*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg: #0a0f1e;
  --surface: #111827;
  --surface2: #1a2235;
  --border: #1e3a5f;
  --accent: #00d4ff;
  --accent2: #0077ff;
  --text: #e2e8f0;
  --text-muted: #64748b;
  --success: #10b981;
  --danger: #ef4444;
  --radius: 12px;
}

body {
  background-color: var(--bg);
  color: var(--text);
  font-family: 'Syne', sans-serif;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem 1rem;
  background-image:
    radial-gradient(ellipse at 20% 20%, rgba(0, 119, 255, 0.07) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 80%, rgba(0, 212, 255, 0.05) 0%, transparent 60%);
}

/* ── HEADER ── */
header {
  text-align: center;
  margin-bottom: 2.5rem;
  animation: fadeDown 0.6s ease both;
}

.badge {
  display: inline-block;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--accent);
  border: 1px solid var(--border);
  padding: 0.3rem 0.9rem;
  border-radius: 100px;
  margin-bottom: 1rem;
  background: rgba(0, 212, 255, 0.05);
}

h1 {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1.1;
}

h1 span {
  color: var(--accent);
}

.subtitle {
  margin-top: 0.6rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  font-weight: 400;
}

/* ── CARD ── */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 2rem;
  width: 100%;
  max-width: 520px;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.1s;
  box-shadow: 0 0 40px rgba(0, 119, 255, 0.07);
}

/* ── OPÇÕES ── */
.options {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.option-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}

.option-label {
  font-size: 0.9rem;
  color: var(--text-muted);
  font-weight: 600;
  letter-spacing: 0.03em;
}

/* Toggle switch */
.toggle {
  position: relative;
  width: 46px;
  height: 26px;
  flex-shrink: 0;
}

.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}

.toggle-slider {
  position: absolute;
  inset: 0;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 100px;
  cursor: pointer;
  transition: background 0.25s, border-color 0.25s;
}

.toggle-slider::before {
  content: '';
  position: absolute;
  width: 18px;
  height: 18px;
  left: 3px;
  top: 50%;
  transform: translateY(-50%);
  background: var(--text-muted);
  border-radius: 50%;
  transition: transform 0.25s, background 0.25s;
}

.toggle input:checked + .toggle-slider {
  background: rgba(0, 212, 255, 0.15);
  border-color: var(--accent);
}

.toggle input:checked + .toggle-slider::before {
  transform: translate(20px, -50%);
  background: var(--accent);
}

/* Quantidade */
.qty-control {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.qty-btn {
  width: 30px;
  height: 30px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--surface2);
  color: var(--text);
  font-size: 1.1rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: border-color 0.2s, background 0.2s;
  line-height: 1;
}

.qty-btn:hover {
  border-color: var(--accent);
  background: rgba(0, 212, 255, 0.08);
}

.qty-value {
  min-width: 28px;
  text-align: center;
  font-weight: 700;
  font-size: 0.95rem;
}

/* ── BOTÃO GERAR ── */
.btn-generate {
  width: 100%;
  padding: 0.9rem;
  border: none;
  border-radius: var(--radius);
  background: linear-gradient(135deg, var(--accent2), var(--accent));
  color: #fff;
  font-family: 'Syne', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  cursor: pointer;
  transition: opacity 0.2s, transform 0.15s;
  margin-bottom: 1.5rem;
}

.btn-generate:hover {
  opacity: 0.9;
  transform: translateY(-1px);
}

.btn-generate:active {
  transform: translateY(0);
}

/* ── RESULTADO ── */
.results {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  min-height: 60px;
}

.cpf-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.7rem 1rem;
  animation: popIn 0.3s ease both;
}

.cpf-number {
  font-family: 'Share Tech Mono', monospace;
  font-size: 1.15rem;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.btn-copy {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-size: 0.75rem;
  font-family: 'Syne', sans-serif;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 0.3rem 0.7rem;
  border-radius: 6px;
  cursor: pointer;
  white-space: nowrap;
  transition: color 0.2s, border-color 0.2s, background 0.2s;
}

.btn-copy:hover {
  color: var(--accent);
  border-color: var(--accent);
  background: rgba(0, 212, 255, 0.06);
}

.btn-copy.copied {
  color: var(--success);
  border-color: var(--success);
  background: rgba(16, 185, 129, 0.08);
}

/* placeholder */
.placeholder {
  text-align: center;
  color: var(--text-muted);
  font-size: 0.9rem;
  padding: 1.5rem 0;
}

/* ── FOOTER ── */
footer {
  margin-top: 2rem;
  color: var(--text-muted);
  font-size: 0.8rem;
  text-align: center;
  animation: fadeUp 0.6s ease both;
  animation-delay: 0.2s;
}

footer a {
  color: var(--accent);
  text-decoration: none;
}

footer a:hover {
  text-decoration: underline;
}

/* ── AVISO ── */
.warning {
  margin-top: 1.2rem;
  padding: 0.7rem 1rem;
  background: rgba(239, 68, 68, 0.07);
  border: 1px solid rgba(239, 68, 68, 0.25);
  border-radius: 8px;
  font-size: 0.8rem;
  color: #fca5a5;
  text-align: center;
  line-height: 1.5;
}

/* ── ANIMATIONS ── */
@keyframes fadeDown {
  from { opacity: 0; transform: translateY(-20px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(20px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes popIn {
  from { opacity: 0; transform: scale(0.96); }
  to   { opacity: 1; transform: scale(1); }
}

/* ── RESPONSIVE ── */
@media (max-width: 420px) {
  .card { padding: 1.4rem; }
  .cpf-number { font-size: 1rem; }
}