:root {
  --bg-color: #f5f5f5;
  --text-color: #333;
  --card-bg: #fff;
  --card-shadow: rgba(0, 0, 0, 0.08);
  --sentence-color: #666;
  --link-color: #1677ff;
  --link-hover-color: #4096ff;
  --footer-color: #555;
  --footer-hover-color: #000;
}

[data-theme='dark'] {
  --bg-color: #1a1a1a;
  --text-color: #e0e0e0;
  --card-bg: #2d2d2d;
  --card-shadow: rgba(0, 0, 0, 0.3);
  --sentence-color: #a0a0a0;
  --link-color: #4096ff;
  --link-hover-color: #69b1ff;
  --footer-color: #a0a0a0;
  --footer-hover-color: #c0c0c0;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.page-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-start;
  padding: 20px;
  padding-top: 20vh;
}

.message-card {
  background-color: var(--card-bg);
  padding: 24px 20px;
  border-radius: 8px;
  box-shadow: 0 4px 16px var(--card-shadow);
  max-width: 480px;
  width: 100%;
  line-height: 1.7;
  font-size: 15px;
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.sentence-block {
  margin-top: 12px;
  text-align: right;
  font-size: 13px;
  color: var(--sentence-color);
  max-width: 480px;
  width: 100%;
  transition: color 0.3s ease;
}

.sentence-block > div + div {
  margin-top: 2px;
}

.line + .line {
  margin-top: 8px;
}

.domain {
  font-weight: 600;
}

a {
  color: var(--link-color);
  text-decoration: underline;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--link-hover-color);
}

.theme-toggle {
  position: fixed;
  top: 20px;
  right: 20px;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background-color: var(--card-bg);
  border: 2px solid var(--footer-color);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 2px 8px var(--card-shadow);
  transition: all 0.3s ease;
  z-index: 1000;
}

.theme-toggle:hover {
  transform: scale(1.1);
  box-shadow: 0 4px 12px var(--card-shadow);
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  fill: var(--footer-color);
  transition: opacity 0.3s ease, fill 0.3s ease;
}

.theme-toggle .sun-icon {
  display: none;
}

.theme-toggle .moon-icon {
  display: none;
}

.theme-toggle .auto-icon {
  display: none;
}

/* 根据 data-theme-setting 显示相应图标 */
[data-theme-setting='light'] .theme-toggle .sun-icon {
  display: block;
}

[data-theme-setting='dark'] .theme-toggle .moon-icon {
  display: block;
}

[data-theme-setting='auto'] .theme-toggle .auto-icon {
  display: block;
}

.footer {
  text-align: center;
  padding: 16px 0 24px;
  font-size: 13px;
  color: var(--footer-color);
  transition: color 0.3s ease;
}

.footer p {
  margin: 0;
}

.footer a {
  color: var(--footer-color);
  text-decoration: none;
  transition: color 0.3s ease;
}

.footer a:hover {
  color: var(--footer-hover-color);
}

@media (max-width: 480px) {
  .message-card {
    padding: 20px 16px;
    font-size: 14px;
  }
  
  .theme-toggle {
    top: 10px;
    right: 10px;
    width: 22px;
    height: 22px;
  }
  
  .theme-toggle img {
    width: 18px;
    height: 18px;
  }
}