/* ==========================================================================
   建設業 規制監視サービス（仮称）検証LP スタイルシート
   依存ゼロ・システムフォントのみ。CDN/外部フォント読み込みなし。
   ========================================================================== */

:root {
  --color-bg: #ffffff;
  --color-bg-alt: #f4f6f8;
  --color-text: #1a1f28;
  --color-text-muted: #4a5361;
  --color-border: #d7dce2;
  --color-primary: #1b4d3e;
  --color-primary-dark: #123a2e;
  --color-accent: #b5482b;
  --color-error: #b3261e;
  --color-error-bg: #fdecea;
  --font-body: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN",
    "Yu Gothic", "Meiryo", system-ui, sans-serif;
  --max-width: 800px;
}

* {
  box-sizing: border-box;
}

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  padding: 0;
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.8;
  overflow-x: hidden;
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}

.container-narrow {
  max-width: 680px;
}

img {
  max-width: 100%;
  height: auto;
}

/* skip link */
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--color-primary);
  color: #fff;
  padding: 10px 16px;
  z-index: 100;
}

.skip-link:focus {
  left: 8px;
  top: 8px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* header */
.site-header {
  border-bottom: 1px solid var(--color-border);
  padding: 16px 0;
}

.brand {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-text);
}

.brand a {
  color: inherit;
  text-decoration: none;
}

.brand-tag {
  font-weight: 400;
  color: var(--color-text-muted);
  font-size: 0.85em;
  margin-left: 0.25em;
}

/* headings */
h1, h2, h3 {
  line-height: 1.5;
  font-weight: 700;
  color: var(--color-text);
}

h1 {
  font-size: 1.75rem;
  margin: 0 0 20px;
}

h2 {
  font-size: 1.4rem;
  margin: 0 0 20px;
}

h3 {
  font-size: 1.1rem;
  margin: 0 0 10px;
}

p {
  margin: 0 0 16px;
}

/* hero */
.hero {
  background-color: var(--color-bg-alt);
  padding: 56px 0 44px;
  border-bottom: 1px solid var(--color-border);
}

.hero-sub {
  font-size: 1.05rem;
  color: var(--color-text-muted);
  max-width: 640px;
}

.hero-note {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-top: 14px;
  margin-bottom: 0;
}

/* sections */
.section {
  padding: 48px 0;
  border-bottom: 1px solid var(--color-border);
}

.section-alt {
  background-color: var(--color-bg-alt);
}

.section:last-of-type {
  border-bottom: none;
}

/* buttons */
.btn {
  display: inline-block;
  font-size: 1.05rem;
  font-weight: 700;
  text-decoration: none;
  padding: 16px 28px;
  border-radius: 6px;
  border: 2px solid transparent;
  cursor: pointer;
  text-align: center;
}

.btn-primary {
  background-color: var(--color-primary);
  color: #ffffff;
}

.btn-primary:hover,
.btn-primary:focus {
  background-color: var(--color-primary-dark);
}

.btn-primary:focus-visible {
  outline: 3px solid var(--color-accent);
  outline-offset: 2px;
}

/* change list (section 2) */
.change-list {
  padding-left: 1.4em;
  margin: 0 0 20px;
}

.change-list li {
  margin-bottom: 10px;
}

/* steps (section 3) */
.steps {
  list-style: none;
  padding: 0;
  margin: 24px 0 0;
  display: grid;
  gap: 24px;
}

.steps li {
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 20px;
}

/* comparison table */
.table-wrap {
  overflow-x: auto;
  margin: 24px 0;
  -webkit-overflow-scrolling: touch;
}

.compare-table {
  border-collapse: collapse;
  width: 100%;
  min-width: 480px;
}

.compare-table th,
.compare-table td {
  border: 1px solid var(--color-border);
  padding: 12px 14px;
  text-align: center;
  font-size: 0.95rem;
}

.compare-table thead th {
  background-color: var(--color-bg-alt);
  font-weight: 700;
}

.compare-table th[scope="row"] {
  text-align: left;
  font-weight: 700;
  background-color: var(--color-bg-alt);
}

/* signup form */
.section-signup {
  background-color: var(--color-bg-alt);
}

.signup-form {
  max-width: 480px;
  margin-top: 24px;
}

.form-row {
  margin-bottom: 18px;
}

.form-row label {
  display: block;
  font-weight: 700;
  margin-bottom: 8px;
}

.form-row input[type="email"] {
  width: 100%;
  font-size: 1rem;
  padding: 12px 14px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background-color: #ffffff;
  color: var(--color-text);
}

.form-row input[type="email"]:focus {
  outline: 3px solid var(--color-primary);
  outline-offset: 1px;
}

.form-row input[aria-invalid="true"] {
  border-color: var(--color-error);
}

.form-row-checkbox {
  display: flex;
  align-items: flex-start;
  gap: 10px;
}

.form-row-checkbox input[type="checkbox"] {
  margin-top: 4px;
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

.form-row-checkbox label {
  font-weight: 400;
  margin-bottom: 0;
}

.form-error {
  color: var(--color-error);
  background-color: var(--color-error-bg);
  border-radius: 4px;
  padding: 8px 12px;
  font-size: 0.9rem;
  margin: 8px 0 0;
}

.form-note {
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-top: 14px;
}

.form-note a {
  color: var(--color-primary);
}

.form-status {
  margin-top: 16px;
  padding: 12px 14px;
  border-radius: 6px;
  font-size: 0.95rem;
}

.form-status[data-kind="pending"] {
  background-color: #fff4e0;
  color: #7a4d00;
  border: 1px solid #e8c477;
}

.form-status[data-kind="error"] {
  background-color: var(--color-error-bg);
  color: var(--color-error);
  border: 1px solid #f2b9b4;
}

.signup-thanks {
  max-width: 480px;
  margin-top: 24px;
  background-color: #ffffff;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  padding: 24px;
}

.signup-thanks h3 {
  margin-top: 0;
}

.signup-thanks p:last-child {
  margin-bottom: 0;
}

/* FAQ */
.faq-item {
  margin-bottom: 28px;
}

.faq-item:last-child {
  margin-bottom: 0;
}

/* footer */
.site-footer {
  padding: 32px 0 48px;
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

.operator-info {
  margin-bottom: 12px;
}

.footer-links a {
  color: var(--color-primary);
}

.footer-copyright {
  margin: 0;
}

/* privacy page */
.updated-note {
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

/* responsive */
@media (min-width: 640px) {
  h1 {
    font-size: 2.1rem;
  }

  h2 {
    font-size: 1.6rem;
  }

  .steps {
    grid-template-columns: repeat(3, 1fr);
  }
}