:root {
      --ink: #06131f;
      --paper: #ffffff;
      --line: #dbe3ea;
      --muted: #4b5563;
      --signal: #0b63ce;
      --font-sans: HelveticaNeue, "Helvetica Neue", Helvetica, Arial,
        "游ゴシック体", YuGothic, "游ゴシック Medium", "Yu Gothic Medium",
        "游ゴシック", "Yu Gothic", "ヒラギノ角ゴ ProN W3", "Hiragino Kaku Gothic ProN",
        "ヒラギノ角ゴ Pro W3", "Hiragino Kaku Gothic Pro", sans-serif;
      --font-mono: "SF Mono", "Fira Code", "Fira Mono", Menlo, Consolas, monospace;
      font-family: var(--font-sans);
      color: var(--ink);
    }
    * { box-sizing: border-box; }
    body {
      margin: 0;
      font-size: 16px;
      line-height: 1.8;
      font-feature-settings: "palt";
      -webkit-font-smoothing: antialiased;
      background: #f8f7f2;
    }
    a { color: inherit; }
    img { display: block; max-width: 100%; height: auto; }
    .site-header {
      display: flex; align-items: center; justify-content: space-between; gap: 18px;
      min-height: 62px; padding: 14px clamp(20px, 4vw, 58px) 10px;
      box-shadow: inset 0 -1px 0 rgba(6, 19, 31, 0.08);
    }
    .brand { display: inline-flex; align-items: center; gap: 7px; text-decoration: none; }
    .brand-symbol { width: 40px; }
    .brand-wordmark { width: 96px; }
    .back-link {
      font-family: var(--font-mono); font-size: 11px; font-weight: 780;
      letter-spacing: 0.08em; text-decoration: none;
    }
    .back-link:hover, .back-link:focus-visible { color: var(--signal); outline: none; }
    main {
      max-width: 720px; margin: 0 auto;
      padding: clamp(36px, 6vw, 72px) clamp(20px, 4vw, 40px) clamp(60px, 9vw, 110px);
    }
    .section-label {
      margin: 0; color: var(--signal); font-family: var(--font-mono); font-size: 12px;
      font-weight: 780; letter-spacing: 0.1em; text-transform: uppercase;
    }
    h1 { margin: 12px 0 14px; font-size: clamp(26px, 4vw, 36px); font-weight: 820; line-height: 1.25; }
    .lead { margin: 0 0 28px; color: var(--muted); font-size: 15px; }
    .target {
      margin: 0 0 30px; padding: 18px 20px; background: var(--paper);
      border: 1px solid var(--line); border-left: 4px solid var(--signal); border-radius: 10px;
    }
    .target-label {
      margin: 0 0 6px; color: var(--muted); font-family: var(--font-mono);
      font-size: 11px; font-weight: 780; letter-spacing: 0.08em;
    }
    .target-page { margin: 0 0 6px; font-size: 14px; font-weight: 700; }
    .target-page a { text-underline-offset: 3px; }
    .target-q { margin: 0; font-size: 16.5px; font-weight: 800; line-height: 1.6; }
    .target-q .num { display: inline-block; margin-right: 8px; color: var(--signal); font-size: 13px; }
    .target-change { margin: 10px 0 0; font-size: 12.5px; color: var(--muted); }
    form { display: grid; gap: 24px; }
    fieldset { margin: 0; padding: 0; border: 0; }
    legend, label.field-label {
      display: block; margin: 0 0 8px; font-size: 15px; font-weight: 800;
    }
    .optional { margin-left: 6px; color: var(--muted); font-size: 12px; font-weight: 600; }
    .kinds { display: flex; flex-wrap: wrap; gap: 8px; }
    .kinds label {
      display: inline-flex; align-items: center; gap: 6px; padding: 7px 14px;
      background: var(--paper); border: 1px solid var(--line); border-radius: 999px;
      font-size: 14px; cursor: pointer;
    }
    .kinds input { accent-color: var(--signal); }
    .kinds label:has(input:checked) { border-color: var(--signal); background: rgba(11, 99, 206, 0.07); }
    textarea, input[type="text"], input[type="email"] {
      width: 100%; padding: 12px 14px; font: inherit; font-size: 15px; color: var(--ink);
      background: var(--paper); border: 1px solid #c8d2dc; border-radius: 8px;
    }
    textarea { min-height: 180px; resize: vertical; line-height: 1.7; }
    textarea:focus, input:focus { outline: 2px solid rgba(11, 99, 206, 0.35); border-color: var(--signal); }
    .hint { margin: 6px 0 0; color: var(--muted); font-size: 12.5px; }
    .row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
    @media (max-width: 560px) { .row { grid-template-columns: 1fr; } }
    .note {
      margin: 0; padding: 14px 16px; background: rgba(6, 19, 31, 0.04); border-radius: 8px;
      color: var(--muted); font-size: 13px; line-height: 1.75;
    }
    button[type="submit"] {
      justify-self: start; padding: 12px 28px; font: inherit; font-size: 15px; font-weight: 800;
      color: #fff; background: var(--ink); border: 0; border-radius: 999px; cursor: pointer;
    }
    button[type="submit"]:hover, button[type="submit"]:focus-visible { background: var(--signal); outline: none; }
    .hp { position: absolute; left: -10000px; width: 1px; height: 1px; overflow: hidden; }
    .form-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 18px; }
    .form-status { margin: 0; font-size: 13.5px; color: var(--muted); }
    .form-status.is-error { color: #b42318; }
    button[type="submit"]:disabled { opacity: 0.55; cursor: wait; }
    html[data-color-mode="dark"] button[type="submit"] { color: #07121c; background: #edf4fa; }
    html[data-color-mode="dark"] button[type="submit"]:hover,
    html[data-color-mode="dark"] button[type="submit"]:focus-visible { color: #07121c; background: #7cbcff; }
    html[data-color-mode="dark"] .target { background: #0d1b28; border-color: #2b4154; border-left-color: #7cbcff; }
    html[data-color-mode="dark"] .kinds label { background: #0d1b28; border-color: #2b4154; }
    html[data-color-mode="dark"] .kinds label:has(input:checked) { border-color: #7cbcff; background: rgba(124, 188, 255, 0.16); }
    html[data-color-mode="dark"] .note { background: rgba(237, 244, 250, 0.06); }
    html[data-color-mode="dark"] .form-status.is-error { color: #ff8a80; }
    html[data-color-mode="dark"] .result { background: #0d1b28; border-color: #2b4154; }
    .preview-banner {
      margin: 0 0 24px; padding: 10px 14px; border: 1px dashed #b45309; border-radius: 8px;
      color: #92400e; background: #fffbeb; font-size: 13px; font-weight: 700;
    }
    .result { display: none; padding: 20px; background: var(--paper); border: 1px solid var(--line); border-radius: 10px; }
    .result h2 { margin: 0 0 8px; font-size: 18px; }
    .result p { margin: 0 0 8px; }
    .result pre {
      margin: 12px 0 0; padding: 14px; overflow-x: auto; white-space: pre-wrap;
      background: #0f1720; color: #e5edf5; border-radius: 8px; font-size: 12.5px; line-height: 1.6;
    }
    .site-footer {
      display: flex; flex-wrap: wrap; justify-content: space-between; gap: 10px 16px;
      padding: 18px clamp(20px, 4vw, 58px); color: var(--muted); font-family: var(--font-mono);
      font-size: 11px; font-weight: 850; box-shadow: inset 0 1px 0 rgba(6, 19, 31, 0.08);
    }
    .site-footer a { text-decoration: none; }