:root {
  --ink: #1f2430;
  --ink-soft: #5b6472;
  --paper: #faf7f2;
  --panel: #ffffff;
  --line: #e6e0d6;
  --accent: #c2410c;
  --accent-soft: #fff1e7;
  --pro: #7c3aed;
  --pro-soft: #f3eefe;
  --ok: #15803d;
  --radius: 12px;
  --shadow: 0 1px 2px rgb(31 36 48 / 0.06), 0 8px 24px rgb(31 36 48 / 0.07);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.55;
}

.wrap-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  background: var(--panel);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 10;
}
.site-header .wrap-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}
.logo { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 1.1rem; }
.logo-mark { color: var(--accent); font-size: 1.5rem; line-height: 1; }
.header-nav { display: flex; align-items: center; gap: 12px; }
.header-nav a { color: var(--ink-soft); text-decoration: none; font-size: 0.92rem; }
.header-nav a:hover { color: var(--ink); }

/* Buttons */
.btn {
  font: inherit;
  font-size: 0.92rem;
  font-weight: 600;
  padding: 9px 16px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
  text-decoration: none;
  display: inline-block;
  text-align: center;
  transition: transform 0.06s ease, box-shadow 0.12s ease;
}
.btn:hover { box-shadow: var(--shadow); }
.btn:active { transform: translateY(1px); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-pro { background: var(--pro); border-color: var(--pro); color: #fff; }
.btn-ghost { border-color: transparent; background: transparent; color: var(--ink-soft); }
.btn[disabled] { opacity: 0.55; cursor: not-allowed; }
.linklike {
  font: inherit; background: none; border: none; color: var(--accent);
  text-decoration: underline; cursor: pointer; padding: 0;
}

/* Hero */
.hero { padding: 44px 0 10px; max-width: 720px; }
.hero h1 { font-size: 2rem; line-height: 1.2; margin: 0 0 12px; }
.hero p { color: var(--ink-soft); font-size: 1.05rem; margin: 0; }

/* Studio layout */
.studio {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 20px;
  margin: 28px 0 12px;
}
@media (max-width: 800px) { .studio { grid-template-columns: 1fr; } }

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
}

/* Controls */
.mode-tabs { display: flex; gap: 6px; margin-bottom: 14px; }
.tab {
  flex: 1; font: inherit; font-size: 0.88rem; font-weight: 600;
  padding: 8px 10px; border-radius: 8px; border: 1px solid var(--line);
  background: var(--paper); color: var(--ink-soft); cursor: pointer;
}
.tab.active { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }
.pro-chip {
  font-size: 0.62rem; font-weight: 800; letter-spacing: 0.04em;
  background: var(--pro-soft); color: var(--pro);
  border-radius: 4px; padding: 1px 4px; vertical-align: 2px;
}

label { display: block; font-size: 0.82rem; font-weight: 600; color: var(--ink-soft); margin: 12px 0 4px; }
select, input[type="number"], input[type="text"] {
  width: 100%; font: inherit; padding: 9px 10px;
  border: 1px solid var(--line); border-radius: 8px; background: #fff; color: var(--ink);
}
select:focus, input:focus { outline: 2px solid var(--accent); outline-offset: 1px; border-color: var(--accent); }

.field-row { display: flex; gap: 10px; }
.field { flex: 1; }
.dims-note { font-size: 0.8rem; color: var(--ink-soft); margin: 8px 0 0; }

.options { margin-top: 16px; border-top: 1px solid var(--line); padding-top: 8px; }
.options summary { font-size: 0.88rem; font-weight: 700; cursor: pointer; color: var(--ink); padding: 6px 0; }
.check { display: flex; align-items: center; gap: 8px; font-weight: 500; margin: 8px 0 0; font-size: 0.88rem; }
.check input { accent-color: var(--accent); }

.export-buttons { display: flex; flex-direction: column; gap: 8px; margin-top: 18px; }
.status { min-height: 1.2em; font-size: 0.82rem; color: var(--ok); margin: 10px 0 0; }
.status.err { color: #b91c1c; }

/* Preview */
.preview { display: flex; flex-direction: column; align-items: center; justify-content: center; min-height: 380px; }
#preview-canvas {
  max-width: 100%;
  background:
    linear-gradient(45deg, #f0ece4 25%, transparent 25%, transparent 75%, #f0ece4 75%),
    linear-gradient(45deg, #f0ece4 25%, transparent 25%, transparent 75%, #f0ece4 75%);
  background-size: 20px 20px;
  background-position: 0 0, 10px 10px;
  border-radius: 8px;
}
.readout { margin-top: 12px; font-size: 0.9rem; color: var(--ink-soft); text-align: center; }
.readout strong { color: var(--ink); }

/* Explainer + FAQ */
.explainer { margin: 48px 0; }
.explainer h2, .faq h2 { font-size: 1.4rem; margin: 0 0 16px; }
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
@media (max-width: 800px) { .cards { grid-template-columns: 1fr; } }
.card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 18px;
}
.card h3 { margin: 0 0 8px; font-size: 1rem; }
.card p { margin: 0; font-size: 0.9rem; color: var(--ink-soft); }

.faq { margin: 48px 0 64px; max-width: 720px; }
.faq details {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: 10px; padding: 12px 16px; margin-bottom: 10px;
}
.faq summary { font-weight: 600; cursor: pointer; }
.faq p { color: var(--ink-soft); font-size: 0.92rem; }

/* Footer */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 20px 0;
  color: var(--ink-soft);
  font-size: 0.85rem;
  background: var(--panel);
}

/* Modals */
dialog {
  border: none; border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 26px; max-width: 420px; width: calc(100vw - 40px);
}
dialog::backdrop { background: rgb(31 36 48 / 0.45); }
dialog h2 { margin: 0 0 10px; font-size: 1.25rem; }
dialog ul { padding-left: 20px; color: var(--ink-soft); font-size: 0.92rem; }
dialog li { margin-bottom: 6px; }
.price { color: var(--ink-soft); }
.price strong { color: var(--ink); font-size: 1.3rem; }
.modal-actions { display: flex; gap: 10px; margin-top: 18px; }
.fine { font-size: 0.82rem; color: var(--ink-soft); margin-top: 14px; }
.error { color: #b91c1c; font-size: 0.85rem; min-height: 1.2em; margin: 8px 0 0; }