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

:root{
    --bg:#0a0e17;
    --surface:#111827;
    --surface2:#1e293b;
    --accent:#38bdf8;
    --accent2:#818cf8;
    --text:#e2e8f0;
    --muted:#64748b;
    --border:rgba(56,189,248,.15);
    --code-bg:#0d1117;
    --max-w:900px;
}

body{
    min-height:100vh;
    background:var(--bg);
    color:var(--text);
    font-family:'Segoe UI',system-ui,-apple-system,sans-serif;
    line-height:1.7;
    position:relative;
}

/* ── animated grid background ── */
.grid-bg{
    position:fixed;inset:0;z-index:0;
    background-image:
        linear-gradient(rgba(56,189,248,.04) 1px,transparent 1px),
        linear-gradient(90deg,rgba(56,189,248,.04) 1px,transparent 1px);
    background-size:48px 48px;
    animation:gridMove 20s linear infinite;
    pointer-events:none;
}
@keyframes gridMove{0%{background-position:0 0}100%{background-position:48px 48px}}

/* ── particles ── */
.particles{position:fixed;inset:0;z-index:0;pointer-events:none}
.particle{
    position:absolute;width:3px;height:3px;border-radius:50%;
    background:var(--accent);opacity:0;
    animation:float linear infinite;
}
@keyframes float{
    0%{opacity:0;transform:translateY(100vh) scale(0)}
    10%{opacity:.5}90%{opacity:.5}
    100%{opacity:0;transform:translateY(-10vh) scale(1)}
}

/* ── layout ── */
.site-header{
    position:sticky;top:0;z-index:100;
    background:rgba(10,14,23,.85);
    backdrop-filter:blur(12px);
    border-bottom:1px solid var(--border);
    padding:.75rem 1.5rem;
    display:flex;align-items:center;gap:1rem;
}
.site-header .logo{
    font-size:1.1rem;font-weight:700;
    background:linear-gradient(135deg,var(--accent),var(--accent2));
    -webkit-background-clip:text;-webkit-text-fill-color:transparent;
    background-clip:text;
    text-decoration:none;
    white-space:nowrap;
}
.site-header .archive-badge{
    display:inline-block;
    font-size:.6rem;
    font-weight:600;
    text-transform:uppercase;
    letter-spacing:.08em;
    padding:.15rem .5rem;
    margin-left:.5rem;
    border-radius:999px;
    border:1px solid rgba(129,140,248,.4);
    background:rgba(129,140,248,.12);
    color:var(--accent2);
    text-decoration:none;
    vertical-align:middle;
    transition:all .2s;
}
.site-header .archive-badge:hover{
    background:rgba(129,140,248,.25);
    border-color:var(--accent2);
}
.site-header nav{display:flex;gap:.5rem;flex-wrap:wrap}
.site-header nav a{
    color:var(--muted);font-size:.85rem;text-decoration:none;
    padding:.25rem .6rem;border-radius:6px;
    transition:all .2s;
}
.site-header nav a:hover,
.site-header nav a.active{
    color:var(--accent);background:rgba(56,189,248,.08);
}

.page-wrapper{
    position:relative;z-index:1;
    max-width:var(--max-w);
    margin:0 auto;
    padding:2rem 1.5rem 4rem;
}

/* ── breadcrumb ── */
.breadcrumb{
    font-size:.8rem;color:var(--muted);
    margin-bottom:1.5rem;
}
.breadcrumb a{color:var(--accent);text-decoration:none}
.breadcrumb a:hover{text-decoration:underline}
.breadcrumb .sep{margin:0 .4rem;opacity:.5}

/* ── article header ── */
.article-header{
    margin-bottom:2rem;
    padding-bottom:1.5rem;
    border-bottom:1px solid var(--border);
}
.article-header h1{
    font-size:clamp(1.6rem,4vw,2.4rem);
    font-weight:700;
    letter-spacing:-.02em;
    line-height:1.2;
    margin-bottom:.5rem;
}
.article-header h1 span{
    background:linear-gradient(135deg,var(--accent),var(--accent2));
    -webkit-background-clip:text;-webkit-text-fill-color:transparent;
    background-clip:text;
}
.article-meta{
    display:flex;flex-wrap:wrap;gap:.6rem;
    margin-top:.75rem;
}
.article-meta .tag{
    padding:.2rem .65rem;border-radius:999px;
    font-size:.75rem;font-weight:500;
    border:1px solid rgba(56,189,248,.2);
    background:rgba(56,189,248,.06);
    color:var(--accent);
}

/* ── article body ── */
.article-body h2{
    font-size:1.35rem;font-weight:600;
    margin:2.5rem 0 1rem;
    padding-bottom:.4rem;
    border-bottom:1px solid var(--border);
    color:var(--text);
}
.article-body h3{
    font-size:1.1rem;font-weight:600;
    margin:1.5rem 0 .75rem;
    color:var(--text);
}
.article-body p{
    margin-bottom:1rem;
    color:var(--text);
}
.article-body ul,.article-body ol{
    margin:0 0 1rem 1.5rem;
}
.article-body li{
    margin-bottom:.4rem;
}
.article-body a{
    color:var(--accent);text-decoration:none;
}
.article-body a:hover{text-decoration:underline}

/* ── images ── */
.article-body img{
    max-width:100%;height:auto;
    border-radius:8px;
    border:1px solid var(--border);
    margin:1rem 0;
}
.figure{
    margin:1.5rem 0;
    text-align:center;
}
.figure img{
    max-width:100%;height:auto;
    border-radius:8px;
    border:1px solid var(--border);
}
.figure figcaption,.figure .caption{
    font-size:.8rem;color:var(--muted);
    margin-top:.5rem;font-style:italic;
}
.thumb-right{
    float:right;
    margin:0 0 1rem 1.5rem;
    max-width:200px;
}
@media(max-width:600px){
    .thumb-right{float:none;max-width:100%;margin:1rem 0}
}

/* ── code blocks ── */
.code-block{
    background:var(--code-bg);
    border:1px solid var(--border);
    border-radius:12px;
    margin:1.5rem 0;
    overflow:hidden;
}
.code-block-header{
    display:flex;align-items:center;gap:6px;
    padding:.75rem 1rem;
    background:rgba(56,189,248,.04);
    border-bottom:1px solid var(--border);
    font-size:.75rem;color:var(--muted);
}
.code-block-header .dot{width:10px;height:10px;border-radius:50%}
.code-block-header .dot.r{background:#ef4444}
.code-block-header .dot.y{background:#eab308}
.code-block-header .dot.g{background:#22c55e}
.code-block-header .lang{color:var(--accent);font-weight:500}
.code-block-header .copy-btn{
    margin-left:auto;
    padding:.3rem .7rem;
    border:1px solid var(--border);
    border-radius:6px;
    background:transparent;
    color:var(--muted);
    font-size:.75rem;
    font-family:inherit;
    cursor:pointer;
    transition:all .2s;
}
.code-block-header .copy-btn:hover{
    color:var(--accent);border-color:var(--accent);
    background:rgba(56,189,248,.1);
    cursor:pointer;
}
.code-block-header .copy-btn:active{
    transform:scale(.95);
}
.code-block-header .copy-btn.copied{
    color:#34d399;border-color:#34d399;
    cursor:default;
}
.code-block pre{
    padding:1rem 1.25rem;
    overflow-x:auto;
    font-family:'Cascadia Code','Fira Code','SF Mono',monospace;
    font-size:.82rem;
    line-height:1.7;
    color:var(--text);
}
.code-block pre .comment{color:var(--muted);font-style:italic}
.code-block pre .keyword{color:var(--accent2)}
.code-block pre .string{color:#34d399}
.code-block pre .type{color:#f472b6}

/* ── info card (for download, notes, etc.) ── */
.info-card{
    background:var(--surface);
    border:1px solid var(--border);
    border-radius:12px;
    padding:1.25rem 1.5rem;
    margin:1.5rem 0;
}
.info-card h3{
    font-size:1rem;font-weight:600;
    margin:0 0 .75rem;
    color:var(--accent);
}
.info-card ul{margin-left:1.2rem}

/* ── video embed ── */
.video-wrapper{
    position:relative;
    padding-bottom:56.25%;
    margin:1.5rem 0;
    border-radius:12px;
    overflow:hidden;
    border:1px solid var(--border);
}
.video-wrapper iframe{
    position:absolute;top:0;left:0;
    width:100%;height:100%;
    border:none;
}

/* ── table of contents ── */
.toc{
    background:var(--surface);
    border:1px solid var(--border);
    border-radius:12px;
    padding:1.25rem 1.5rem;
    margin-bottom:2rem;
}
.toc h3{
    font-size:.9rem;font-weight:600;
    text-transform:uppercase;
    letter-spacing:.05em;
    color:var(--muted);
    margin-bottom:.75rem;
}
.toc ol{
    margin:0;padding-left:1.2rem;
    list-style:decimal;
}
.toc li{margin-bottom:.35rem;font-size:.9rem}
.toc a{color:var(--accent);text-decoration:none}
.toc a:hover{text-decoration:underline}

/* ── project listing (index page) ── */
.project-grid{
    display:grid;
    grid-template-columns:repeat(auto-fill,minmax(280px,1fr));
    gap:1.25rem;
    margin:1.5rem 0;
}
.project-card{
    background:var(--surface);
    border:1px solid var(--border);
    border-radius:12px;
    overflow:hidden;
    transition:all .25s;
    text-decoration:none;
    color:inherit;
    display:flex;flex-direction:column;
}
.project-card:hover{
    border-color:var(--accent);
    box-shadow:0 0 20px rgba(56,189,248,.1);
    transform:translateY(-2px);
}
.project-card img{
    width:100%;height:160px;
    object-fit:cover;
    border-bottom:1px solid var(--border);
}
.project-card .card-body{padding:1rem}
.project-card h3{
    font-size:1rem;font-weight:600;
    margin-bottom:.4rem;
    color:var(--text);
}
.project-card p{
    font-size:.85rem;color:var(--muted);
    line-height:1.5;
}
.project-card .card-tags{
    padding:.5rem 1rem .75rem;
    display:flex;gap:.4rem;flex-wrap:wrap;
    margin-top:auto;
}
.project-card .card-tags span{
    font-size:.7rem;padding:.15rem .5rem;
    border-radius:999px;
    background:rgba(56,189,248,.06);
    border:1px solid rgba(56,189,248,.15);
    color:var(--accent);
}

/* ── footer ── */
.site-footer{
    position:relative;z-index:1;
    text-align:center;
    padding:2rem 1rem;
    color:var(--muted);font-size:.8rem;
    border-top:1px solid var(--border);
    margin-top:4rem;
}
.site-footer a{color:var(--accent);text-decoration:none}
.site-footer a:hover{text-decoration:underline}

/* ── responsive ── */
@media(max-width:768px){
    .site-header{flex-direction:column;align-items:flex-start}
    .page-wrapper{padding:1.5rem 1rem 3rem}
    .project-grid{grid-template-columns:1fr}
}