/* ═══════════════════════════════════════
   LAYOUT.CSS - 底部导航、视图切换、通用动画
   ═══════════════════════════════════════ */

/* 主容器 */
#main-view {
  flex: 1;
  overflow: hidden;
  position: relative;
}

/* 视图页面 */
.view-page {
  position: absolute;
  inset: 0;
  display: none;
  flex-direction: column;
  background: var(--bg);
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  padding: 20px;
  padding-bottom: 120px;
}

.view-page.active {
  display: flex;
  animation: viewIn 0.45s cubic-bezier(0.22, 1, 0.36, 1);
}

@keyframes viewIn {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 底部导航 - 灵感之海风格 */
#tab-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 64px;
  background: var(--bg);
  border-top: 1px solid var(--rule);
  display: flex;
  justify-content: space-around;
  align-items: center;
  z-index: 900;
  padding-bottom: env(safe-area-inset-bottom);
}

.tab-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-family: var(--font-title);
  font-size: 16px;
  font-weight: 400;
  color: var(--ink);
  opacity: 0.25;
  flex: 1;
  height: 100%;
  transition: opacity 0.25s;
  cursor: pointer;
  letter-spacing: 0.12em;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
}

.tab-item.active {
  opacity: 1;
}

/* Toast 提示 - 极简线稿风格 */
#toast {
  position: fixed;
  bottom: 80px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--bg);
  color: var(--ink);
  border: 1px solid var(--rule);
  padding: 10px 20px;
  font-size: 0.8rem;
  font-weight: 300;
  letter-spacing: 0.06em;
  z-index: 9999;
  display: none;
  white-space: nowrap;
  pointer-events: none;
}

#toast.show {
  display: block;
  animation: toastIn 0.2s ease;
}

@keyframes toastIn {
  from { opacity: 0; transform: translateX(-50%) translateY(8px); }
  to   { opacity: 1; transform: translateX(-50%) translateY(0); }
}