/* ==========================================================================
   NexoPay TP — Gestión Integral de la Seguridad de la Información
   Dark cybersecurity aesthetic. Mobile-first. Responsive.
   ========================================================================== */

:root {
  --bg-0: #0a0f1a;          /* deepest background */
  --bg-1: #0f1623;          /* page background */
  --bg-2: #151d2e;          /* card background */
  --bg-3: #1c2640;          /* elevated card / hover */
  --bg-grid: #131c2e;       /* heatmap empty cell */
  --border: #243049;
  --border-soft: #1e283f;
  --text: #e6edf7;
  --text-dim: #9fb0c9;
  --text-mute: #6b7c99;
  --accent: #2dd4bf;        /* teal/cyan accent */
  --accent-2: #22d3ee;      /* cyan */
  --accent-glow: rgba(45, 212, 191, 0.18);
  --critico: #ef4444;       /* red */
  --alto: #f97316;          /* orange */
  --medio: #eab308;         /* yellow */
  --bajo: #22c55e;          /* green */
  --critico-bg: rgba(239, 68, 68, 0.14);
  --alto-bg: rgba(249, 115, 22, 0.14);
  --medio-bg: rgba(234, 179, 8, 0.14);
  --bajo-bg: rgba(34, 197, 94, 0.14);
  --mono: "JetBrains Mono", "Fira Code", "SFMono-Regular", Consolas, monospace;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --radius: 10px;
  --shadow: 0 4px 24px rgba(0, 0, 0, 0.35);
  --nav-h: 58px;
  --sidebar-w: 268px;
}

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

html { scroll-behavior: smooth; scroll-padding-top: calc(var(--nav-h) + 18px); }

body {
  font-family: var(--sans);
  background: var(--bg-1);
  color: var(--text);
  line-height: 1.65;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  overflow-x: hidden;
}

/* subtle grid backdrop */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(45, 212, 191, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(45, 212, 191, 0.025) 1px, transparent 1px);
  background-size: 44px 44px;
  pointer-events: none;
  z-index: 0;
}

/* ==========================================================================
   Top navigation
   ========================================================================== */
.topnav {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: rgba(10, 15, 26, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  padding: 0 18px;
  z-index: 100;
  gap: 14px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1rem;
  color: var(--text);
  white-space: nowrap;
}
.brand .logo {
  width: 30px; height: 30px;
  border-radius: 7px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  display: grid; place-items: center;
  color: var(--bg-0);
  font-weight: 800;
  font-family: var(--mono);
  font-size: 0.85rem;
  box-shadow: 0 0 16px var(--accent-glow);
}
.brand small { display: block; font-size: 0.62rem; color: var(--text-mute); font-weight: 500; letter-spacing: 0.04em; }

.nav-links {
  display: flex;
  gap: 4px;
  margin-left: auto;
}
.nav-links a {
  color: var(--text-dim);
  text-decoration: none;
  font-size: 0.86rem;
  font-weight: 500;
  padding: 8px 13px;
  border-radius: 7px;
  transition: all 0.18s ease;
  white-space: nowrap;
}
.nav-links a:hover { color: var(--text); background: var(--bg-3); }
.nav-links a.active {
  color: var(--accent);
  background: var(--accent-glow);
  box-shadow: inset 0 0 0 1px rgba(45, 212, 191, 0.35);
}

.hamburger {
  display: none;
  margin-left: auto;
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
  width: 40px; height: 40px;
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
}
.hamburger span {
  display: block;
  width: 20px; height: 2px;
  background: var(--accent);
  transition: 0.25s;
}
.hamburger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.hamburger.open span:nth-child(2) { opacity: 0; }
.hamburger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ==========================================================================
   Layout
   ========================================================================== */
.layout {
  display: grid;
  grid-template-columns: var(--sidebar-w) 1fr;
  margin-top: var(--nav-h);
  position: relative;
  z-index: 1;
}

.sidebar {
  position: sticky;
  top: var(--nav-h);
  height: calc(100vh - var(--nav-h));
  overflow-y: auto;
  background: var(--bg-0);
  border-right: 1px solid var(--border);
  padding: 22px 14px;
}
.sidebar h3 {
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-mute);
  margin: 18px 10px 8px;
  font-weight: 600;
}
.sidebar h3:first-child { margin-top: 0; }
.sidebar a {
  display: block;
  color: var(--text-dim);
  text-decoration: none;
  font-size: 0.86rem;
  padding: 7px 12px;
  border-radius: 7px;
  margin-bottom: 2px;
  border-left: 2px solid transparent;
  transition: all 0.15s;
}
.sidebar a:hover { color: var(--text); background: var(--bg-2); }
.sidebar a.active {
  color: var(--accent);
  background: var(--accent-glow);
  border-left-color: var(--accent);
}
.sidebar a.sub { padding-left: 26px; font-size: 0.8rem; color: var(--text-mute); }

.content { padding: 30px 38px 80px; min-width: 0; max-width: 1180px; }

/* ==========================================================================
   Typography & sections
   ========================================================================== */
section { margin-bottom: 56px; scroll-margin-top: calc(var(--nav-h) + 18px); }
section .sub { margin-bottom: 38px; }

h1, h2, h3, h4 { line-height: 1.25; font-weight: 700; letter-spacing: -0.01em; }
h2 {
  font-size: clamp(1.5rem, 4vw, 2.1rem);
  margin-bottom: 8px;
  color: var(--text);
}
h2 .tag {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--accent);
  background: var(--accent-glow);
  padding: 3px 9px;
  border-radius: 5px;
  margin-right: 10px;
  vertical-align: middle;
  font-weight: 600;
  letter-spacing: 0.05em;
}
h3 {
  font-size: 1.22rem;
  margin: 28px 0 10px;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 9px;
}
h3::before {
  content: "";
  width: 4px; height: 19px;
  background: linear-gradient(var(--accent), var(--accent-2));
  border-radius: 3px;
  flex-shrink: 0;
}
h4 { font-size: 1.02rem; margin: 20px 0 8px; color: var(--accent-2); }

p { margin-bottom: 14px; color: var(--text); }
p.lede { color: var(--text-dim); font-size: 1.05rem; }

a { color: var(--accent); }
strong { color: #fff; font-weight: 600; }
em { color: var(--accent-2); font-style: italic; }

ul, ol { margin: 0 0 16px 22px; color: var(--text); }
li { margin-bottom: 7px; }
li::marker { color: var(--accent); }

hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 34px 0;
}

code {
  font-family: var(--mono);
  font-size: 0.86em;
  background: var(--bg-3);
  color: var(--accent-2);
  padding: 2px 6px;
  border-radius: 4px;
}

/* ==========================================================================
   Cards & callouts
   ========================================================================== */
.card {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 22px;
  margin: 16px 0;
  box-shadow: var(--shadow);
}
.card.elevated { background: var(--bg-3); }

.callout {
  background: linear-gradient(180deg, var(--bg-2), var(--bg-1));
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius);
  padding: 16px 20px;
  margin: 16px 0;
}
.callout.warn { border-left-color: var(--medio); }
.callout.danger { border-left-color: var(--critico); }
.callout.info { border-left-color: var(--accent-2); }
.callout p:last-child { margin-bottom: 0; }
.callout .label {
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  display: block;
  margin-bottom: 6px;
}

/* Formula callout box */
.formula-box {
  background: linear-gradient(180deg, #0c1320, #0a0f1a);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
  margin: 18px 0;
  box-shadow: var(--shadow);
}
.formula-box .formula-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 10px;
}
.formula-box .formula-name {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: 0.04em;
}
.formula-box .formula-src {
  font-size: 0.68rem;
  color: var(--text-mute);
  font-family: var(--mono);
}
.formula-box .formula-render {
  background: rgba(45, 212, 191, 0.05);
  border: 1px solid var(--border-soft);
  border-radius: 8px;
  padding: 16px 12px;
  margin: 8px 0 12px;
  overflow-x: auto;
  text-align: center;
}
.formula-box .formula-render .katex-display { margin: 0; }
.formula-box .formula-vars {
  font-size: 0.82rem;
  color: var(--text-dim);
  border-top: 1px dashed var(--border);
  padding-top: 10px;
}
.formula-box .formula-vars ul { margin: 6px 0 0 18px; }
.formula-box .formula-vars li { margin-bottom: 3px; }
.formula-box .formula-vars strong { color: var(--accent-2); }

/* ==========================================================================
   Tables
   ========================================================================== */
.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin: 16px 0;
  background: var(--bg-2);
  -webkit-overflow-scrolling: touch;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.86rem;
  min-width: 100%;
}
thead th {
  position: sticky;
  top: 0;
  background: var(--bg-3);
  color: var(--accent);
  text-align: left;
  padding: 11px 13px;
  font-weight: 600;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
  z-index: 2;
}
tbody td {
  padding: 10px 13px;
  border-bottom: 1px solid var(--border-soft);
  color: var(--text);
  vertical-align: top;
}
tbody tr:nth-child(even) { background: rgba(28, 38, 64, 0.35); }
tbody tr:hover { background: var(--bg-3); }
tbody tr:last-child td { border-bottom: none; }

td .id, td.id {
  font-family: var(--mono);
  color: var(--accent-2);
  font-weight: 600;
  white-space: nowrap;
}

/* level badges */
.lvl { display: inline-block; padding: 2px 9px; border-radius: 5px; font-size: 0.72rem; font-weight: 700; letter-spacing: 0.04em; font-family: var(--mono); white-space: nowrap; }
.lvl-critico { background: var(--critico-bg); color: var(--critico); border: 1px solid rgba(239,68,68,0.4); }
.lvl-alto    { background: var(--alto-bg);    color: var(--alto);    border: 1px solid rgba(249,115,22,0.4); }
.lvl-medio   { background: var(--medio-bg);   color: var(--medio);   border: 1px solid rgba(234,179,8,0.4); }
.lvl-bajo    { background: var(--bajo-bg);    color: var(--bajo);    border: 1px solid rgba(34,197,94,0.4); }

.risk-row { cursor: pointer; transition: background 0.15s; }
.risk-row.selected { background: var(--accent-glow) !important; box-shadow: inset 3px 0 0 var(--accent); }

/* ==========================================================================
   Hero
   ========================================================================== */
.hero {
  position: relative;
  padding: 52px 0 40px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 44px;
}
.hero .eyebrow {
  font-family: var(--mono);
  font-size: 0.76rem;
  color: var(--accent);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  margin-bottom: 14px;
}
.hero h1 {
  font-size: clamp(1.9rem, 5.5vw, 3rem);
  line-height: 1.1;
  margin-bottom: 18px;
  background: linear-gradient(120deg, #fff 30%, var(--accent) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero .subtitle { font-size: 1.08rem; color: var(--text-dim); max-width: 640px; margin-bottom: 26px; }
.hero .meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
  margin-top: 22px;
}
.hero .meta-item {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 16px;
}
.hero .meta-item .k { font-size: 0.68rem; color: var(--text-mute); text-transform: uppercase; letter-spacing: 0.08em; }
.hero .meta-item .v { font-size: 1.05rem; color: var(--text); font-weight: 600; margin-top: 2px; }

.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 14px;
  margin: 22px 0;
}
.stat {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
  text-align: center;
}
.stat .num {
  font-family: var(--mono);
  font-size: 1.7rem;
  font-weight: 700;
  color: var(--accent);
  display: block;
}
.stat .lbl { font-size: 0.76rem; color: var(--text-mute); margin-top: 4px; }

/* ==========================================================================
   Charts
   ========================================================================== */
.chart-card {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
  margin: 16px 0;
  box-shadow: var(--shadow);
}
.chart-card .chart-title {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.chart-card .chart-title::before {
  content: "▤"; color: var(--accent); font-size: 0.8rem;
}
.chart-card .chart-desc { font-size: 0.8rem; color: var(--text-mute); margin-bottom: 14px; }
.chart-canvas-wrap { position: relative; height: 340px; }
.chart-canvas-wrap.tall { height: 420px; }
.chart-canvas-wrap.doughnut { height: 300px; }

/* ==========================================================================
   Heat map
   ========================================================================== */
.heatmaps { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; margin: 18px 0; }
.heatmap-card {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  box-shadow: var(--shadow);
}
.heatmap-card h4 { margin-top: 0; text-align: center; }
.heatmap {
  display: grid;
  grid-template-columns: 34px repeat(5, 1fr);
  grid-template-rows: repeat(5, 1fr) 24px;
  gap: 4px;
  aspect-ratio: 1 / 1;
}
.heatmap .hcell {
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 0.95rem;
  color: #fff;
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
  position: relative;
  min-height: 0;
}
.heatmap .hcell:hover { transform: scale(1.06); z-index: 3; box-shadow: 0 0 0 2px var(--accent); }
.heatmap .hcell.empty { color: var(--text-mute); }
.heatmap .hcell.hl { box-shadow: 0 0 0 3px var(--accent), 0 0 18px var(--accent-glow); z-index: 4; transform: scale(1.08); }
.heatmap .hlabel {
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono); font-size: 0.72rem; color: var(--text-mute);
}
.heatmap .hcorner { }
.hm-sev-critico { background: rgba(239,68,68,0.85); }
.hm-sev-alto    { background: rgba(249,115,22,0.85); }
.hm-sev-medio   { background: rgba(234,179,8,0.85); color: #1a1a1a; }
.hm-sev-bajo    { background: rgba(34,197,94,0.82); }
.hm-sev-none    { background: var(--bg-grid); }

.heatmap-legend { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 12px; justify-content: center; font-size: 0.74rem; color: var(--text-dim); }
.heatmap-legend span { display: inline-flex; align-items: center; gap: 5px; }
.heatmap-legend i { width: 12px; height: 12px; border-radius: 3px; display: inline-block; }

.heatmap-tooltip {
  position: fixed;
  background: var(--bg-0);
  border: 1px solid var(--accent);
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 0.78rem;
  color: var(--text);
  pointer-events: none;
  z-index: 200;
  box-shadow: var(--shadow);
  max-width: 280px;
  display: none;
}
.heatmap-tooltip strong { color: var(--accent); }
.heatmap-tooltip .tt-id { font-family: var(--mono); color: var(--accent-2); }

/* axis titles */
.hm-axis-y, .hm-axis-x {
  font-family: var(--mono);
  font-size: 0.66rem;
  color: var(--text-mute);
  text-align: center;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin: 6px 0;
}

/* ==========================================================================
   Metrics dashboard
   ========================================================================== */
.metrics-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; margin: 18px 0; }
.metric {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 16px;
}
.metric .m-head { display: flex; justify-content: space-between; align-items: baseline; margin-bottom: 6px; }
.metric .m-name { font-size: 0.88rem; font-weight: 600; color: var(--text); }
.metric .m-type { font-size: 0.62rem; font-family: var(--mono); padding: 2px 7px; border-radius: 4px; letter-spacing: 0.05em; }
.metric .m-type.kpi { background: var(--bajo-bg); color: var(--bajo); }
.metric .m-type.kri { background: var(--critico-bg); color: var(--critico); }
.metric .m-target { font-size: 0.76rem; color: var(--text-mute); margin-bottom: 10px; }
.metric .m-bar { height: 10px; background: var(--bg-grid); border-radius: 5px; overflow: hidden; position: relative; }
.metric .m-fill { height: 100%; border-radius: 5px; transition: width 1s ease; }
.metric .m-fill.good { background: linear-gradient(90deg, var(--bajo), var(--accent)); }
.metric .m-fill.warn { background: linear-gradient(90deg, var(--medio), var(--alto)); }
.metric .m-fill.bad  { background: linear-gradient(90deg, var(--alto), var(--critico)); }
.metric .m-val { font-family: var(--mono); font-size: 0.92rem; color: var(--accent-2); margin-top: 8px; font-weight: 600; }
.metric .m-origin { font-size: 0.68rem; color: var(--text-mute); margin-top: 6px; font-family: var(--mono); }

/* gauge */
.gauge { position: relative; width: 100%; height: 110px; }
.gauge svg { width: 100%; height: 100%; }

/* ==========================================================================
   Timeline
   ========================================================================== */
.timeline { position: relative; margin: 24px 0; padding-left: 28px; }
.timeline::before {
  content: ""; position: absolute; left: 8px; top: 4px; bottom: 4px;
  width: 2px; background: linear-gradient(var(--accent), var(--accent-2), var(--critico));
}
.tl-item { position: relative; margin-bottom: 22px; }
.tl-item::before {
  content: ""; position: absolute; left: -25px; top: 4px;
  width: 14px; height: 14px; border-radius: 50%;
  background: var(--bg-1);
  border: 3px solid var(--accent);
  box-shadow: 0 0 10px var(--accent-glow);
}
.tl-item.danger::before { border-color: var(--critico); box-shadow: 0 0 10px rgba(239,68,68,0.4); }
.tl-item.warn::before { border-color: var(--medio); }
.tl-item .tl-time { font-family: var(--mono); font-size: 0.7rem; color: var(--text-mute); letter-spacing: 0.04em; }
.tl-item .tl-title { font-weight: 600; color: var(--text); font-size: 0.96rem; margin: 2px 0 4px; }
.tl-item .tl-desc { font-size: 0.84rem; color: var(--text-dim); }

/* horizontal timeline (incident flow) */
.flow {
  display: flex;
  overflow-x: auto;
  gap: 0;
  padding: 18px 4px;
  margin: 18px 0;
  scroll-snap-type: x mandatory;
}
.flow-step {
  flex: 0 0 auto;
  min-width: 168px;
  max-width: 200px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px;
  scroll-snap-align: start;
  position: relative;
}
.flow-step + .flow-step { margin-left: 22px; }
.flow-step + .flow-step::before {
  content: "→"; position: absolute; left: -20px; top: 50%;
  transform: translateY(-50%); color: var(--accent); font-weight: 700;
}
.flow-step .fs-num {
  font-family: var(--mono); font-size: 0.7rem; color: var(--accent);
  background: var(--accent-glow); padding: 2px 7px; border-radius: 4px;
  display: inline-block; margin-bottom: 8px;
}
.flow-step .fs-title { font-weight: 600; font-size: 0.88rem; margin-bottom: 4px; color: var(--text); }
.flow-step .fs-desc { font-size: 0.76rem; color: var(--text-dim); }

/* ==========================================================================
   PDCA diagram
   ========================================================================== */
.pdca-wrap { display: grid; grid-template-columns: 1fr; gap: 22px; margin: 18px 0; }
@media (min-width: 760px) { .pdca-wrap { grid-template-columns: 340px 1fr; } }
.pdca-svg { width: 100%; max-width: 340px; margin: 0 auto; }
.pdca-phase { cursor: pointer; transition: opacity 0.2s; }
.pdca-phase:hover { opacity: 0.88; }
.pdca-phase.dim { opacity: 0.35; }
.pdca-details { background: var(--bg-2); border: 1px solid var(--border); border-radius: 10px; padding: 18px; min-height: 200px; }
.pdca-details h4 { margin-top: 0; color: var(--accent); }
.pdca-details .pd-tag { font-family: var(--mono); font-size: 0.7rem; color: var(--text-mute); }
.pdca-details .pd-body { font-size: 0.9rem; color: var(--text-dim); margin-top: 8px; }
.pdca-details .pd-eg { font-size: 0.84rem; color: var(--accent-2); margin-top: 10px; font-style: italic; }

/* ==========================================================================
   Incident badge / status
   ========================================================================== */
.incident-banner {
  background: linear-gradient(135deg, rgba(239,68,68,0.12), rgba(249,115,22,0.08));
  border: 1px solid rgba(239,68,68,0.4);
  border-radius: 12px;
  padding: 22px 24px;
  margin: 18px 0;
}
.incident-banner .ib-tag {
  font-family: var(--mono); font-size: 0.72rem; color: var(--critico);
  letter-spacing: 0.1em; text-transform: uppercase; margin-bottom: 6px;
}
.incident-banner h3 { color: #fff; margin-top: 0; }
.incident-banner h3::before { display: none; }

/* chips */
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 10px 0; }
.chip {
  font-size: 0.74rem; font-family: var(--mono);
  background: var(--bg-3); color: var(--text-dim);
  padding: 4px 10px; border-radius: 20px; border: 1px solid var(--border);
}
.chip.accent { color: var(--accent); border-color: rgba(45,212,191,0.4); }

/* two-col helpers */
.grid-2 { display: grid; grid-template-columns: 1fr; gap: 16px; }
@media (min-width: 760px) { .grid-2 { grid-template-columns: 1fr 1fr; } }
.grid-3 { display: grid; grid-template-columns: 1fr; gap: 16px; }
@media (min-width: 760px) { .grid-3 { grid-template-columns: repeat(3, 1fr); } }

/* note blockquote */
blockquote {
  border-left: 3px solid var(--accent);
  background: var(--bg-2);
  padding: 12px 18px;
  margin: 14px 0;
  border-radius: 0 8px 8px 0;
  color: var(--text-dim);
  font-size: 0.92rem;
}
blockquote strong { color: var(--accent-2); }

/* ==========================================================================
   Footer
   ========================================================================== */
footer {
  border-top: 1px solid var(--border);
  padding: 26px 0 0;
  margin-top: 50px;
  color: var(--text-mute);
  font-size: 0.8rem;
}
footer .f-grid { display: grid; grid-template-columns: 1fr; gap: 10px; }
@media (min-width: 620px) { footer .f-grid { grid-template-columns: 2fr 1fr 1fr; } }
footer a { color: var(--text-dim); text-decoration: none; }
footer p { color: var(--text-mute); }

/* ==========================================================================
   Mobile
   ========================================================================== */
@media (max-width: 880px) {
  .hamburger { display: flex; }
  .nav-links {
    position: fixed;
    top: var(--nav-h); right: 0;
    width: 220px; height: calc(100vh - var(--nav-h));
    background: var(--bg-0);
    border-left: 1px solid var(--border);
    flex-direction: column;
    padding: 16px 12px;
    transform: translateX(110%);
    transition: transform 0.25s ease;
    box-shadow: -8px 0 24px rgba(0,0,0,0.4);
    overflow-y: auto;
  }
  .nav-links.open { transform: translateX(0); }
  .nav-links a { padding: 12px 14px; font-size: 0.92rem; }

  .layout { grid-template-columns: 1fr; }
  .sidebar {
    position: fixed;
    top: var(--nav-h); left: 0;
    width: 240px; height: calc(100vh - var(--nav-h));
    transform: translateX(-110%);
    transition: transform 0.25s ease;
    z-index: 90;
    box-shadow: 8px 0 24px rgba(0,0,0,0.4);
  }
  .sidebar.open { transform: translateX(0); }
  .sidebar-toggle {
    display: flex !important;
  }
  .content { padding: 22px 16px 70px; }

  .heatmaps { grid-template-columns: 1fr; }
  .heatmap { grid-template-columns: 26px repeat(5, 1fr); }
  .heatmap .hcell { font-size: 0.82rem; }

  .chart-canvas-wrap { height: 300px; }
  .chart-canvas-wrap.tall { height: 360px; }

  h2 { font-size: 1.5rem; }
  section { margin-bottom: 40px; }
}

.sidebar-toggle {
  display: none;
  background: none;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--accent);
  width: 40px; height: 40px;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.overlay {
  display: none;
  position: fixed; inset: var(--nav-h) 0 0;
  background: rgba(0,0,0,0.5);
  z-index: 80;
}
.overlay.show { display: block; }

/* back to top */
.totop {
  position: fixed;
  bottom: 22px; right: 22px;
  width: 44px; height: 44px;
  border-radius: 50%;
  background: var(--accent);
  color: var(--bg-0);
  border: none;
  cursor: pointer;
  font-size: 1.2rem;
  font-weight: 700;
  box-shadow: 0 4px 18px var(--accent-glow);
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.25s, transform 0.25s;
  z-index: 70;
}
.totop.show { opacity: 1; transform: translateY(0); }

/* utility */
.muted { color: var(--text-mute); }
.mono { font-family: var(--mono); }
.center { text-align: center; }
.mt-0 { margin-top: 0; }
.hidden { display: none; }

/* KaTeX color tweak for dark theme */
.katex { color: var(--text); }
.katex .mord { color: var(--text); }