/* ============================================================
   /css/tool.css — shared chrome for btclyzer tool pages.

   Loaded via <link rel="stylesheet" href="/css/tool.css?v=1">
   alongside /css/topbar.css. Each tool keeps a small inline
   <style> block ONLY for its own component classes (charts,
   heatmaps, KPI grids, AI-summary variants, etc.).

   Everything in this file is identical across the visualisation
   tools (halving-cycle analyzer, Fear & Greed history, mempool
   fee heatmap) — extracted to stop copy-pasting ~120 lines of
   chrome into every new tool.
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;600&family=Space+Grotesk:wght@300;400;500;600;700&display=optional');

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

:root{
  --bg:#0b0d11; --bg2:#111318; --bg3:#181b22; --bg4:#1e2129;
  --border:rgba(255,255,255,0.07); --border2:rgba(255,255,255,0.13);
  --text:#e8eaf0; --text2:#9aa0ad; --text3:#6b7280;
  --green:#22c55e; --red:#ef4444; --amber:#f59e0b; --blue:#3b82f6; --purple:#a855f7;
  --acc:#f7931a; --acc2:#ff6b35;
  --accdim:rgba(247,147,26,0.10); --accb:rgba(247,147,26,0.35);
  --gdim:rgba(34,197,94,0.12); --gb:rgba(34,197,94,0.35);
  --rdim:rgba(239,68,68,0.12); --rb:rgba(239,68,68,0.35);
  --mono:'JetBrains Mono',ui-monospace,monospace;
  --sans:'Space Grotesk',system-ui,-apple-system,sans-serif;
}
html,body{background:var(--bg);color:var(--text);font-family:var(--sans);font-size:16px;line-height:1.6;-webkit-font-smoothing:antialiased}
a{color:var(--acc);text-decoration:none}
a:hover{color:var(--acc2)}
img,svg{display:block;max-width:100%}

.container{max-width:1180px;margin:0 auto;padding:0 24px}

/* Topbar */
.topbar{position:sticky;top:0;z-index:50;background:rgba(11,13,17,0.85);backdrop-filter:saturate(140%) blur(12px);-webkit-backdrop-filter:saturate(140%) blur(12px);border-bottom:1px solid var(--border)}
.topbar-inner{display:flex;align-items:center;justify-content:space-between;height:64px;max-width:1180px;margin:0 auto;padding:0 24px}
.brand{display:flex;align-items:center;gap:10px}
.brand a{color:inherit}
.brand-mark{width:32px;height:32px;border-radius:8px;background:linear-gradient(135deg,var(--acc),var(--acc2));display:flex;align-items:center;justify-content:center;font-family:var(--mono);font-weight:800;color:#fff;font-size:16px;box-shadow:0 4px 14px rgba(247,147,26,0.35)}
.brand-name{font-size:16px;font-weight:600;letter-spacing:-.01em}
.nav{display:flex;align-items:center;gap:8px}
.nav-link{font-size:14px;color:var(--text2);padding:8px 12px;border-radius:8px;transition:color .15s,background .15s}
.nav-link:hover{color:var(--text);background:var(--bg3)}
.nav-link.active{color:var(--acc)}
.btn{display:inline-flex;align-items:center;gap:6px;font-family:var(--sans);font-weight:600;font-size:14px;padding:10px 18px;border-radius:10px;border:1px solid transparent;cursor:pointer;transition:transform .15s,box-shadow .15s;white-space:nowrap;color:#fff}
.btn:hover{transform:translateY(-1px)}
.btn-primary{background:linear-gradient(135deg,var(--acc),var(--acc2));color:#fff;box-shadow:0 4px 14px rgba(247,147,26,0.35)}
.btn-primary:hover{box-shadow:0 6px 24px rgba(247,147,26,0.5)}
.btn-lg{padding:14px 22px;font-size:15px}

/* Breadcrumb / hero */
.breadcrumb{font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--text3);margin-bottom:18px}
.breadcrumb a{color:var(--text3)}
.breadcrumb a:hover{color:var(--text2)}
.breadcrumb .sep{margin:0 8px}
.hero{padding:80px 0 24px}
.eyebrow{display:inline-flex;align-items:center;gap:8px;font-family:var(--mono);font-size:11px;letter-spacing:.16em;color:var(--acc);text-transform:uppercase;font-weight:600;padding:6px 12px;border-radius:99px;background:var(--accdim);border:1px solid var(--accb)}
h1{font-size:clamp(32px,4vw,46px);font-weight:600;letter-spacing:-.025em;line-height:1.1;margin:18px 0 14px}
.hero-sub{font-size:17px;color:var(--text2);max-width:680px}

/* Tool body wrapper */
.calc{padding:24px 0 56px}

/* Loading / spinner */
.loading{text-align:center;padding:70px 24px;color:var(--text3);font-family:var(--mono);font-size:13px}
.loading-spin{display:inline-block;width:24px;height:24px;border:2px solid var(--border2);border-top-color:var(--acc);border-radius:50%;animation:spin 1s linear infinite;margin-bottom:12px}
@keyframes spin{to{transform:rotate(360deg)}}

/* Explainer / FAQ / CTA / footer */
.explain{padding:48px 0;background:linear-gradient(180deg,transparent,rgba(255,255,255,.015),transparent)}
.explain h2{font-size:28px;font-weight:600;letter-spacing:-.015em;margin:32px 0 12px}
.explain h2:first-child{margin-top:0}
.explain h3{font-size:18px;font-weight:600;margin:22px 0 10px}
.explain p{margin:0 0 14px;color:var(--text);font-size:16px;line-height:1.65}
.explain ul{margin:0 0 18px;padding-left:22px;color:var(--text)}
.explain li{margin-bottom:6px}
.explain strong{color:var(--text)}
.faq{padding:32px 0 56px}
.faq h2{font-size:24px;font-weight:600;margin-bottom:18px}
details{background:var(--bg2);border:1px solid var(--border);border-radius:12px;margin-bottom:10px;overflow:hidden}
summary{cursor:pointer;list-style:none;padding:16px 20px;font-size:15px;font-weight:500;display:flex;justify-content:space-between;align-items:center;color:var(--text)}
summary::-webkit-details-marker{display:none}
summary::after{content:"+";font-family:var(--mono);font-size:18px;color:var(--text3);transition:transform .2s}
details[open] summary::after{transform:rotate(45deg);color:var(--acc)}
details .answer{padding:0 20px 16px;color:var(--text2);font-size:14px;line-height:1.7}
.cta{padding:24px 0 48px}
.cta-card{background:linear-gradient(135deg,rgba(247,147,26,0.10),rgba(255,107,53,0.05));border:1px solid var(--accb);border-radius:16px;padding:36px;text-align:center}
.cta-card h2{font-size:24px;font-weight:600;margin-bottom:10px}
.cta-card p{color:var(--text2);margin-bottom:20px;font-size:15px;max-width:560px;margin-left:auto;margin-right:auto}
footer{border-top:1px solid var(--border);padding:32px 0 56px;color:var(--text3);font-size:13px}
.foot-grid{max-width:1180px;margin:0 auto;padding:0 24px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:24px;align-items:center}
.foot-links{display:flex;gap:24px;flex-wrap:wrap}
.foot-links a{color:var(--text3)}
.foot-links a:hover{color:var(--text)}
.foot-disclaimer{max-width:680px;margin:20px auto 0;padding:0 24px;font-size:12px;color:var(--text3);line-height:1.6;text-align:center}

/* Shared responsive chrome */
@media(max-width:700px){
  .container{padding:0 18px}
  .topbar-inner{height:56px;padding:0 18px}
  .hero{padding:36px 0 16px}
  .hero-sub{font-size:15px}
  .explain h2{font-size:22px}
  .explain p{font-size:15px}
  .cta-card{padding:28px 20px}
  .cta-card h2{font-size:20px}
  .foot-grid{flex-direction:column;align-items:flex-start;padding:0 18px}
}
@media(max-width:420px){
  .topbar-inner{height:52px}
  .brand-mark{width:28px;height:28px;font-size:14px}
  .brand-name{font-size:14px}
  .nav .btn{padding:7px 11px;font-size:12px}
}