:root {
  --bg:        #0d1411;
  --bg-soft:   #121d18;
  --card:      #16241d;
  --card-2:    #1b2c23;
  --line:      #25382d;
  --text:      #e7efe9;
  --muted:     #9db3a6;
  --green:     #3ddc84;
  --green-deep:#1f9d5b;
  --sun:       #ffce4a;
  --sun-deep:  #f5a623;
  --blue:      #5db0ff;
  --radius:    16px;
  --maxw:      1080px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--green); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3 { line-height: 1.2; letter-spacing: -0.02em; }
img { max-width: 100%; display: block; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 22px; }

/* ── Nav ───────────────────────────────────────────── */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(13,20,17,0.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav .wrap { display: flex; align-items: center; gap: 18px; height: 60px; }
.nav .brand { font-weight: 700; margin-right: auto; display: flex; align-items: center; gap: 9px; }
.nav .brand .dot { width: 11px; height: 11px; border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, var(--sun), var(--sun-deep)); box-shadow: 0 0 14px var(--sun-deep); }
.nav a.link { color: var(--muted); font-size: 0.92rem; }
.nav a.link:hover { color: var(--text); text-decoration: none; }
@media (max-width: 760px) { .nav a.link { display: none; } }

/* ── Hero ──────────────────────────────────────────── */
.hero {
  position: relative;
  padding: 84px 0 64px;
  background:
    radial-gradient(900px 400px at 80% -10%, rgba(255,206,74,0.14), transparent 60%),
    radial-gradient(700px 500px at 10% 10%, rgba(61,220,132,0.10), transparent 60%),
    var(--bg);
  border-bottom: 1px solid var(--line);
}
.hero .eyebrow { color: var(--sun); font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; font-size: 0.8rem; }
.hero h1 { font-size: clamp(2.1rem, 5vw, 3.4rem); margin: 12px 0 14px; }
.hero h1 .accent { color: var(--green); }
.hero p.lead { font-size: 1.15rem; color: var(--muted); max-width: 640px; }
.hero .pills { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 26px; }
.pill { background: var(--card); border: 1px solid var(--line); border-radius: 999px; padding: 7px 15px; font-size: 0.88rem; color: var(--text); }
.pill b { color: var(--green); }

/* ── Sections ──────────────────────────────────────── */
section { padding: 64px 0; border-bottom: 1px solid var(--line); }
section h2 { font-size: clamp(1.5rem, 3vw, 2rem); margin: 0 0 6px; }
section .sub { color: var(--muted); margin: 0 0 32px; max-width: 680px; }
.kicker { color: var(--sun); font-weight: 600; text-transform: uppercase; letter-spacing: 0.08em; font-size: 0.78rem; }

/* ── Stat cards ────────────────────────────────────── */
.stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: 14px; }
.stat { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; }
.stat .n { font-size: 1.9rem; font-weight: 700; color: var(--green); line-height: 1; }
.stat .n.sun { color: var(--sun); }
.stat .l { color: var(--muted); font-size: 0.86rem; margin-top: 8px; }

/* ── Generic cards / grid ──────────────────────────── */
.grid { display: grid; gap: 16px; }
.grid.two { grid-template-columns: 1fr 1fr; }
.grid.three { grid-template-columns: repeat(3, 1fr); }
@media (max-width: 760px) { .grid.two, .grid.three { grid-template-columns: 1fr; } }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 22px; }
.card h3 { margin: 0 0 8px; font-size: 1.08rem; }
.card h3 .ic { margin-right: 8px; }
.card p { margin: 0; color: var(--muted); font-size: 0.95rem; }

/* ── Flow diagram ──────────────────────────────────── */
.flow { display: flex; flex-wrap: wrap; align-items: stretch; gap: 12px; }
.flow .node {
  flex: 1 1 150px; background: var(--card); border: 1px solid var(--line);
  border-radius: 14px; padding: 16px; text-align: center; min-width: 140px;
}
.flow .node .big { font-size: 1.6rem; }
.flow .node .t { font-weight: 700; margin-top: 6px; font-size: 0.98rem; }
.flow .node .d { color: var(--muted); font-size: 0.82rem; margin-top: 4px; }
.flow .node.sun  { border-color: rgba(255,206,74,0.4); }
.flow .node.batt { border-color: rgba(61,220,132,0.4); }
.flow .node.grid { border-color: rgba(93,176,255,0.4); }
.flow .arrow { align-self: center; color: var(--muted); font-size: 1.4rem; }
@media (max-width: 760px) { .flow { flex-direction: column; } .flow .arrow { transform: rotate(90deg); } }

/* ── Flow hub (Grid above / House below the Victron, two-way battery) ── */
.flow-hub {
  display: grid; gap: 10px; align-items: center; justify-items: stretch;
  grid-template-columns: 1fr auto 1fr auto 1.25fr auto 1fr;
  grid-template-areas:
    ".   .  .     .  grid    .  ."
    ".   .  .     .  gc      .  ."
    "pv  a1 solis a2 victron a3 batt"
    ".   .  .     .  hc      .  ."
    ".   .  .     .  house   .  .";
}
.flow-hub .node {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px;
  padding: 14px 12px; text-align: center;
}
.flow-hub .node .big { font-size: 1.5rem; }
.flow-hub .node .t { font-weight: 700; margin-top: 6px; font-size: 0.95rem; }
.flow-hub .node .d { color: var(--muted); font-size: 0.8rem; margin-top: 3px; }
.flow-hub .conn { color: var(--muted); font-size: 1.5rem; text-align: center; }
.flow-hub .node.sun     { border-color: rgba(255,206,74,.45); }
.flow-hub .node.batt    { border-color: rgba(61,220,132,.45); }
.flow-hub .node.grid    { border-color: rgba(93,176,255,.45); }
.flow-hub .node.house   { border-color: rgba(224,121,91,.50); }
.flow-hub .node.victron { border-color: rgba(61,220,132,.65); background: var(--card-2); }
@media (max-width: 760px) {
  .flow-hub {
    grid-template-columns: 1fr;
    grid-template-areas: "grid" "gc" "pv" "a1" "solis" "a2" "victron" "a3" "batt" "hc" "house";
  }
}

/* ── Day timeline ──────────────────────────────────── */
.timeline { display: grid; grid-template-columns: repeat(5, 1fr); gap: 12px; }
@media (max-width: 760px) { .timeline { grid-template-columns: 1fr; } }
.tstep { background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 16px; }
.tstep .when { font-size: 1.4rem; }
.tstep .ttl { font-weight: 700; margin: 6px 0 4px; font-size: 0.95rem; }
.tstep p { margin: 0; color: var(--muted); font-size: 0.85rem; }

/* ── Tables ────────────────────────────────────────── */
.tablewrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); }
table { width: 100%; border-collapse: collapse; font-size: 0.92rem; }
th, td { text-align: left; padding: 11px 14px; border-bottom: 1px solid var(--line); }
thead th { background: var(--card-2); color: var(--text); font-weight: 600; }
tbody tr:last-child td { border-bottom: none; }
td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }
.peak { color: var(--sun-deep); font-weight: 600; }
.off  { color: var(--green); font-weight: 600; }

/* ── Figure ────────────────────────────────────────── */
figure { margin: 0; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px; }
figure img { border-radius: 10px; }
figcaption { color: var(--muted); font-size: 0.85rem; margin-top: 10px; }

/* ── Callout ───────────────────────────────────────── */
.callout { background: linear-gradient(120deg, rgba(61,220,132,0.08), rgba(255,206,74,0.06));
  border: 1px solid var(--line); border-left: 3px solid var(--green); border-radius: 12px; padding: 18px 20px; }
.callout.sun { border-left-color: var(--sun); }
.callout b { color: var(--text); }

/* ── Docs / downloads ──────────────────────────────── */
.docs { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; }
.doc { display: flex; gap: 12px; align-items: center; background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 14px 16px; }
.doc:hover { border-color: var(--green-deep); text-decoration: none; }
.doc .ic { font-size: 1.5rem; flex: none; }
.doc img.ic { width: 34px; height: 34px; object-fit: contain; background: #fff; border-radius: 7px; padding: 3px; }
.doc .t { font-weight: 600; color: var(--text); font-size: 0.95rem; }
.doc .m { color: var(--muted); font-size: 0.8rem; }

/* ── Badges ────────────────────────────────────────── */
.badge { display: inline-block; font-size: 0.72rem; padding: 2px 8px; border-radius: 999px; border: 1px solid var(--line); color: var(--muted); vertical-align: middle; }
.badge.ok { color: var(--green); border-color: var(--green-deep); }
.badge.todo { color: var(--sun); border-color: var(--sun-deep); }

/* ── Button ────────────────────────────────────────── */
.btn {
  font: inherit; font-weight: 600; cursor: pointer;
  color: #0d1411; background: linear-gradient(120deg, var(--green), var(--green-deep));
  border: none; border-radius: 999px; padding: 11px 22px; font-size: 0.98rem;
  transition: transform .08s ease, filter .15s ease;
}
.btn:hover { filter: brightness(1.08); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: .6; cursor: progress; filter: none; }

/* ── Charts (Chart.js canvases need a sized box) ───── */
.chart { width: 100%; height: auto; display: block; }
#chart-pv, #chart-grid, #chart-roi, #chart-forecast, #chart-week, #chart-combined { position: relative; height: 250px; }
#chart-combined { height: 300px; }
@media (max-width: 760px) { #chart-pv, #chart-grid, #chart-roi, #chart-forecast, #chart-week, #chart-combined { height: 210px; } }

/* ── ROI view toggle ───────────────────────────────── */
.roi-toggle { display: inline-flex; gap: 4px; background: var(--card); border: 1px solid var(--line); border-radius: 999px; padding: 3px; }
.btn-toggle {
  font: inherit; font-size: 0.8rem; cursor: pointer; color: var(--muted);
  background: transparent; border: none; border-radius: 999px; padding: 5px 12px;
}
.btn-toggle.active { background: var(--green-deep); color: #0d1411; font-weight: 600; }

/* ── Week navigation ───────────────────────────────── */
.weeknav { display: flex; align-items: center; gap: 14px; }
.weeklabel { font-weight: 700; font-size: 1.05rem; min-width: 12em; text-align: center; }
.btn-arrow {
  font: inherit; cursor: pointer; color: var(--text);
  background: var(--card); border: 1px solid var(--line); border-radius: 10px;
  width: 40px; height: 40px; font-size: 1.1rem; line-height: 1;
  transition: border-color .15s ease, opacity .15s ease;
}
.btn-arrow:hover:not(:disabled) { border-color: var(--green-deep); }
.btn-arrow:disabled { opacity: .35; cursor: default; }

/* ── ROI progress bar ──────────────────────────────── */
.roi-bar {
  position: relative; height: 30px; border-radius: 999px;
  background: var(--card-2); border: 1px solid var(--line); overflow: hidden;
}
.roi-fill {
  height: 100%; width: 0;
  background: linear-gradient(90deg, var(--green-deep), var(--green), var(--sun));
  border-radius: 999px; transition: width 1.4s cubic-bezier(.22,.61,.36,1);
}
.roi-label {
  position: absolute; inset: 0; display: flex; align-items: center; justify-content: center;
  font-size: 0.82rem; font-weight: 600; color: var(--text);
  text-shadow: 0 1px 2px rgba(0,0,0,.5);
}

/* ── Footer ────────────────────────────────────────── */
footer { padding: 40px 0 60px; color: var(--muted); font-size: 0.88rem; }
footer .wrap { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }

.muted { color: var(--muted); }
.small { font-size: 0.82rem; }

/* ── Hero brand (slim banner) ──────────────────────── */
.hero .brand { display: inline-flex; align-items: center; gap: 9px; font-weight: 700; color: var(--text); margin-bottom: 14px; }
.hero .brand .dot { width: 11px; height: 11px; border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, var(--sun), var(--sun-deep)); box-shadow: 0 0 14px var(--sun-deep); }
.hero { padding: 48px 0 40px; }

/* ── Tab bar ───────────────────────────────────────── */
.tabs {
  position: sticky; top: 0; z-index: 50;
  background: rgba(13,20,17,0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.tabs .wrap { display: flex; gap: 6px; overflow-x: auto; padding-top: 9px; padding-bottom: 9px; scrollbar-width: thin; }
.tab-btn {
  flex: 0 0 auto; font: inherit; font-size: 0.92rem; font-weight: 600; cursor: pointer;
  color: var(--muted); background: transparent; border: 1px solid transparent;
  border-radius: 999px; padding: 8px 16px; white-space: nowrap;
  transition: color .15s ease, background .15s ease;
}
.tab-btn:hover { color: var(--text); }
.tab-btn.active { color: #0d1411; background: linear-gradient(120deg, var(--green), var(--green-deep)); }

/* ── Tab panels ────────────────────────────────────── */
.tabpanel { display: none; padding: 48px 0; border-bottom: 1px solid var(--line); }
.tabpanel.active { display: block; animation: tabfade .28s ease; }
@keyframes tabfade { from { opacity: 0; transform: translateY(5px); } to { opacity: 1; transform: none; } }
.tabpanel h3 { font-size: 1.2rem; }