
.nav__toggle.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* --- Hero --- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex; align-items: center; justify-content: center;
    padding: 120px 0 80px;
    overflow: hidden;
}
.hero__canvas {
    position: absolute; inset: 0;
    width: 100%; height: 100%;
    z-index: 0;
    opacity: 0.55;
}
.hero__grid {
    position: absolute; inset: 0;
    background-image:
        linear-gradient(rgba(255,255,255,0.04) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.04) 1px, transparent 1px);
    background-size: 56px 56px;
    mask-image: radial-gradient(ellipse at center, black 40%, transparent 75%);
    -webkit-mask-image: radial-gradient(ellipse at center, black 40%, transparent 75%);
    z-index: 0;
    pointer-events: none;
}
.hero__content {
    position: relative; z-index: 1;
    text-align: center;
    padding: 0 clamp(20px, 5vw, 40px);
    max-width: 860px;
    margin: 0 auto;
}
.hero__avatar-wrap {
    position: relative;
    width: 140px; height: 140px;
    margin: 0 auto 28px;
}
.hero__avatar {
    width: 140px; height: 140px;
    border-radius: 50%;
    border: 2px solid var(--border-strong);
    background: var(--bg-alt);
    position: relative; z-index: 1;
}
.hero__avatar-ring {
    position: absolute; inset: -6px;
    border-radius: 50%;
    background: conic-gradient(from 0deg, #00d4ff, #7c3aed, #ec4899, #00d4ff);
    filter: blur(0.5px);
    animation: spin 8s linear infinite;
    z-index: 0;
}
.hero__avatar-ring::after {
    content: ''; position: absolute; inset: 4px;
    border-radius: 50%;
    background: var(--bg);
}
@keyframes spin { to { transform: rotate(360deg); } }

.hero__eyebrow {
    display: inline-flex; align-items: center; gap: 8px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
    color: var(--text-muted);
    padding: 6px 14px;
    border: 1px solid var(--border);
    border-radius: 999px;
    background: rgba(255,255,255,0.02);
    margin-bottom: 24px;
    letter-spacing: 0.3px;
}
.hero__dot {
    width: 8px; height: 8px; border-radius: 50%;
    background: #22c55e;
    box-shadow: 0 0 10px #22c55e;
    animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse { 0%, 100% { opacity: 1; transform: scale(1); } 50% { opacity: 0.55; transform: scale(0.8); } }

.hero__title {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 600;
    font-size: clamp(2.2rem, 5.5vw, 4rem);
    line-height: 1.1;
    letter-spacing: -0.02em;
    margin-bottom: 18px;
}
.hero__name {
    background: var(--grad);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}
.hero__role {
    font-family: 'JetBrains Mono', monospace;
    font-size: clamp(1rem, 2.4vw, 1.35rem);
    color: var(--text-muted);
    margin-bottom: 22px;
    min-height: 1.8em;
}
.hero__role-prefix { color: var(--text-dim); }
.hero__role-typed {
    color: var(--cyan);
    text-shadow: 0 0 16px rgba(0,212,255,0.4);
    padding-left: 6px;
}
.hero__cursor {
    display: inline-block;
    color: var(--cyan);
    animation: blink 1s steps(1) infinite;
    margin-left: 2px;
}
@keyframes blink { 50% { opacity: 0; } }

.hero__tagline {
    font-size: clamp(1rem, 1.6vw, 1.15rem);
    color: var(--text-muted);
    max-width: 640px;
    margin: 0 auto 36px;
}
.hero__cta {
    display: flex; flex-wrap: wrap; gap: 14px; justify-content: center;
    margin-bottom: 34px;
}
.hero__socials { display: flex; gap: 12px; justify-content: center; }

.social {
    display: inline-flex; align-items: center; justify-content: center;
    width: 44px; height: 44px;
    border: 1px solid var(--border-strong);
    border-radius: 12px;
    color: var(--text-muted);
    transition: color 0.2s, border-color 0.2s, transform 0.2s, box-shadow 0.2s, background 0.2s;
}
.social:hover {
    color: var(--cyan);
    border-color: var(--cyan);
    background: rgba(0,212,255,0.06);
    transform: translateY(-2px);
    box-shadow: var(--glow-cyan);
}

.hero__scroll {
    position: absolute;
    bottom: 28px; left: 50%;
    transform: translateX(-50%);
    display: flex; flex-direction: column; align-items: center; gap: 8px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    color: var(--text-dim);
    letter-spacing: 0.15em;
    text-transform: uppercase;
    z-index: 2;
}
.hero__scroll-line {
    width: 1px; height: 40px;
    background: linear-gradient(to bottom, transparent, var(--cyan));
    animation: scrollLine 2.2s ease-in-out infinite;
}
@keyframes scrollLine {
    0% { transform: scaleY(0); transform-origin: top; }
    50% { transform: scaleY(1); transform-origin: top; }
    50.01% { transform-origin: bottom; }
    100% { transform: scaleY(0); transform-origin: bottom; }
}

/* --- Buttons --- */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 13px 26px;
    border-radius: 12px;
    font-weight: 500;
    font-size: 15px;
    letter-spacing: 0.2px;
    transition: transform 0.2s, box-shadow 0.25s, border-color 0.2s, background 0.2s, color 0.2s;
    border: 1px solid transparent;
    position: relative;
    overflow: hidden;
}
.btn--primary {
    background: var(--grad);
    color: #fff;
    box-shadow: 0 10px 30px -10px rgba(0,212,255,0.6);
}
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 14px 36px -8px rgba(0,212,255,0.7); }
.btn--ghost {
    border-color: var(--border-strong);
    color: var(--text);
    background: rgba(255,255,255,0.02);
}
.btn--ghost:hover {
    border-color: var(--cyan);
    color: var(--cyan);
    background: rgba(0,212,255,0.06);
    transform: translateY(-2px);
}

/* --- Sections --- */
.section {
    padding: clamp(80px, 12vw, 140px) 0;
    position: relative;
}
.section--alt { background: linear-gradient(180deg, transparent, rgba(255,255,255,0.015), transparent); }
.section--contact { padding-bottom: clamp(60px, 10vw, 100px); }
.section__eyebrow {
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
    color: var(--cyan);
    text-transform: uppercase;
    letter-spacing: 0.2em;
    margin-bottom: 16px;
    display: inline-block;
}
.section__eyebrow::before { content: ''; }
.section__title {
    font-family: 'Space Grotesk', sans-serif;
    font-weight: 600;
    font-size: clamp(1.9rem, 4.2vw, 3rem);
    line-height: 1.15;
    letter-spacing: -0.02em;
    margin-bottom: 56px;
    max-width: 760px;
}
.grad {
    background: var(--grad);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
}

/* --- About --- */
.about__grid {
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: clamp(40px, 5vw, 72px);
    align-items: start;
}
.about__text p { color: var(--text-muted); font-size: 1.05rem; margin-bottom: 18px; }
.about__text strong { color: var(--text); font-weight: 600; }
.stats { display: grid; gap: 16px; }
.stat {
    padding: 22px 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--bg-raised);
    transition: border-color 0.25s, transform 0.25s, box-shadow 0.25s;
}
.stat:hover { border-color: var(--border-strong); transform: translateY(-2px); box-shadow: var(--glow-cyan); }
.stat__value {
    display: block;
    font-family: 'Space Grotesk', sans-serif;
    font-size: clamp(2rem, 4vw, 2.8rem);
    font-weight: 700;
    line-height: 1;
    background: var(--grad);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
    margin-bottom: 6px;
}
.stat__label { color: var(--text-muted); font-size: 14px; }

/* --- Cards --- */
.cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
}
.card {
    padding: 28px;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    background: linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.01));
    position: relative;
    overflow: hidden;
    transition: border-color 0.3s, transform 0.3s, box-shadow 0.3s;
}
.card::before {
    content: '';
    position: absolute; inset: 0;
    border-radius: inherit;
    padding: 1px;
    background: var(--grad);
    -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
    mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    opacity: 0;
    transition: opacity 0.3s;
    pointer-events: none;
}
.card:hover { transform: translateY(-4px); box-shadow: 0 20px 50px -20px rgba(0,212,255,0.25); }
.card:hover::before { opacity: 1; }
.card__icon {
    width: 52px; height: 52px;
    display: inline-flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, rgba(0,212,255,0.12), rgba(124,58,237,0.12));
    border: 1px solid var(--border-strong);
    border-radius: 12px;
    color: var(--cyan);
    margin-bottom: 20px;
}
.card__title {
    font-family: 'Space Grotesk', sans-serif;
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text);
}
.card__desc { color: var(--text-muted); font-size: 0.96rem; }

/* --- Leadership --- */
.leadership { max-width: 780px; }
.leadership p { color: var(--text-muted); font-size: 1.05rem; margin-bottom: 28px; }
.leadership strong { color: var(--text); font-weight: 600; }
.pills { display: flex; flex-wrap: wrap; gap: 10px; }
.pill {
    padding: 9px 18px;
    border: 1px solid var(--border-strong);
    border-radius: 999px;
    background: rgba(255,255,255,0.02);
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
    color: var(--text-muted);
    transition: color 0.2s, border-color 0.2s, background 0.2s;
}
.pill:hover { color: var(--cyan); border-color: var(--cyan); background: rgba(0,212,255,0.06); }

/* --- Contact --- */
.contact__lead { color: var(--text-muted); font-size: 1.1rem; max-width: 620px; margin-bottom: 40px; }
.contact__cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 18px;
    max-width: 780px;
}
.contact-card {
    display: flex; align-items: center; gap: 18px;
    padding: 22px 26px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--bg-raised);
    transition: border-color 0.25s, transform 0.25s, box-shadow 0.25s, background 0.25s;
}
.contact-card:hover {
    border-color: var(--cyan);
    transform: translateY(-3px);
    box-shadow: var(--glow-cyan);
    background: rgba(0,212,255,0.04);
}
.contact-card__icon {
    display: inline-flex; align-items: center; justify-content: center;
    width: 52px; height: 52px; flex-shrink: 0;
    border-radius: 12px;
    background: linear-gradient(135deg, rgba(0,212,255,0.12), rgba(124,58,237,0.12));
    color: var(--cyan);
}
.contact-card__title { font-family: 'Space Grotesk', sans-serif; font-size: 1.1rem; font-weight: 600; margin-bottom: 2px; }
.contact-card__desc { font-size: 0.9rem; color: var(--text-muted); }
.contact-card__arrow {
    margin-left: auto;
    font-size: 20px;
    color: var(--text-dim);
    transition: transform 0.25s, color 0.25s;
}
.contact-card:hover .contact-card__arrow { color: var(--cyan); transform: translateX(4px); }

/* --- Footer --- */
.footer {
    padding: 34px 0;
    border-top: 1px solid var(--border);
    color: var(--text-dim);
    font-size: 14px;
}
.footer__inner {
    display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px;
}
.footer__meta { color: var(--text-muted); }

/* --- Reveal on scroll --- */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.7s var(--ease), transform 0.7s var(--ease);
}
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* --- Responsive --- */
@media (max-width: 820px) {
    .nav__menu {
        position: fixed; top: 64px; right: 16px; left: 16px;
        flex-direction: column; align-items: stretch; gap: 6px;
        padding: 14px;
        background: rgba(10,10,26,0.96);
        backdrop-filter: blur(18px);
        -webkit-backdrop-filter: blur(18px);
        border: 1px solid var(--border);
        border-radius: 14px;
        transform: translateY(-10px);
        opacity: 0;
        pointer-events: none;
        transition: opacity 0.25s, transform 0.25s;
    }
    .nav__menu.is-open { opacity: 1; transform: translateY(0); pointer-events: auto; }
    .nav__link { padding: 12px 14px; }
    .nav__toggle { display: flex; }
    .about__grid { grid-template-columns: 1fr; }
    .hero { padding: 110px 0 70px; }
}

@media (max-width: 520px) {
    .hero__cta { flex-direction: column; width: 100%; }
    .hero__cta .btn { width: 100%; }
    .hero__scroll { display: none; }
}

/* --- Reduced Motion --- */
@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    .reveal { opacity: 1; transform: none; }
    .hero__avatar-ring { animation: none; background: var(--grad); }
    .hero__canvas { display: none; }
    .hero__cursor { animation: none; }
}