/* GPTChart.site — shared styles */
:root{
  --bg:#f6f7fb; --card:#fff; --ink:#111827; --muted:#6b7280; --line:#e5e7eb;
  --brand:#4f46e5; --brand-dark:#4338ca; --brand-soft:#e0e7ff; --accent:#06b6d4;
  --radius:14px; --shadow:0 1px 2px rgba(17,24,39,.05),0 10px 30px rgba(17,24,39,.07);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;color:var(--ink);background:var(--bg);line-height:1.65}
a{color:var(--brand-dark)}
.container{max-width:1080px;margin:0 auto;padding:0 20px}
.site-header{background:#fff;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:50}
.site-header .inner{display:flex;align-items:center;justify-content:space-between;height:60px}
.logo{font-weight:800;font-size:20px;color:var(--ink);text-decoration:none;display:flex;align-items:center;gap:8px}
.logo .dot{width:26px;height:26px;border-radius:8px;background:linear-gradient(135deg,var(--brand),var(--accent));display:inline-flex;align-items:center;justify-content:center;color:#fff;font-size:13px;font-weight:900}
.nav{display:flex;gap:4px;flex-wrap:wrap}
.nav a{padding:8px 11px;border-radius:8px;text-decoration:none;color:var(--muted);font-size:14px;font-weight:500}
.nav a:hover{background:var(--brand-soft);color:var(--brand-dark)}
.hero{padding:34px 0 8px}
.hero h1{font-size:clamp(26px,4vw,38px);line-height:1.2;margin:0 0 10px}
.hero .sub{color:var(--muted);font-size:17px;max-width:660px;margin:0 0 6px}
.badge{display:inline-block;background:var(--brand-soft);color:var(--brand-dark);border-radius:999px;padding:2px 10px;font-size:12.5px;font-weight:700;margin-bottom:10px}
.tool-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:22px;margin:22px 0}
.tool-grid{display:grid;grid-template-columns:1fr 1fr;gap:18px}
@media(max-width:860px){.tool-grid{grid-template-columns:1fr}}
textarea{width:100%;min-height:170px;padding:12px;border:1px solid var(--line);border-radius:10px;font:13.5px/1.6 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;resize:vertical;background:#fbfbfe;color:var(--ink)}
textarea:focus{outline:2px solid var(--brand-soft);border-color:var(--brand)}
.field{margin-bottom:12px}
.field label{display:block;font-size:13px;color:var(--muted);margin-bottom:4px;font-weight:600}
.field input[type=text],.field select{width:100%;padding:8px 10px;border:1px solid var(--line);border-radius:8px;font-size:14px;background:#fff;color:var(--ink)}
.chart-wrap{background:#fff;border:1px solid var(--line);border-radius:12px;min-height:300px;display:flex;align-items:center;justify-content:center;overflow:hidden}
.chart-wrap canvas{max-width:100%;height:auto;display:block}
.type-tabs{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:12px}
.type-tabs button{padding:7px 14px;border-radius:8px;border:1px solid var(--line);background:#fff;cursor:pointer;font-size:13.5px;font-weight:600;color:var(--muted)}
.type-tabs button.on{background:var(--brand);border-color:var(--brand);color:#fff}
.samples{display:flex;gap:8px;flex-wrap:wrap;margin-top:10px}
.samples button{padding:5px 10px;border-radius:8px;border:1px dashed var(--line);background:#fbfbfe;font-size:12.5px;color:var(--muted);cursor:pointer}
.samples button:hover{border-color:var(--brand);color:var(--brand-dark)}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;padding:11px 20px;border-radius:10px;border:0;background:var(--brand);color:#fff;font-size:15px;font-weight:700;cursor:pointer;text-decoration:none}
.btn:hover{background:var(--brand-dark)}
.btn.ghost{background:#fff;color:var(--ink);border:1px solid var(--line)}
.btn.small{padding:7px 12px;font-size:13px}
.parse-note{font-size:13px;color:var(--muted);margin-top:8px}
.data-table{width:100%;border-collapse:collapse;font-size:13.5px;margin-top:10px}
.data-table th{ text-align:left;color:var(--muted);font-size:12px;border-bottom:1px solid var(--line);padding:4px 6px}
.data-table td{border-bottom:1px solid #f1f2f6;padding:3px 6px}
.data-table input{width:100%;border:0;background:transparent;font:inherit;color:inherit;padding:3px 4px}
.data-table input:focus{outline:1.5px solid var(--brand-soft);background:#fff;border-radius:4px}
section.content{padding:24px 0}
section.content h2{font-size:24px;margin:32px 0 12px}
section.content h3{font-size:18px;margin:20px 0 8px}
section.content p,section.content li{color:#374151;max-width:760px}
.features{display:grid;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));gap:14px;margin:18px 0}
.features .f{background:#fff;border:1px solid var(--line);border-radius:12px;padding:16px}
.features .f b{display:block;margin-bottom:4px}
.features .f span{font-size:14px;color:var(--muted)}
.steps{counter-reset:step;list-style:none;padding:0;margin:16px 0}
.steps li{counter-increment:step;position:relative;padding:0 0 14px 44px;color:#374151;max-width:720px}
.steps li:before{content:counter(step);position:absolute;left:0;top:0;width:30px;height:30px;border-radius:50%;background:var(--brand-soft);color:var(--brand-dark);font-weight:700;display:flex;align-items:center;justify-content:center;font-size:14px}
.faq details{background:#fff;border:1px solid var(--line);border-radius:10px;padding:14px 16px;margin-bottom:10px}
.faq summary{font-weight:700;cursor:pointer}
.faq p{margin:10px 0 0}
.gallery{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:14px;margin:16px 0}
.gallery figure{margin:0;background:#fff;border:1px solid var(--line);border-radius:12px;padding:12px}
.gallery canvas{width:100%;height:auto;border-radius:8px}
.gallery figcaption{font-size:13px;color:var(--muted);margin-top:6px;text-align:center}
.related{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:12px;margin:16px 0}
.related a{display:block;background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px;text-decoration:none;color:var(--ink)}
.related a:hover{border-color:var(--brand);box-shadow:var(--shadow)}
.related b{display:block;margin-bottom:4px;font-size:14.5px}
.related span{font-size:13px;color:var(--muted)}
.crumbs{font-size:13.5px;color:var(--muted);padding:16px 0 0}
.crumbs a{color:var(--muted)}
.site-footer{background:#111827;color:#9ca3af;margin-top:48px;padding:34px 0;font-size:14px}
.site-footer a{color:#d1d5db}
.site-footer .cols{display:flex;justify-content:space-between;gap:24px;flex-wrap:wrap}
.site-footer ul{list-style:none;padding:0;margin:8px 0 0}
.site-footer li{margin:4px 0}
.note{font-size:13px;color:var(--muted)}