/* 现代简约风格 */
:root {
  --accent: #2563eb;
  --accent-hover: #1d4ed8;
  --accent-ring: rgba(37, 99, 235, 0.12);
  --bg: #f1f5f9;
  --card: #ffffff;
  --text-primary: #0f172a;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  --border: #e2e8f0;
  --success-bg: #f0fdf4;
  --success-bg-hover: #dcfce7;
  --success-border: #bbf7d0;
  --error: #ef4444;
  --radius: 12px;
  --shadow: 0 1px 2px rgba(0,0,0,0.04), 0 4px 24px rgba(0,0,0,0.07);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  min-height: 100vh;
  background: var(--bg);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

/* ── Container ── */
.container {
  background: var(--card);
  border-radius: 20px;
  box-shadow: var(--shadow);
  padding: 44px 40px 40px;
  width: 100%;
  max-width: 640px;
}

/* ── Header ── */
.header {
  text-align: center;
  margin-bottom: 36px;
}

.logo {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 52px;
  height: 52px;
  background: var(--accent);
  color: #fff;
  border-radius: 14px;
  margin-bottom: 18px;
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.3);
}

.header h1 {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.4px;
  margin-bottom: 6px;
}

.subtitle {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* ── Input Group ── */
.input-group {
  display: flex;
  gap: 10px;
  margin-bottom: 16px;
}

.input-group input[type="text"] {
  flex: 1;
  padding: 12px 16px;
  border: 1.5px solid var(--border);
  border-radius: 10px;
  font-size: 0.95rem;
  font-family: inherit;
  color: var(--text-primary);
  background: #fff;
  outline: none;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.input-group input[type="text"]:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-ring);
}

.input-group input[type="text"]::placeholder {
  color: var(--text-muted);
}

.input-group button {
  padding: 12px 24px;
  background: var(--accent);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 0.95rem;
  font-weight: 500;
  font-family: inherit;
  cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  white-space: nowrap;
  box-shadow: 0 2px 8px rgba(37, 99, 235, 0.25);
}

.input-group button:hover {
  background: var(--accent-hover);
  box-shadow: 0 4px 14px rgba(37, 99, 235, 0.35);
}

.input-group button:active {
  transform: scale(0.97);
}

.input-group button:disabled {
  opacity: 0.55;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

/* ── Status ── */
#status {
  font-size: 0.875rem;
  min-height: 1.4em;
  text-align: center;
  color: var(--text-secondary);
  transition: color 0.2s;
}

#status.loading {
  color: var(--text-secondary);
}

#status.error {
  color: var(--error);
  font-weight: 500;
}

/* ── Result Box ── */
#result {
  margin-top: 20px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

/* ── URL List ── */
.url-section {
  margin-bottom: 0;
}

.url-section h3 {
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--text-muted);
  padding: 12px 16px 10px;
  border-bottom: 1px solid var(--border);
  background: #fafafa;
}

.url-section + .url-section {
  border-top: 1px solid var(--border);
}

.url-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 11px 16px;
  border-bottom: 1px solid var(--border);
  transition: background 0.15s;
}

.url-item:last-child {
  border-bottom: none;
}

.url-item:hover {
  background: #f8fafc;
}

.url-item.final-url {
  background: var(--success-bg);
}

.url-item.final-url:hover {
  background: var(--success-bg-hover);
}

.url-index {
  font-size: 0.72rem;
  font-weight: 600;
  color: var(--text-muted);
  min-width: 20px;
  text-align: center;
  flex-shrink: 0;
}

.url-link {
  flex: 1;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.875rem;
  word-break: break-all;
  line-height: 1.5;
  transition: color 0.15s;
}

.url-link:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

.url-link.clicked,
.url-link:visited {
  color: var(--text-secondary);
}

.copy-btn {
  flex-shrink: 0;
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border);
  padding: 4px 11px;
  border-radius: 6px;
  font-size: 0.73rem;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
}

.copy-btn:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.copy-btn:active {
  transform: scale(0.95);
}

/* ── Toast ── */
.copy-toast {
  position: fixed;
  bottom: 28px;
  left: 50%;
  transform: translateX(-50%) translateY(6px);
  background: var(--text-primary);
  color: #fff;
  padding: 10px 22px;
  border-radius: 8px;
  font-size: 0.875rem;
  font-weight: 500;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
  z-index: 1000;
  opacity: 0;
  transition: opacity 0.22s ease, transform 0.22s ease;
  pointer-events: none;
}

.copy-toast.error {
  background: var(--error);
}

.copy-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ── Responsive ── */
@media (max-width: 640px) {
  body {
    padding: 16px;
    align-items: flex-start;
    padding-top: 48px;
  }

  .container {
    padding: 32px 20px 28px;
  }

  .input-group {
    flex-direction: column;
  }

  .input-group button {
    width: 100%;
  }
}

@media (max-width: 480px) {
  .input-group input[type="text"] {
    font-size: 16px; /* prevent iOS zoom */
  }

  .input-group button {
    font-size: 16px;
  }

  .copy-toast {
    bottom: 16px;
    left: 16px;
    right: 16px;
    width: auto;
    text-align: center;
    transform: translateY(6px);
  }

  .copy-toast.show {
    transform: translateY(0);
  }
}