/* css/layout.css */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 48px 24px 80px;
  position: relative;
  z-index: 1;
}

.header { text-align: center; margin-bottom: 28px; position: relative; }
.header h1 {
  font-size: 36px;
  font-weight: 700;
  letter-spacing: 1px;
  background: linear-gradient(135deg, #fff 0%, #c7d2fe 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 10px;
}
.header p { color: var(--text-secondary); font-size: 15px; letter-spacing: 0.5px; }
.header-tools {
  position: absolute; top: 0; right: 0;
  display: flex; gap: 8px; flex-wrap: wrap; justify-content: flex-end;
}

.footer {
  margin-top: 60px; padding-top: 28px;
  border-top: 1px solid var(--card-border);
  text-align: center; font-size: 13px; color: var(--text-muted);
}

.back-top {
  position: fixed; right: 24px; bottom: 24px;
  width: 44px; height: 44px; padding: 0;
  border-radius: 50%;
  border: 1px solid var(--card-border);
  background: var(--card-bg);
  color: var(--text-primary);
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  opacity: 0; pointer-events: none;
  transform: translateY(10px);
  transition: var(--transition);
  z-index: 60;
}
.back-top.show { opacity: 1; pointer-events: auto; transform: translateY(0); }
.back-top:hover { border-color: var(--accent); color: var(--accent); }
.back-top svg { width: 18px; height: 18px; fill: currentColor; }

/* ============ 北京时间卡片 ============ */
.clock-card .clock-body {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 6px 0;
}
.clock-card .clock-time {
  font-family: "SF Mono", Menlo, Consolas, monospace;
  font-size: 38px;
  font-weight: 700;
  letter-spacing: 3px;
  color: var(--text-primary);
  line-height: 1.1;
}
.clock-card .clock-date {
  font-size: 16px;
  color: var(--text-muted);
  letter-spacing: 1px;
}