:root {
  --bg: #0a0a0b;
  --bg-card: #141416;
  --bg-input: #1c1c1f;
  --text: #e4e4e7;
  --text-secondary: #a1a1aa;
  --text-muted: #71717a;
  --border: #27272a;
  --primary: #6366f1;
  --primary-hover: #818cf8;
  --success: #22c55e;
  --error: #ef4444;
  --radius: 8px;
  --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: ui-monospace, 'SF Mono', 'Fira Code', 'Fira Mono', Menlo, monospace;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #fafafa;
    --bg-card: #ffffff;
    --bg-input: #f4f4f5;
    --text: #18181b;
    --text-secondary: #52525b;
    --text-muted: #a1a1aa;
    --border: #e4e4e7;
  }
}

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

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.container { max-width: 680px; margin: 0 auto; padding: 0 20px; width: 100%; }

.nav {
  padding: 14px 0;
  border-bottom: 1px solid var(--border);
  background: var(--bg-card);
}

.nav .container { display: flex; justify-content: space-between; align-items: center; }

.nav-brand { font-size: 1.2rem; font-weight: 700; color: var(--primary); text-decoration: none; }

.nav-links { display: flex; gap: 20px; }

.nav-links a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.9rem;
  transition: color .2s;
}

.nav-links a:hover { color: var(--text); }

main { flex: 1; padding: 40px 0; }

h1 { font-size: 1.6rem; margin-bottom: 20px; }
h2 { font-size: 1.15rem; margin-bottom: 10px; }
p { color: var(--text-secondary); margin-bottom: 14px; }

.hero { text-align: center; padding: 50px 0 36px; }
.hero h1 { font-size: 2.2rem; margin-bottom: 6px; }
.hero-subtitle { font-size: 1.05rem; color: var(--text-muted); }

.cards-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }

@media (max-width: 600px) {
  .cards-grid { grid-template-columns: 1fr; }
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  margin-bottom: 24px;
}

.card.error { border-color: var(--error); }
.card.success { border-color: var(--success); }

.feature-card { display: flex; flex-direction: column; }
.feature-card p { flex: 1; }

.feature-list { list-style: none; margin: 14px 0 22px; }
.feature-list li { padding: 5px 0; color: var(--text-secondary); font-size: 0.88rem; }
.feature-list li::before { content: '\2713 '; color: var(--success); }

.form-group { margin-bottom: 14px; }

.form-row { display: flex; gap: 14px; align-items: flex-end; }
.form-row .form-group { flex: 1; }

label { display: block; font-size: 0.83rem; font-weight: 600; margin-bottom: 5px; color: var(--text-secondary); }
.label-note { font-weight: 400; color: var(--text-muted); }

.input {
  width: 100%;
  padding: 10px 13px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--font);
  font-size: 0.93rem;
  transition: border-color .2s;
}

.input:focus { outline: none; border-color: var(--primary); }

.textarea {
  resize: vertical;
  min-height: 120px;
  font-family: var(--font-mono);
  font-size: 0.88rem;
  line-height: 1.5;
}

select.input { cursor: pointer; }

.checkbox-group { display: flex; align-items: center; padding-top: 20px; }

.checkbox-label {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.checkbox-label input[type="checkbox"] { width: 17px; height: 17px; accent-color: var(--primary); }

.btn {
  display: inline-block;
  padding: 9px 18px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 0.88rem;
  cursor: pointer;
  text-decoration: none;
  transition: all .2s;
  font-family: var(--font);
  line-height: 1.4;
}

.btn:hover { background: var(--border); }

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

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

.btn-large {
  width: 100%;
  padding: 13px;
  font-size: 0.95rem;
  font-weight: 600;
  text-align: center;
}

.btn:disabled { opacity: .5; cursor: not-allowed; }

.link-copy { display: flex; gap: 8px; margin: 14px 0; }
.link-copy .input { flex: 1; font-family: var(--font-mono); font-size: 0.82rem; cursor: default; }
.link-copy .btn { white-space: nowrap; }

.paste-meta {
  display: flex;
  gap: 20px;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-bottom: 14px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}

.paste-text {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 0.83rem;
  line-height: 1.5;
  overflow-x: auto;
  white-space: pre-wrap;
  word-break: break-word;
  max-height: 70vh;
  overflow-y: auto;
  margin-bottom: 14px;
}

.error-text { color: var(--error); font-size: 0.88rem; margin-bottom: 10px; }

.footer {
  text-align: center;
  padding: 22px 0;
  border-top: 1px solid var(--border);
  font-size: 0.83rem;
  color: var(--text-muted);
}