/* 两页共用的配色与基础外观；页面布局留在各自样式表中。 */
:root {
  --bg: #f5f0e8;
  --card: rgba(255, 254, 249, 0.65);
  --border: #d4c8b0;
  --text: #3d3226;
  --text-soft: #5f5146;
  --text-dim: #8b7d6b;
  --accent: #8b2500;
  --accent-light: #c75b3a;
  --tile-bg: #faf7f0;
  --tile-hover: #f0e6d2;
  --tile-selected: #8b2500;
  --tile-selected-text: #fff;
  --placeholder: #c0b8a8;
  --tag-bg: #fef5f0;
  --tag-border: #f0d0b8;
  --shadow: 0 1px 8px rgba(0, 0, 0, 0.05);
}

/* 基础字体与页面底色 */
* { margin: 0; padding: 0; box-sizing: border-box; }

html {
  min-height: 100%;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  text-size-adjust: 100%;
}

body {
  font-family: "PingFang SC", "Noto Serif SC", "Source Han Serif SC", "Hiragino Mincho Pro", "Songti SC", serif;
  background: radial-gradient(ellipse at 50% 30%, #faf6ec 0%, #efe8d6 60%, #e0d8c0 100%);
  color: var(--text);
  min-height: 100vh;
  min-height: 100dvh;
  padding: 2.3rem 0.8rem;
  overflow-x: hidden;
}

/* 卡片与输入框：只共享外观，不设置布局和尺寸约束。 */
.card,
.guestbook-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.header p,
.support-link,
.guestbook-heading p {
  color: var(--text-dim);
  font-family: inherit;
  font-size: 0.9rem;
  font-weight: 400;
  line-height: 1.2;
  letter-spacing: 0;
}

.input-group label,
.form-field label {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-soft);
}

.input-group input,
.form-field input,
.form-field textarea {
  font-family: inherit;
  font-size: 0.95rem;
  padding: 0.4rem 0.55rem;
  border: 1.5px solid var(--border);
  border-radius: 6px;
  background: var(--tile-bg);
  color: var(--text);
  outline: none;
}

.input-group input:focus,
.form-field input:focus,
.form-field textarea:focus {
  border-color: var(--accent-light);
}

/* 按钮的禁用状态和页面特有交互仍由各页定义。 */
.btn,
.submit-button {
  font-size: 0.95rem;
  font-weight: 600;
  padding: 0.42rem 1rem;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  letter-spacing: 0.04em;
}

.btn-primary,
.submit-button {
  background: var(--accent);
  color: #fff;
}

.btn-primary:hover,
.submit-button:hover:not(:disabled) {
  background: #7a1f00;
}

/* 两种页脚链接只共用外观；网格位置与固定定位不能合并。 */
.footer-link,
.site-footer-link {
  color: var(--accent);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: rgba(139, 37, 0, 0.35);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.16rem;
}

.footer-link:hover,
.site-footer-link:hover {
  color: #7a1f00;
  text-decoration-color: rgba(139, 37, 0, 0.65);
}