:root {
    --bg: #050505;
    --card: #0d0d0d;

    /* TEXT */
    --text: #f5f7fa; 
    --dim: #a1a7b3; 

    --border: #1f1f1f;

    /* ACCENTS */
    --neon-green: #3dff8f;
    --neon-blue: #4fdcff;
    --neon-orange: #ffb340;

    --font: "Google Sans Code Regular", monospace;
}

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

body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--font);
    line-height: 1.6;
    text-align: center;
}

.container-narrow {
    max-width: 750px;
    margin: 0 auto;
    padding: 0 20px;
}

.navbar {
    border-bottom: 1px solid var(--border);
    padding: 25px 0;
    background: var(--bg);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-content {
    max-width: 1000px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 40px;
}

.brand {
    font-weight: 800;
    letter-spacing: -1px;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-links a {
    text-decoration: none;
    color: var(--dim);
    font-size: 0.8rem;
    transition: 0.3s;
    position: relative;
}

.nav-links a::after {
    content: "";
    position: absolute;
    left: 0;
    bottom: -6px;
    width: 0;
    height: 1px;
    background: var(--neon-green);
    transition: width 0.3s ease;
}

.nav-links a:hover {
    color: var(--neon-green);
}

.nav-links a:hover::after {
    width: 100%;
}

.btn-git {
    text-decoration: none;
    border: 1px solid var(--neon-green);
    color: var(--neon-green);
    padding: 6px 18px;
    font-size: 0.75rem;
    font-weight: 700;
    border-radius: 4px;
    transition: 0.3s ease;
}

.btn-git:hover {
    background: rgba(0, 255, 102, 0.08);
    box-shadow: 0 0 12px rgba(0, 255, 102, 0.25);
}

/* HERO */
.hero {
    padding: 120px 0 80px;
}

.kicker {
    font-size: 0.7rem;
    color: var(--neon-green);
    letter-spacing: 3px;
    margin-bottom: 20px;
}

h1 {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: -2px;
    margin-bottom: 20px;
}

.hero p {
    color: var(--dim);
    font-size: 1rem;
}

.section {
    margin: 120px 0;
    text-align: left;
}

.section-title {
    font-size: 1.1rem;
    letter-spacing: 2px;
    color: var(--neon-green);
    margin-bottom: 20px;
}

.section p {
    color: var(--dim);
    margin-bottom: 16px;
    max-width: 65ch;
}

.diagram-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    margin: 40px 0;
}

.box {
    padding: 12px 30px;
    border: 1px solid var(--border);
    font-size: 0.8rem;
    background: var(--card);
    border-radius: 4px;
}

.box.blue {
    border-color: var(--neon-blue);
    color: var(--neon-blue);
    animation: kafkaPulse 3s infinite ease-in-out;
}

.box.gray {
    border-color: var(--dim);
    color: var(--dim);
}

@keyframes kafkaPulse {
    0%,
    100% {
        box-shadow: 0 0 0 rgba(0, 210, 255, 0);
    }
    50% {
        box-shadow: 0 0 16px rgba(0, 210, 255, 0.35);
    }
}

.diag-path {
    position: relative;
    height: 50px;
    width: 2px;
}

.line {
    height: 100%;
    width: 1px;
    background: var(--border);
    margin: 0 auto;
}

.particle {
    position: absolute;
    width: 4px;
    height: 4px;
    border-radius: 50%;
    left: -1.5px;
    animation: flow 2s infinite linear;
}

.p-blue {
    background: var(--neon-blue);
    box-shadow: 0 0 10px var(--neon-blue);
}

.p-orange {
    background: var(--neon-orange);
    box-shadow: 0 0 10px var(--neon-orange);
    animation-duration: 0.7s;
}

@keyframes flow {
    0% {
        top: 0;
    }
    100% {
        top: 100%;
    }
}

.spark-cluster {
    border: 1px solid var(--neon-orange);
    padding: 20px;
    width: 240px;
    background: var(--card);
    border-radius: 8px;
    color: var(--neon-orange);
}

.master {
    font-size: 0.7rem;
    border-bottom: 1px solid rgba(255, 157, 0, 0.2);
    margin-bottom: 12px;
    padding-bottom: 8px;
    letter-spacing: 1px;
}

.worker-grid {
    display: flex;
    justify-content: center;
    gap: 8px;
}

.w {
    width: 40px;
    height: 40px;
    border: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.6rem;
    color: var(--dim);
}

.w.dynamic {
    border-color: var(--neon-green);
    color: var(--neon-green);
    animation: scalePulse 4s infinite ease-in-out;
}

@keyframes scalePulse {
    0%,
    20% {
        opacity: 0;
        transform: scale(0.9);
    }
    40%,
    80% {
        opacity: 1;
        transform: scale(1);
    }
    100% {
        opacity: 0;
    }
}

.table-container {
    border: 1px solid var(--border);
    border-radius: 8px;
    overflow: hidden;
    margin: 20px 0;
}

.stack-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
    font-size: 0.8rem;
}

.stack-table th {
    background: #111;
    color: var(--dim);
    padding: 15px;
    text-transform: uppercase;
    font-size: 0.7rem;
}

.stack-table td {
    padding: 15px;
    border-top: 1px solid var(--border);
}

.row-blue td:first-child {
    color: var(--neon-blue);
    font-weight: 800;
}

.row-orange td:first-child {
    color: var(--neon-orange);
    font-weight: 800;
}

.row-green td:first-child {
    color: var(--neon-green);
    font-weight: 800;
}

.metrics-symmetrical {
    display: flex;
    justify-content: space-around;
    margin: 40px 0;
}

.metric {
    text-align: center;
    padding: 20px;
}

.val {
    display: block;
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -3px;
    transition: transform 0.3s ease;
}

.metric:hover .val {
    transform: scale(1.05);
}

.val.green {
    color: var(--neon-green);
}

.val.blue {
    color: var(--neon-blue);
}

.lab {
    font-size: 0.7rem;
    color: var(--dim);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.footer {
    padding: 80px 0;
    border-top: 1px solid var(--border);
    font-size: 0.7rem;
    color: var(--dim);
}

@media (prefers-reduced-motion: reduce) {
    * {
        animation: none !important;
        transition: none !important;
    }
}

@media (max-width: 768px) {
    h1 {
        font-size: 2.2rem;
    }

    .metrics-symmetrical {
        flex-direction: column;
        gap: 40px;
    }

    .nav-links {
        display: none;
    }

    .diagram-wrapper {
        gap: 30px;
    }
}