:root {
  color-scheme: light;
  --bg: #f4f7fb;
  --surface: #ffffff;
  --surface-soft: #f8fafc;
  --text: #172033;
  --muted: #637083;
  --border: #dce3ed;
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-soft: #eaf1ff;
  --ok: #15803d;
  --ok-soft: #ecfdf3;
  --warning: #a16207;
  --warning-soft: #fff8e6;
  --danger: #b42318;
  --danger-soft: #fff0ee;
  --shadow: 0 16px 40px rgba(25, 45, 79, 0.08);
  --radius-lg: 20px;
  --radius-md: 12px;
  --focus: 0 0 0 3px rgba(37, 99, 235, 0.25);
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0f1724;
  --surface: #182233;
  --surface-soft: #111b2a;
  --text: #eef4ff;
  --muted: #a7b3c6;
  --border: #2e3b50;
  --primary: #74a2ff;
  --primary-hover: #94b8ff;
  --primary-soft: #1d3159;
  --ok: #65d68a;
  --ok-soft: #173426;
  --warning: #f5c45e;
  --warning-soft: #3a2c13;
  --danger: #ff8d86;
  --danger-soft: #42201f;
  --shadow: 0 18px 48px rgba(0, 0, 0, 0.25);
  --focus: 0 0 0 3px rgba(116, 162, 255, 0.3);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-width: 320px;
  background:
    radial-gradient(circle at 8% 2%, rgba(37, 99, 235, 0.1), transparent 30rem),
    var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans JP", "Yu Gothic UI", sans-serif;
  line-height: 1.7;
  transition: background-color 0.2s ease, color 0.2s ease;
}

button,
textarea,
select {
  font: inherit;
}

button,
select,
summary {
  cursor: pointer;
}

button:focus-visible,
textarea:focus-visible,
select:focus-visible,
summary:focus-visible {
  outline: none;
  box-shadow: var(--focus);
}

a {
  color: inherit;
}

code {
  padding: 0.1em 0.35em;
  border: 1px solid var(--border);
  border-radius: 5px;
  background: var(--surface-soft);
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.9em;
}

.site-header {
  position: sticky;
  z-index: 10;
  top: 0;
  border-bottom: 1px solid color-mix(in srgb, var(--border) 80%, transparent);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: blur(14px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: min(1120px, calc(100% - 32px));
  min-height: 64px;
  margin: 0 auto;
}

.brand {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  color: var(--text);
  font-weight: 750;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border-radius: 10px;
  background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: white;
  font-weight: 800;
}

.icon-button,
.text-button {
  border: 0;
  background: transparent;
  color: var(--text);
}

.icon-button {
  display: inline-flex;
  gap: 7px;
  align-items: center;
  min-height: 40px;
  padding: 7px 10px;
  border-radius: 10px;
}

.icon-button:hover,
.text-button:hover {
  background: var(--primary-soft);
  color: var(--primary);
}

main {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.hero {
  max-width: 820px;
  padding: 72px 0 38px;
}

.eyebrow,
.step-label {
  margin: 0;
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.1em;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  margin: 8px 0 16px;
  font-size: clamp(2rem, 5vw, 3.6rem);
  line-height: 1.18;
  letter-spacing: -0.035em;
}

h2 {
  margin: 4px 0 0;
  font-size: clamp(1.35rem, 3vw, 1.8rem);
  line-height: 1.35;
}

h3 {
  margin: 8px 0 6px;
  font-size: 1.08rem;
}

.hero-copy {
  max-width: 720px;
  margin: 0;
  color: var(--muted);
  font-size: 1.08rem;
}

.privacy-note {
  display: inline-flex;
  gap: 8px;
  align-items: center;
  margin-top: 22px;
  padding: 8px 12px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--muted);
  font-size: 0.9rem;
}

.privacy-note span {
  color: var(--ok);
  font-size: 0.75rem;
}

.tool-shell {
  display: grid;
  gap: 22px;
}

.card {
  padding: clamp(20px, 4vw, 32px);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  background: var(--surface);
  box-shadow: var(--shadow);
}

.section-heading {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 18px;
}

.text-button {
  flex: 0 0 auto;
  padding: 7px 10px;
  border-radius: 9px;
  color: var(--primary);
  font-size: 0.92rem;
  font-weight: 700;
}

textarea {
  display: block;
  width: 100%;
  min-height: 230px;
  padding: 16px;
  resize: vertical;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--surface-soft);
  color: var(--text);
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-size: 0.9rem;
  line-height: 1.65;
}

textarea::placeholder {
  color: var(--muted);
  opacity: 0.75;
}

.field-help,
.input-message,
.copy-message,
.empty-filter {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 0.88rem;
}

.input-message {
  color: var(--danger);
  font-weight: 700;
}

.action-row,
.result-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.action-row {
  margin-top: 20px;
}

.button {
  min-height: 46px;
  padding: 10px 18px;
  border: 1px solid transparent;
  border-radius: 11px;
  font-weight: 750;
  transition: transform 0.15s ease, background-color 0.15s ease, border-color 0.15s ease;
}

.button:active {
  transform: translateY(1px);
}

.button-primary {
  background: var(--primary);
  color: #fff;
}

[data-theme="dark"] .button-primary {
  color: #0b1730;
}

.button-primary:hover {
  background: var(--primary-hover);
}

.button-secondary,
.button-compact {
  border-color: var(--border);
  background: var(--surface-soft);
  color: var(--text);
}

.button-secondary:hover,
.button-compact:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.button-compact {
  min-height: 40px;
  padding: 7px 12px;
  font-size: 0.9rem;
}

.filter-select {
  min-height: 40px;
  padding: 7px 34px 7px 11px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface-soft);
  color: var(--text);
}

.summary-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin: 4px 0 22px;
}

.summary-item {
  display: flex;
  flex-direction: column;
  padding: 13px 15px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface-soft);
}

.summary-label {
  color: var(--muted);
  font-size: 0.8rem;
}

.summary-item strong {
  font-size: 1.45rem;
  line-height: 1.3;
}

.summary-ok strong {
  color: var(--ok);
}

.summary-review strong {
  color: var(--warning);
}

.summary-invalid strong {
  color: var(--danger);
}

.result-list {
  display: grid;
  gap: 12px;
}

.result-card {
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--surface-soft);
  overflow: hidden;
}

.result-card[hidden] {
  display: none;
}

.result-card-header {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  padding: 14px 16px;
}

.status-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 88px;
  min-height: 30px;
  padding: 4px 9px;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 800;
}

.status-ok {
  background: var(--ok-soft);
  color: var(--ok);
}

.status-review {
  background: var(--warning-soft);
  color: var(--warning);
}

.status-invalid {
  background: var(--danger-soft);
  color: var(--danger);
}

.result-url-wrap {
  min-width: 0;
}

.result-line-number {
  color: var(--muted);
  font-size: 0.78rem;
}

.result-url {
  display: block;
  margin-top: 2px;
  overflow-wrap: anywhere;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.86rem;
  line-height: 1.45;
}

.copy-url-button {
  min-height: 34px;
  padding: 5px 9px;
  border: 1px solid var(--border);
  border-radius: 9px;
  background: var(--surface);
  color: var(--text);
  font-size: 0.8rem;
  font-weight: 700;
}

.copy-url-button:hover {
  color: var(--primary);
  border-color: var(--primary);
}

.result-details {
  padding: 0 16px 16px;
}

.parameter-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
  margin: 0 0 12px;
}

.parameter-item {
  min-width: 0;
  padding: 9px 10px;
  border: 1px solid var(--border);
  border-radius: 9px;
  background: var(--surface);
}

.parameter-name {
  display: block;
  color: var(--muted);
  font-size: 0.72rem;
}

.parameter-value {
  display: block;
  overflow-wrap: anywhere;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: 0.82rem;
}

.issue-list {
  display: grid;
  gap: 7px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.issue-item {
  padding: 8px 10px;
  border-left: 3px solid var(--warning);
  border-radius: 5px;
  background: var(--warning-soft);
  color: var(--text);
  font-size: 0.86rem;
}

.issue-item.issue-error {
  border-left-color: var(--danger);
  background: var(--danger-soft);
}

.no-issues {
  margin: 0;
  color: var(--ok);
  font-size: 0.9rem;
  font-weight: 700;
}

.content-section {
  padding: 62px 0 0;
}

.content-section > h2 {
  margin-bottom: 20px;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.feature-card {
  padding: 22px;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: var(--surface);
}

.feature-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.93rem;
}

.feature-number {
  color: var(--primary);
  font-size: 0.78rem;
  font-weight: 800;
}

.prose {
  max-width: 820px;
}

.prose ol {
  padding-left: 1.5rem;
}

.prose li + li {
  margin-top: 8px;
}

.notice-box {
  margin-top: 22px;
  padding: 17px 19px;
  border: 1px solid var(--border);
  border-left: 4px solid var(--primary);
  border-radius: 10px;
  background: var(--surface);
}

.notice-box p {
  margin: 4px 0 0;
  color: var(--muted);
}

.faq-section {
  max-width: 820px;
  padding-bottom: 72px;
}

.faq-section details {
  border-top: 1px solid var(--border);
}

.faq-section details:last-child {
  border-bottom: 1px solid var(--border);
}

.faq-section summary {
  padding: 16px 4px;
  font-weight: 750;
}

.faq-section details p {
  margin: -4px 4px 17px;
  color: var(--muted);
}

footer {
  padding: 28px 16px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  text-align: center;
  font-size: 0.86rem;
}

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

@media (max-width: 760px) {
  .header-inner,
  main {
    width: min(100% - 24px, 1120px);
  }

  .hero {
    padding-top: 46px;
  }

  .theme-label {
    display: none;
  }

  .card {
    border-radius: 16px;
  }

  .results-heading-row {
    display: block;
  }

  .result-actions {
    margin-top: 14px;
  }

  .summary-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .result-card-header {
    grid-template-columns: auto minmax(0, 1fr);
  }

  .copy-url-button {
    grid-column: 1 / -1;
    justify-self: start;
  }

  .parameter-list,
  .feature-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 460px) {
  .section-heading {
    display: block;
  }

  .section-heading .text-button {
    margin-top: 8px;
  }

  .action-row .button,
  .result-actions .button,
  .filter-select {
    width: 100%;
  }

  .result-actions {
    display: grid;
  }

  .result-card-header {
    align-items: start;
  }

  .status-badge {
    min-width: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}