/* alt - FlatNine theme, dark + light. Design language lifted from
   flatnine-intelligence (same variables, nav, type scale), extended with the
   document styles the dataset pages need (cover, stat grid, spec tables). */

:root,
:root[data-theme="dark"] {
    --bg:      #0e0f12;
    --bg-2:    #15171c;
    --fg:      #e8e9ed;
    --muted:   #8a8f99;
    --accent:  #d8a657;
    --red:     #ea6962;
    --green:   #a9b665;
    --border:  #2a2d33;
    --card:    #15171c;
    --cover:   linear-gradient(160deg, #15171c 0%, #23262d 60%, #2a2d33 100%);
    --cover-fg: #e8e9ed;
    --logo-filter: invert(1) hue-rotate(180deg);
    --shadow: 0 1px 0 rgba(255, 255, 255, 0.04);
}

:root[data-theme="light"] {
    --bg:      #ffffff;
    --bg-2:    #f7f7f8;
    --fg:      #15171c;
    --muted:   #6b7280;
    --accent:  #9b111e;
    --red:     #c0392b;
    --green:   #6b8e23;
    --border:  #e5e7eb;
    --card:    #f5f5f6;
    --cover:   linear-gradient(160deg, #1a0a0c 0%, #6f0c15 55%, #9b111e 100%);
    --cover-fg: #ffffff;
    --logo-filter: none;
    --shadow: 0 1px 0 rgba(0, 0, 0, 0.04);
}

* { box-sizing: border-box; }
:focus-visible { outline: 2px solid #9b111e; outline-offset: 2px; }

html, body {
    background: var(--bg);
    color: var(--fg);
    font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-size: 14px;
    font-weight: 400;
    margin: 0;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

a { color: var(--fg); text-decoration: none; }
a:hover { color: var(--accent); }
.muted { color: var(--muted); }
code, .mono {
    font-family: 'SFMono-Regular', Menlo, Consolas, monospace;
}
code {
    background: var(--card);
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 0.92em;
}

/* ---- Nav (same chrome as intelligence) -------------------------------- */
.nav {
    border-bottom: 1px solid var(--border);
    padding: 14px 24px;
    display: flex;
    align-items: center;
    gap: 24px;
    max-width: 1200px;
    margin: 0 auto;
}
.brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 700;
    letter-spacing: 0.3px;
    color: var(--fg);
}
.brand-logo { height: 22px; width: auto; display: block; filter: var(--logo-filter); }
.brand-text { font-weight: 500; }
.nav-spacer { flex: 1; }
.langs { display: flex; border: 1px solid var(--border); border-radius: 4px; overflow: hidden; }
.langs a {
    font-family: Menlo, 'Courier New', monospace;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 1px;
    color: var(--muted);
    padding: 5px 9px;
    line-height: 1.2;
}
.langs a + a { border-left: 1px solid var(--border); }
.langs a:hover { color: var(--fg); }
.langs a[aria-current="true"] { background: var(--accent); color: var(--bg); }

.theme-toggle {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--muted);
    cursor: pointer;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    transition: color 0.15s, border-color 0.15s;
}
.theme-toggle:hover { color: var(--accent); border-color: var(--accent); }
.theme-toggle .theme-icon { line-height: 1; }
:root[data-theme="dark"]  .theme-toggle .light-icon { display: none; }
:root[data-theme="light"] .theme-toggle .dark-icon  { display: none; }

/* ---- Page shell -------------------------------------------------------- */
main { max-width: 1200px; margin: 0 auto; padding: 0 0 64px; }
section { padding: 48px 40px; border-bottom: 1px solid var(--border); }
section:last-child { border-bottom: 0; }

h1, h2, h3 { font-weight: 500; }
h1 { font-size: 2.1rem; letter-spacing: -0.02em; line-height: 1.15; margin: 0; }
h2 {
    font-size: 1.3rem;
    letter-spacing: -0.01em;
    margin: 0 0 18px;
}
h2 .eyebrow {
    display: block;
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 8px;
}
h3 { font-size: 0.98rem; font-weight: 700; margin: 22px 0 8px; }
p { color: var(--muted); margin: 0 0 12px; font-size: 0.95rem; }
p.lead { font-size: 1.05rem; color: var(--fg); font-weight: 400; }
p:last-child { margin-bottom: 0; }

/* ---- Cover ------------------------------------------------------------- */
.cover {
    background: var(--cover);
    color: var(--cover-fg);
    padding: 64px 40px;
    border-bottom: 1px solid var(--border);
}
.cover h1 { color: var(--cover-fg); max-width: 22ch; }
.cover .sub {
    margin-top: 16px;
    font-size: 1.05rem;
    color: var(--cover-fg);
    opacity: 0.82;
    max-width: 58ch;
}
.cover .meta {
    margin-top: 38px;
    display: flex;
    gap: 34px;
    flex-wrap: wrap;
    font-size: 0.84rem;
    color: var(--cover-fg);
    opacity: 0.72;
}
.cover .meta b {
    display: block;
    opacity: 1;
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 2px;
}
.badge {
    display: inline-block;
    background: rgba(255,255,255,.10);
    border: 1px solid rgba(255,255,255,.22);
    padding: 5px 12px;
    border-radius: 999px;
    font-size: 0.72rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    margin-bottom: 22px;
}
.backlink {
    display: inline-block;
    margin-bottom: 18px;
    font-size: 0.8rem;
    color: var(--cover-fg);
    opacity: 0.7;
}
.backlink:hover { opacity: 1; color: var(--cover-fg); }

/* ---- Stat grid --------------------------------------------------------- */
.grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1px;
    background: var(--border);
    border: 1px solid var(--border);
    border-radius: 6px;
    overflow: hidden;
}
.stat { background: var(--bg); padding: 22px 20px; }
.stat .n {
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: -0.02em;
}
.stat .l { font-size: 0.8rem; color: var(--muted); margin-top: 4px; }

/* ---- Cards, lists, pills ---------------------------------------------- */
.cat { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 8px; }
.card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 20px;
}
.card .k {
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 6px;
}
.card p { font-size: 0.9rem; }

ul.checks { list-style: none; margin: 6px 0 0; padding: 0; }
ul.checks li {
    position: relative;
    padding: 10px 0 10px 24px;
    border-bottom: 1px solid var(--border);
    color: var(--fg);
    font-size: 0.94rem;
}
ul.checks li:last-child { border-bottom: 0; }
ul.checks li::before {
    content: "";
    position: absolute;
    left: 2px;
    top: 17px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--accent);
}
ul.uc li { padding-left: 24px; }
.uc-tag {
    display: inline-block;
    min-width: 104px;
    font-weight: 700;
    font-size: 0.7rem;
    letter-spacing: 0.07em;
    text-transform: uppercase;
    color: var(--accent);
    vertical-align: baseline;
}

.pillrow { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; }
.pill {
    background: var(--card);
    color: var(--fg);
    border: 1px solid var(--border);
    padding: 4px 11px;
    border-radius: 999px;
    font-size: 0.8rem;
    font-weight: 500;
}

/* ---- Tables ------------------------------------------------------------ */
.table-wrap { overflow-x: auto; }
table { width: 100%; border-collapse: collapse; margin-top: 14px; font-size: 0.88rem; }
th, td { text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--border); vertical-align: top; }
th {
    background: var(--card);
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--muted);
    font-weight: 700;
}
td { color: var(--muted); }
td code { color: var(--fg); background: var(--card); }
.twocol-tables { display: grid; grid-template-columns: 1fr 1fr; gap: 26px; }

pre {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 14px 16px;
    overflow-x: auto;
    font-family: 'SFMono-Regular', Menlo, Consolas, monospace;
    font-size: 0.82rem;
    color: var(--fg);
    line-height: 1.5;
}
pre code { background: transparent; padding: 0; }

/* ---- Dataset index cards (home) --------------------------------------- */
.datasets { display: grid; grid-template-columns: repeat(2, 1fr); gap: 16px; }
.dataset {
    display: block;
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 22px;
    background: var(--bg);
    transition: border-color 0.15s, background 0.15s;
}
.dataset:hover { border-color: var(--accent); background: var(--card); color: var(--fg); }
.dataset .k {
    font-size: 0.68rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 8px;
}
.dataset h3 { margin: 0 0 6px; font-size: 1.02rem; font-weight: 500; }
.dataset p { margin: 0; font-size: 0.88rem; }
.dataset .figures {
    margin-top: 14px;
    padding-top: 12px;
    border-top: 1px solid var(--border);
    font-family: 'SFMono-Regular', Menlo, Consolas, monospace;
    font-size: 0.78rem;
    color: var(--muted);
}

/* ---- Contact / footer -------------------------------------------------- */
.cta {
    display: inline-block;
    border: 1px solid var(--accent);
    color: var(--accent);
    padding: 10px 18px;
    border-radius: 4px;
    font-weight: 500;
    margin-top: 6px;
}
.cta:hover { background: var(--accent); color: var(--bg); }
.foot {
    max-width: 1200px;
    margin: 0 auto;
    padding: 22px 40px 40px;
    font-size: 0.78rem;
    color: var(--muted);
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 10px;
    border-top: 1px solid var(--border);
}

@media (max-width: 860px) {
    .grid, .cat, .twocol-tables, .datasets { grid-template-columns: 1fr; }
}
@media (max-width: 760px) {
    .nav { padding: 10px 16px; gap: 10px; }
    .brand { flex: 1 1 auto; min-width: 0; }
    section, .cover, .foot { padding-left: 20px; padding-right: 20px; }
    .cover { padding-top: 44px; padding-bottom: 44px; }
    h1 { font-size: 1.7rem; }
}

/* Ported deck sections carry their old grouping classes (dp, dp1..dp5, api,
   meth, …). They no longer set their own palette - a single accent rule marks
   a new block instead. */
section.dp, section.dp1, section.dp2, section.dp3, section.dp4, section.dp5 {
    border-top: 2px solid var(--accent);
}

/* ---- API blocks (carried over from the deck's markup) ------------------ */
.endpoint {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 12px 14px;
    margin-top: 8px;
    font-family: 'SFMono-Regular', Menlo, Consolas, monospace;
    font-size: 0.86rem;
    flex-wrap: wrap;
}
.endpoint code { background: transparent; padding: 0; color: var(--fg); }
.verb {
    background: var(--accent);
    color: var(--bg);
    font-weight: 700;
    padding: 2px 8px;
    border-radius: 4px;
    font-size: 0.72rem;
    letter-spacing: 0.04em;
}
.desc {
    color: var(--muted);
    font-family: 'Roboto', sans-serif;
    font-size: 0.82rem;
    margin-left: auto;
}

pre.code {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 16px 18px;
    margin-top: 14px;
    font-family: 'SFMono-Regular', Menlo, Consolas, monospace;
    font-size: 0.8rem;
    line-height: 1.55;
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-word;
    color: var(--fg);
}
/* Syntax colours: comment / key / string / number. Kept legible on both
   the light and the dark card background. */
.code .c { color: var(--muted); }
.code .k { color: var(--accent); }
.code .s { color: var(--green); }
.code .n { color: var(--red); }

/* ---- Founders ---------------------------------------------------------- */
.founders { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; }
.founder { display: flex; gap: 18px; align-items: flex-start; }
.founder-photo {
    flex: 0 0 120px;
    width: 120px;
    height: 120px;
    border-radius: 6px;
    overflow: hidden;
    background: var(--card);
    border: 1px solid var(--border);
}
.founder-photo img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
    /* Colour arrives on hover, the way the portraits behave on flatnine.co. */
    filter: grayscale(100%);
    transition: filter .35s ease, transform .35s ease;
}
.founder:hover .founder-photo img { filter: grayscale(0%); transform: scale(1.03); }
.founder-name { font-size: 1rem; font-weight: 500; color: var(--fg); margin: 2px 0 2px; }
.founder-role {
    font-family: Menlo, 'Courier New', monospace;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--accent);
    margin-bottom: 8px;
}
.founder p { font-size: 0.9rem; margin: 0; }
@media (prefers-reduced-motion: reduce) {
    .founder-photo img { transition: none; }
    .founder:hover .founder-photo img { transform: none; }
}
@media (max-width: 860px) {
    .founders { grid-template-columns: 1fr; }
}