/* =========================
   RESET
========================= */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
}

/* =========================
   SMOOTH SCROLL
========================= */
html {
    scroll-behavior: smooth;
}

/* =========================
   BODY + 3D BACKDROP
========================= */
body {
    background: radial-gradient(1200px 600px at 50% -10%, #153a5f 0%, rgba(21, 58, 95, 0) 60%),
        #060916;
    color: rgba(235, 245, 255, 0.92);
    line-height: 1.7;
    overflow-x: hidden;
}

#bg3d {
    position: fixed;
    inset: 0;
    width: 100vw;
    height: 100vh;
    z-index: 0;
    pointer-events: none;
    opacity: 1;
}

header,
.hero,
.content-section,
footer {
    position: relative;
    z-index: 1;
}

/*******************************
  Tech UI tokens
********************************/
:root {
    --bg: #060916;
    --panel: rgba(255, 255, 255, 0.06);
    --panel2: rgba(255, 255, 255, 0.03);
    --border: rgba(120, 220, 255, 0.22);
    --border2: rgba(255, 255, 255, 0.12);
    --text: rgba(235, 245, 255, 0.92);
    --muted: rgba(235, 245, 255, 0.72);
    --accent: #60a5fa;
    --accent2: #22d3ee;
    --glow: rgba(60, 180, 255, 0.45);
}


/* =========================
   HEADER
========================= */
header {
    display: flex;
    justify-content: space-between;
    align-items: center;

    background: rgba(17, 24, 39, 0.92);
    backdrop-filter: blur(10px);

    color: white;

    padding: 20px 60px;

    position: sticky;
    top: 0;
    z-index: 1000;

    box-shadow: 0 4px 18px rgba(0,0,0,0.08);
}

/* =========================
   LOGO
========================= */
.logo {
    font-size: 1.9rem;
    font-weight: bold;
    letter-spacing: 1px;
}

/* =========================
   NAVIGATION
========================= */
nav ul {
    list-style: none;
    display: flex;
    gap: 30px;
}

nav a {
    text-decoration: none;
    color: white;
    font-weight: 500;
    position: relative;

    transition: 0.3s ease;
}

/* Underline Hover Effect */
nav a::after {
    content: "";
    position: absolute;

    left: 0;
    bottom: -6px;

    width: 0%;
    height: 2px;

    background: #60a5fa;

    transition: width 0.3s ease;
}

nav a:hover::after {
    width: 100%;
}

nav a:hover {
    color: #60a5fa;
}

/* =========================
   HERO SECTION (High-tech)
========================= */
.hero {
    text-align: center;
    padding: 140px 20px;
    color: var(--text);
    background:
        radial-gradient(900px 380px at 50% 0%, rgba(34, 211, 238, 0.22), rgba(34, 211, 238, 0) 60%),
        linear-gradient(135deg, rgba(17,24,39,0.85), rgba(31,41,55,0.65), rgba(55,65,81,0.45));
    position: relative;
    overflow: hidden;
}

.hero::after {
    content: '';
    position: absolute;
    inset: 0;
    pointer-events: none;
    background:
        repeating-linear-gradient(
            0deg,
            rgba(120, 220, 255, 0.0) 0px,
            rgba(120, 220, 255, 0.0) 6px,
            rgba(120, 220, 255, 0.12) 7px
        );
    opacity: 0.18;
}

.hero-holo {
    margin: 0 auto;
    max-width: 900px;
    padding: 56px 34px;
    border-radius: 22px;

    background: linear-gradient(180deg, rgba(255,255,255,0.07), rgba(255,255,255,0.02));
    border: 1px solid rgba(120, 220, 255, 0.22);
    box-shadow:
        0 0 0 1px rgba(34, 211, 238, 0.08),
        0 20px 80px rgba(0,0,0,0.45);

    backdrop-filter: blur(10px);
    transform: translateZ(0);
}

.hero h1 {
    font-size: 3.8rem;
    margin-bottom: 18px;
    letter-spacing: 0.3px;

    animation: heroFade 1s ease;
}

.hero p {
    font-size: 1.2rem;
    opacity: 0.92;
    max-width: 780px;
    margin: auto;
    animation: heroFade 1.5s ease;
}

.hero-meta {

    display: flex;
    gap: 10px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 26px;
}

.chip {
    padding: 8px 12px;
    border-radius: 999px;
    border: 1px solid rgba(120, 220, 255, 0.22);
    background: rgba(255,255,255,0.04);
    color: rgba(235, 245, 255, 0.9);
    font-size: 0.92rem;
    box-shadow: 0 0 18px rgba(96,165,250,0.15);
}

@media (prefers-reduced-motion: reduce) {
    .hero, .hero h1, .hero p {
        animation: none !important;
    }
}


.hero p {
    max-width: 780px;
    margin: auto;

    font-size: 1.2rem;
    opacity: 0.92;

    animation: heroFade 1.5s ease;
}

/* =========================
   CONTENT SECTIONS (Holographic 3D panels)
========================= */
.content-section {
    padding: 90px 60px;

    margin: 50px auto;
    max-width: 1100px;

    border-radius: 18px;
    background: linear-gradient(180deg, rgba(255,255,255,0.06), rgba(255,255,255,0.025));
    border: 1px solid rgba(120, 220, 255, 0.22);

    box-shadow:
        0 0 0 1px rgba(34, 211, 238, 0.08),
        0 18px 60px rgba(0,0,0,0.35);

    position: relative;
    overflow: hidden;

    /* Scroll Position Fix */
    scroll-margin-top: 140px;

    /* Initial Hidden State */
    opacity: 0;
    transform:
        translateY(80px)
        translateZ(0)
        rotateX(10deg)
        scale(0.985);

    transition:
        opacity 1s ease,
        transform 1s ease;

    /* set by JS */
    --holo: 0;
    transform-origin: 50% 30%;
}


/* Visible State */
.content-section.show {
    opacity: 1;

    transform:
        translateY(0)
        rotateX(calc(var(--holo) * -6deg))
        scale(1);
}

.content-section::before {
    content: '';
    position: absolute;
    inset: -2px;
    background:
        radial-gradient(600px 180px at 20% 0%, rgba(34, 211, 238, 0.22), rgba(34, 211, 238, 0) 60%),
        radial-gradient(600px 180px at 80% 0%, rgba(96, 165, 250, 0.22), rgba(96, 165, 250, 0) 60%);
    opacity: calc(0.25 + var(--holo) * 0.75);
    pointer-events: none;
    transition: opacity 0.3s ease;
}

.content-section::after {
    content: '';
    position: absolute;
    inset: 0;
    background:
        repeating-linear-gradient(
            90deg,
            rgba(120, 220, 255, 0.0) 0px,
            rgba(120, 220, 255, 0.0) 22px,
            rgba(120, 220, 255, 0.18) 23px,
            rgba(120, 220, 255, 0.0) 24px
        );
    opacity: calc(0.08 + var(--holo) * 0.25);
    mix-blend-mode: screen;
    pointer-events: none;
    transform: translateZ(0);
}


/* =========================
   SECTION HEADINGS
========================= */
.content-section h2 {
    font-size: 2.3rem;

    margin-bottom: 24px;

    color: #1e3a8a;

    opacity: 0;

    transform: translateY(35px);

    transition:
        opacity 0.8s ease,
        transform 0.8s ease;
}

/* Heading Appears First */
.content-section.show h2 {
    opacity: 1;
    transform: translateY(0);
}

/* =========================
   PARAGRAPHS + LISTS
========================= */
.content-section p,
.content-section ul {

    opacity: 0;

    transform: translateY(25px);

    transition:
        opacity 1s ease,
        transform 1s ease;
}

/* Delayed Content Animation */
.content-section.show p,
.content-section.show ul {

    opacity: 1;

    transform: translateY(0);

    transition-delay: 0.35s;
}

/* =========================
   LISTS
========================= */
.content-section ul {
    padding-left: 20px;
}

.content-section li {
    margin-bottom: 12px;
}

/* =========================
   FOOTER
========================= */
footer {

    background: #111827;

    color: white;

    text-align: center;

    padding: 35px 20px;

    margin-top: 60px;
}

footer p {
    margin-bottom: 10px;
}

/* =========================
   HERO ANIMATION
========================= */
@keyframes heroFade {
    from {
        opacity: 0;
        transform: translateY(30px);
    }

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

@media (prefers-reduced-motion: reduce) {
    * {
        scroll-behavior: auto !important;
    }
}


/* =========================
   RESPONSIVE DESIGN
========================= */
@media (max-width: 768px) {

    header {
        flex-direction: column;
        gap: 18px;
        padding: 20px;
    }

    nav ul {
        flex-wrap: wrap;
        justify-content: center;
        gap: 16px;
    }

    .hero {
        padding: 110px 20px;
    }

    .hero h1 {
        font-size: 2.5rem;
    }

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

    .content-section {
        padding: 50px 25px;
        margin: 30px 15px;
    }

    .content-section h2 {
        font-size: 1.8rem;
    }
}