:root {
  --fg: #111827;
  --muted: #6b7280;
  --bg: #ffffff;
  --surface: #f9fafb;
  --border: #e5e7eb;
  --accent: #2563eb;
  --accent-fg: #ffffff;
  --error: #b91c1c;
  --radius: 10px;
  --shadow: 0 12px 32px rgba(15, 23, 42, 0.08);
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
}

body {
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  color: var(--fg);
  background: var(--surface);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  padding: 32px 16px;
}

main {
  width: 100%;
  max-width: 560px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 32px;
}

h1 {
  font-size: 1.75rem;
  margin: 0 0 8px;
  line-height: 1.2;
}

.subhead {
  color: var(--muted);
  margin: 0 0 24px;
}

form {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 24px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.field span {
  font-size: 0.875rem;
  font-weight: 500;
}

input[type="text"],
input[type="email"],
input[type="tel"] {
  font: inherit;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  color: var(--fg);
}

input:focus {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
  border-color: var(--accent);
}

button[type="submit"] {
  margin-top: 8px;
  padding: 12px 16px;
  background: var(--accent);
  color: var(--accent-fg);
  border: 0;
  border-radius: 8px;
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}

button[type="submit"]:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.error {
  color: var(--error);
  font-size: 0.875rem;
  margin: 0;
}

.hp {
  position: absolute;
  left: -10000px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.success p,
.not-found p,
.empty {
  color: var(--muted);
}

.index ul {
  list-style: none;
  padding: 0;
  margin: 16px 0 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.index li a {
  display: block;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  color: var(--fg);
  transition: border-color 0.15s, transform 0.15s;
}

.index li a:hover {
  border-color: var(--accent);
}

a {
  color: var(--accent);
}

body.iframe {
  background: transparent;
  min-height: 0;
  padding: 0;
}

body.iframe main {
  border: 0;
  box-shadow: none;
  border-radius: 0;
  padding: 24px;
  max-width: 100%;
}