:root {
  --bg: #0f172a;       /* slate-900 */
  --panel: #111827;    /* gray-900 */
  --muted: #94a3b8;    /* slate-400 */
  --fg: #e5e7eb;       /* gray-200 */
  --brand: #22d3ee;    /* cyan-400 */
  --accent: #a78bfa;   /* violet-400 */
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: radial-gradient(1200px 600px at 10% -10%, #1f2937, transparent),
              radial-gradient(1200px 600px at 110% 10%, #0e7490, transparent),
              var(--bg);
  color: var(--fg);
  font: 16px/1.6 system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue",
        Arial, "Noto Sans", "Apple Color Emoji", "Segoe UI Emoji";
}

.container {
  max-width: 760px;
  margin: 48px auto;
  padding: 24px;
  background: rgba(17, 24, 39, 0.7);
  border: 1px solid rgba(148, 163, 184, 0.2);
  border-radius: 16px;
  backdrop-filter: blur(6px);
}

h1 {
  margin: 0 0 8px;
  font-size: 32px;
  letter-spacing: -0.02em;
}

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

form label {
  display: block;
  margin: 12px 0;
  font-weight: 600;
}

input, select, button {
  width: 100%;
  padding: 12px 14px;
  margin-top: 8px;
  border-radius: 10px;
  border: 1px solid rgba(148, 163, 184, 0.25);
  background: #0b1220;
  color: var(--fg);
  outline: none;
}

input:focus, select:focus {
  border-color: var(--brand);
  box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.25);
}

button {
  cursor: pointer;
  background: linear-gradient(90deg, var(--brand), var(--accent));
  border: 0;
  font-weight: 700;
  margin-top: 18px;
}

.grid {
  display: grid;
  grid-template-columns: 1fr 220px;
  gap: 16px;
}
@media (max-width: 640px) {
  .grid { grid-template-columns: 1fr; }
}

.result {
  margin-top: 28px;
  padding: 16px;
  border: 1px dashed rgba(148,163,184,0.35);
  border-radius: 12px;
  background: rgba(2,6,23,0.4);
}
.result.hidden { display: none; }
.result h2 { margin: 0 0 8px; }
.result p { margin: 0 0 10px; }

#short-url {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 14px;
  padding: 8px 10px;
  background: #0b1220;
  border-radius: 8px;
  border: 1px solid rgba(148,163,184,0.2);
  word-break: break-all;
}

.actions {
  display: flex; gap: 10px; align-items: center; margin-top: 10px;
}
.actions .btn, .actions button {
  display: inline-block; width: auto;
  padding: 10px 14px; border-radius: 10px; text-decoration: none;
  background: #0b1220; border: 1px solid rgba(148,163,184,0.25);
  color: var(--fg); font-weight: 600;
}

.hint { color: var(--muted); font-size: 14px; margin-top: 8px; }

footer { margin-top: 24px; color: var(--muted); font-size: 14px; text-align: center; }
.footer-donate {
  margin-top: 12px;
  text-align: center;
}

.donate-btn {
  display: inline-block;
  background: linear-gradient(90deg, #00c6ff, #7d2ae8);
  color: #fff;
  font-weight: 600;
  padding: 10px 20px;
  border-radius: 6px;
  text-decoration: none;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.donate-btn:hover {
  transform: scale(1.05);
  opacity: 0.9;
}