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

:root {
  --primary: #0052d9;
  --primary-light: #ebf1ff;
  --bg: #f5f7fa;
  --card-bg: #ffffff;
  --text: #1a1a1a;
  --text-secondary: #666666;
  --border: #e5e5e5;
  --success: #00a870;
  --radius: 12px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.container {
  max-width: 800px;
  margin: 0 auto;
  padding: 40px 20px;
}

/* Hero */
.hero {
  text-align: center;
  margin-bottom: 48px;
}

.hero h1 {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--primary);
}

.subtitle {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.feature-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
  transition: box-shadow 0.2s;
}

.feature-card:hover {
  box-shadow: 0 4px 16px rgba(0, 82, 217, 0.12);
}

.feature-icon {
  font-size: 2rem;
  margin-bottom: 8px;
}

.feature-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.feature-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Proxy Form */
.proxy-form {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 32px;
}

.proxy-form h2 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 20px;
  text-align: center;
}

.input-group {
  margin-bottom: 20px;
}

.input-group input {
  width: 100%;
  padding: 12px 16px;
  font-size: 1rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  outline: none;
  transition: border-color 0.2s;
}

.input-group input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-light);
}

/* Mode Select */
.mode-select {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 24px;
}

.mode-card {
  border: 2px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  cursor: pointer;
  transition: all 0.2s;
  position: relative;
}

.mode-card:hover {
  border-color: var(--primary);
  background: var(--primary-light);
}

.mode-card.active {
  border-color: var(--primary);
  background: var(--primary-light);
}

.mode-card h3 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 6px;
}

.mode-card p {
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.badge {
  display: inline-block;
  background: var(--primary);
  color: #fff;
  font-size: 0.75rem;
  padding: 2px 8px;
  border-radius: 4px;
  margin-top: 8px;
}

/* Buttons */
.btn-primary {
  display: block;
  width: 100%;
  padding: 14px;
  font-size: 1.05rem;
  font-weight: 600;
  color: #fff;
  background: var(--primary);
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s;
}

.btn-primary:hover {
  background: #003cab;
}

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* Loading */
.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-top: 20px;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.spinner {
  width: 20px;
  height: 20px;
  border: 3px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Result */
.result-section {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 32px;
  margin-bottom: 32px;
}

.result-section h2 {
  font-size: 1.3rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--success);
}

.result-section p {
  color: var(--text-secondary);
  margin-bottom: 16px;
}

.result-box {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 16px;
  margin-bottom: 16px;
}

.result-url {
  flex: 1;
  word-break: break-all;
  color: var(--primary);
  text-decoration: none;
  font-size: 0.95rem;
}

.result-url:hover {
  text-decoration: underline;
}

.btn-copy {
  padding: 8px 16px;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--primary);
  background: var(--primary-light);
  border: 1px solid var(--primary);
  border-radius: 6px;
  cursor: pointer;
  white-space: nowrap;
}

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

.tip {
  font-size: 0.85rem;
  color: var(--text-secondary);
  background: #fff8e6;
  border-left: 3px solid #faad14;
  padding: 10px 14px;
  border-radius: 0 6px 6px 0;
}

/* Footer */
.footer {
  text-align: center;
  color: var(--text-secondary);
  font-size: 0.85rem;
  line-height: 1.8;
}

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

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

.disclaimer {
  margin-top: 12px;
  font-size: 0.8rem;
  color: #999;
}

/* Responsive */
@media (max-width: 600px) {
  .features {
    grid-template-columns: 1fr;
  }
  .mode-select {
    grid-template-columns: 1fr;
  }
  .hero h1 {
    font-size: 1.5rem;
  }
}