/* ============================================================
   2ndself — design system
   Dark-first, light-aware. One stylesheet for landing + docs.
   ============================================================ */

:root {
  /* palette — dark (default) */
  --bg:            #08080c;
  --bg-1:          #0d0d14;
  --bg-2:          #12121c;
  --surface:       #14141f;
  --surface-2:     #191926;
  --border:        rgba(255,255,255,0.08);
  --border-strong: rgba(255,255,255,0.14);
  --text:          #ecebf2;
  --text-2:        #b6b5c6;
  --text-3:        #86859a;
  --accent:        #8b7bff;
  --accent-2:      #22d3ee;
  --accent-soft:   rgba(139,123,255,0.14);
  --accent-line:   rgba(139,123,255,0.35);
  --code-bg:       #0c0c14;
  --code-border:   rgba(255,255,255,0.07);
  --good:          #4ade80;
  --warn:          #fbbf24;

  --grad: linear-gradient(120deg, #a78bff 0%, #8b7bff 40%, #34d3ee 100%);
  --grad-text: linear-gradient(120deg, #c4b5ff 0%, #8b7bff 45%, #34d3ee 100%);

  --maxw: 1120px;
  --sidebar: 264px;
  --radius: 14px;
  --radius-sm: 9px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, "Apple Color Emoji", sans-serif;
  --mono: "SFMono-Regular", ui-monospace, "JetBrains Mono", "Menlo", Consolas, monospace;
  --shadow: 0 20px 60px -20px rgba(0,0,0,0.7);
}

:root[data-theme="light"] {
  --bg:            #ffffff;
  --bg-1:          #fbfbfd;
  --bg-2:          #f5f5f9;
  --surface:       #ffffff;
  --surface-2:     #f7f7fb;
  --border:        rgba(10,10,25,0.09);
  --border-strong: rgba(10,10,25,0.16);
  --text:          #16161f;
  --text-2:        #45454f;
  --text-3:        #6d6d7a;
  --accent:        #6b5bff;
  --accent-2:      #0891b2;
  --accent-soft:   rgba(107,91,255,0.10);
  --accent-line:   rgba(107,91,255,0.30);
  --code-bg:       #f6f6fb;
  --code-border:   rgba(10,10,25,0.08);
  --good:          #16a34a;
  --warn:          #b45309;
  --grad-text: linear-gradient(120deg, #6b5bff 0%, #7c5cff 45%, #0891b2 100%);
  --shadow: 0 20px 50px -24px rgba(30,20,80,0.28);
}

@media (prefers-color-scheme: light) {
  :root:not([data-theme="dark"]) {
    --bg:#ffffff; --bg-1:#fbfbfd; --bg-2:#f5f5f9; --surface:#ffffff; --surface-2:#f7f7fb;
    --border:rgba(10,10,25,0.09); --border-strong:rgba(10,10,25,0.16);
    --text:#16161f; --text-2:#45454f; --text-3:#6d6d7a;
    --accent:#6b5bff; --accent-2:#0891b2; --accent-soft:rgba(107,91,255,0.10); --accent-line:rgba(107,91,255,0.30);
    --code-bg:#f6f6fb; --code-border:rgba(10,10,25,0.08); --good:#16a34a; --warn:#b45309;
    --grad-text:linear-gradient(120deg,#6b5bff 0%,#7c5cff 45%,#0891b2 100%);
    --shadow:0 20px 50px -24px rgba(30,20,80,0.28);
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.68;
  font-size: 16.5px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; text-underline-offset: 3px; }
::selection { background: var(--accent-soft); }

.grad-text {
  background: var(--grad-text);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
}

/* ---------- top nav ---------- */
.nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: saturate(1.6) blur(14px);
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: var(--maxw); margin: 0 auto; padding: 0 24px;
  height: 62px; display: flex; align-items: center; gap: 22px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 650; letter-spacing: -0.02em; color: var(--text); font-size: 1.06rem; }
.brand:hover { text-decoration: none; }
.brand .mark { width: 26px; height: 26px; flex: none; }
.nav-spacer { flex: 1; }
.nav-links { display: flex; align-items: center; gap: 20px; }
.nav-links a { color: var(--text-2); font-size: 0.94rem; font-weight: 500; }
.nav-links a:hover { color: var(--text); text-decoration: none; }
.theme-btn {
  display: inline-flex; align-items: center; justify-content: center;
  width: 34px; height: 34px; border-radius: 9px; cursor: pointer;
  background: var(--surface-2); border: 1px solid var(--border); color: var(--text-2);
}
.theme-btn:hover { color: var(--text); border-color: var(--border-strong); }
.theme-btn svg { width: 17px; height: 17px; }
.theme-btn .sun { display: none; }
:root[data-theme="light"] .theme-btn .sun { display: block; }
:root[data-theme="light"] .theme-btn .moon { display: none; }
@media (prefers-color-scheme: light) { :root:not([data-theme="dark"]) .theme-btn .sun{display:block;} :root:not([data-theme="dark"]) .theme-btn .moon{display:none;} }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 18px; border-radius: 10px; font-weight: 560; font-size: 0.95rem;
  border: 1px solid transparent; cursor: pointer; transition: transform .12s ease, box-shadow .2s ease;
}
.btn:hover { text-decoration: none; }
.btn-primary { color: #fff; background: linear-gradient(120deg, #8b7bff, #6b5bff); box-shadow: 0 8px 24px -8px rgba(123,92,255,0.7); }
.btn-primary:hover { transform: translateY(-1px); box-shadow: 0 12px 30px -8px rgba(123,92,255,0.8); }
.btn-ghost { color: var(--text); background: var(--surface-2); border-color: var(--border-strong); }
.btn-ghost:hover { border-color: var(--accent-line); }

/* ============================================================
   LANDING
   ============================================================ */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

.hero { position: relative; overflow: hidden; padding: 84px 0 72px; }
.hero-bg {
  position: absolute; inset: -40% -10% auto -10%; height: 720px; z-index: 0; pointer-events: none;
  background:
    radial-gradient(46% 40% at 22% 30%, rgba(139,123,255,0.30), transparent 70%),
    radial-gradient(40% 38% at 82% 20%, rgba(34,211,238,0.16), transparent 70%);
  filter: blur(10px); opacity: 0.9;
}
:root[data-theme="light"] .hero-bg { opacity: 0.7; }
@media (prefers-color-scheme: light){ :root:not([data-theme="dark"]) .hero-bg{opacity:.7;} }
.hero-grid {
  position: relative; z-index: 1;
  display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 48px; align-items: center;
}
.eyebrow {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 0.8rem; font-weight: 600; letter-spacing: 0.04em; text-transform: uppercase;
  color: var(--accent); background: var(--accent-soft);
  padding: 6px 12px; border-radius: 999px; border: 1px solid var(--accent-line);
}
.hero h1 {
  font-size: clamp(2.5rem, 5.4vw, 3.9rem); line-height: 1.04; letter-spacing: -0.035em;
  margin: 22px 0 0; font-weight: 700;
}
.hero .lede { font-size: 1.2rem; color: var(--text-2); margin: 22px 0 0; max-width: 34ch; }
.hero-cta { display: flex; gap: 14px; margin-top: 34px; flex-wrap: wrap; }
.hero-meta { margin-top: 26px; color: var(--text-3); font-size: 0.9rem; display: flex; gap: 18px; flex-wrap: wrap; }
.hero-meta span { display: inline-flex; align-items: center; gap: 7px; }
.dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); }

.hero-visual { position: relative; }
.hero-visual svg { width: 100%; height: auto; display: block; filter: drop-shadow(0 24px 60px rgba(80,60,200,0.28)); }

/* section shells */
.section { padding: 72px 0; border-top: 1px solid var(--border); }
.section-head { max-width: 62ch; }
.section-tag { font-size: 0.82rem; font-weight: 650; letter-spacing: 0.06em; text-transform: uppercase; color: var(--accent-2); }
.section h2 { font-size: clamp(1.7rem, 3.2vw, 2.3rem); letter-spacing: -0.03em; margin: 12px 0 0; line-height: 1.12; }
.section .sub { color: var(--text-2); font-size: 1.08rem; margin-top: 16px; }

.lead-para { font-size: 1.22rem; line-height: 1.6; color: var(--text); max-width: 40ch; letter-spacing: -0.01em; }
.lead-para .em { background: var(--grad-text); -webkit-background-clip:text; background-clip:text; -webkit-text-fill-color: transparent; font-weight: 600; }

/* contrast (old vs new) */
.contrast { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-top: 40px; }
.contrast .card { padding: 26px; border-radius: var(--radius); border: 1px solid var(--border); background: var(--surface); }
.contrast .old { color: var(--text-3); }
.contrast .old h3, .contrast .new h3 { margin: 0 0 14px; font-size: 0.82rem; letter-spacing: 0.08em; text-transform: uppercase; }
.contrast .old h3 { color: var(--text-3); }
.contrast .new { border-color: var(--accent-line); background: linear-gradient(180deg, var(--accent-soft), transparent 60%), var(--surface); }
.contrast .new h3 { color: var(--accent); }
.contrast ul { margin: 0; padding-left: 18px; }
.contrast li { margin: 9px 0; }
.contrast .new li { color: var(--text); }

/* idea cards */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 40px; }
.idea {
  padding: 26px 24px; border-radius: var(--radius); border: 1px solid var(--border);
  background: var(--surface); position: relative; overflow: hidden;
  transition: border-color .2s ease, transform .2s ease;
}
.idea:hover { border-color: var(--accent-line); transform: translateY(-2px); }
.idea .n { font-family: var(--mono); font-size: 0.85rem; color: var(--accent); font-weight: 600; }
.idea h3 { margin: 12px 0 8px; font-size: 1.12rem; letter-spacing: -0.01em; }
.idea p { margin: 0; color: var(--text-2); font-size: 0.96rem; }

/* pipeline */
.pipe { margin-top: 40px; border: 1px solid var(--border); border-radius: var(--radius); background: var(--surface); overflow: hidden; }
.pipe svg { width: 100%; height: auto; display: block; }

/* cta band */
.cta-band {
  margin: 0 auto; text-align: center; padding: 76px 24px;
  border-top: 1px solid var(--border);
}
.cta-band h2 { font-size: clamp(1.8rem, 3.6vw, 2.5rem); letter-spacing: -0.03em; margin: 0; }
.cta-band p { color: var(--text-2); font-size: 1.1rem; margin: 16px 0 30px; }

footer.site {
  border-top: 1px solid var(--border); padding: 34px 0; color: var(--text-3); font-size: 0.9rem;
}
footer.site .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; align-items: center; }

/* ============================================================
   DOCS
   ============================================================ */
.docs { max-width: var(--maxw); margin: 0 auto; display: grid; grid-template-columns: var(--sidebar) 1fr; gap: 0; align-items: start; }
.sidebar {
  position: sticky; top: 62px; align-self: start;
  height: calc(100vh - 62px); overflow-y: auto;
  padding: 30px 22px 60px; border-right: 1px solid var(--border);
}
.sidebar .group { margin-bottom: 22px; }
.sidebar .group-label { font-size: 0.72rem; letter-spacing: 0.09em; text-transform: uppercase; color: var(--text-3); font-weight: 650; margin: 0 0 10px; padding-left: 12px; }
.sidebar a {
  display: block; padding: 7px 12px; border-radius: 8px; color: var(--text-2);
  font-size: 0.93rem; font-weight: 480; line-height: 1.35;
}
.sidebar a:hover { color: var(--text); background: var(--surface-2); text-decoration: none; }
.sidebar a.active { color: var(--accent); background: var(--accent-soft); font-weight: 560; }

.doc-main { min-width: 0; padding: 44px 8px 90px; }
.doc-body { max-width: 760px; margin: 0 auto; padding: 0 28px; }
.doc-body h1 { font-size: 2.35rem; letter-spacing: -0.035em; line-height: 1.1; margin: 0 0 8px; }
.doc-body h2 { font-size: 1.5rem; letter-spacing: -0.02em; margin: 46px 0 14px; padding-top: 8px; }
.doc-body h3 { font-size: 1.16rem; letter-spacing: -0.01em; margin: 32px 0 10px; }
.doc-body p, .doc-body li { color: var(--text-2); }
.doc-body strong { color: var(--text); font-weight: 620; }
.doc-body ul, .doc-body ol { padding-left: 22px; }
.doc-body li { margin: 7px 0; }
.doc-body li::marker { color: var(--text-3); }
.doc-body blockquote {
  margin: 22px 0; padding: 4px 20px; border-left: 3px solid var(--accent-line);
  background: var(--accent-soft); border-radius: 0 8px 8px 0; color: var(--text);
}
.doc-body blockquote p { color: var(--text); }
.doc-body hr { border: none; border-top: 1px solid var(--border); margin: 40px 0; }

.doc-body code {
  font-family: var(--mono); font-size: 0.86em;
  background: var(--code-bg); border: 1px solid var(--code-border);
  padding: 1.5px 6px; border-radius: 6px; color: var(--text);
}
.doc-body pre {
  background: var(--code-bg); border: 1px solid var(--code-border);
  border-radius: 12px; padding: 18px 20px; overflow-x: auto; margin: 20px 0;
  font-size: 0.88rem; line-height: 1.6;
}
.doc-body pre code { background: none; border: none; padding: 0; font-size: 0.88rem; color: var(--text-2); }

.table-scroll { overflow-x: auto; margin: 22px 0; border: 1px solid var(--border); border-radius: 12px; }
.doc-body table { border-collapse: collapse; width: 100%; font-size: 0.92rem; }
.doc-body thead th { text-align: left; background: var(--surface-2); color: var(--text); font-weight: 620; }
.doc-body th, .doc-body td { padding: 11px 15px; border-bottom: 1px solid var(--border); vertical-align: top; }
.doc-body tbody tr:last-child td { border-bottom: none; }
.doc-body td { color: var(--text-2); }
.doc-body td code, .doc-body th code { white-space: nowrap; }

.eyebrow-doc { color: var(--accent-2); font-size: 0.8rem; font-weight: 650; letter-spacing: 0.07em; text-transform: uppercase; margin-bottom: 14px; }

.page-nav { display: flex; justify-content: space-between; gap: 16px; margin-top: 64px; padding-top: 26px; border-top: 1px solid var(--border); }
.page-nav a { display: block; padding: 16px 20px; border: 1px solid var(--border); border-radius: 12px; flex: 1; color: var(--text); background: var(--surface); }
.page-nav a:hover { border-color: var(--accent-line); text-decoration: none; }
.page-nav .lbl { font-size: 0.78rem; color: var(--text-3); text-transform: uppercase; letter-spacing: 0.05em; }
.page-nav .ttl { font-weight: 560; margin-top: 4px; }
.page-nav .next { text-align: right; }
.page-nav .spacer { flex: 1; }

/* mobile menu toggle */
.menu-btn { display: none; }
.sidebar-backdrop { display: none; }

@media (max-width: 900px) {
  .hero-grid { grid-template-columns: 1fr; gap: 30px; }
  .hero-visual { max-width: 440px; }
  .cards { grid-template-columns: 1fr; }
  .contrast { grid-template-columns: 1fr; }
  .docs { grid-template-columns: 1fr; }
  .menu-btn {
    display: inline-flex; align-items: center; gap: 8px; margin: 16px 0 0 20px;
    padding: 8px 14px; border: 1px solid var(--border); border-radius: 9px;
    background: var(--surface-2); color: var(--text); font-size: 0.9rem; cursor: pointer;
  }
  .sidebar {
    position: fixed; top: 0; left: 0; height: 100vh; width: 280px; z-index: 100;
    background: var(--bg-1); transform: translateX(-102%); transition: transform .22s ease;
    padding-top: 24px;
  }
  .sidebar.open { transform: translateX(0); }
  .sidebar-backdrop.show { display: block; position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 90; }
  .doc-body { padding: 0 20px; }
  .doc-body h1 { font-size: 1.9rem; }
}

/* ---------- svg diagrams (theme-aware) ---------- */
.dia-node   { fill: var(--surface-2); stroke: var(--border-strong); }
.dia-core   { fill: var(--accent-soft); stroke: var(--accent-line); }
.dia-line   { stroke: var(--border-strong); fill: none; }
.dia-flow   { stroke: var(--accent-line); fill: none; }
.dia-accent { fill: var(--accent); }
.dia-accent2{ fill: var(--accent-2); }
.dia-label  { fill: var(--text-2); font-family: var(--font); font-weight: 500; }
.dia-tag    { fill: var(--text-3); font-family: var(--mono); letter-spacing: 0.04em; }
.dia-strong { fill: var(--text); font-family: var(--font); font-weight: 600; }
.dia-dot    { fill: var(--text-3); }
.dia-dot-a  { fill: var(--accent); }