/* 移动端防横向溢出：装饰元素超出视口时禁止横滚 */

/* ===== 全局 UI 组件：搜索覆盖框 + 返回顶部 ===== */

/* --- 返回顶部按钮 --- */
.back-to-top {
  position: fixed;
  bottom: 32px;
  right: 32px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: rgba(37, 99, 235, 0.9);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.15);
  cursor: pointer;
  z-index: 9998;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
  transition: opacity 0.3s, visibility 0.3s, transform 0.3s, background 0.2s;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.25);
}
.back-to-top.visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}
.back-to-top:hover {
  background: rgba(37, 99, 235, 1);
  transform: translateY(-2px);
  box-shadow: 0 6px 28px rgba(37, 99, 235, 0.4);
}
.back-to-top svg {
  width: 22px;
  height: 22px;
  fill: none;
  stroke: #fff;
  stroke-width: 2.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

/* --- 全局搜索覆盖框 --- */
.search-trigger {
  position: fixed;
  top: 4px;
  right: 16px;
  z-index: 9999;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255, 255, 255, 0.12);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s, border-color 0.2s;
}
.search-trigger:hover {
  background: rgba(255, 255, 255, 0.15);
  border-color: rgba(255, 255, 255, 0.25);
}
.search-trigger svg {
  width: 16px;
  height: 16px;
  fill: none;
  stroke: rgba(255, 255, 255, 0.85);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}
.search-trigger .search-hint {
  position: absolute;
  right: 40px;
  top: 50%;
  transform: translateY(-50%);
  white-space: nowrap;
  font-size: 12px;
  color: rgba(255, 255, 255, 0.5);
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.2s;
}
.search-trigger:hover .search-hint {
  opacity: 1;
}

/* 搜索覆盖层 */
.search-overlay {
  position: fixed;
  inset: 0;
  z-index: 10000;
  background: rgba(10, 12, 20, 0.85);
  backdrop-filter: blur(12px);
  display: flex;
  flex-direction: column;
  align-items: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s, visibility 0.25s;
}
.search-overlay.active {
  opacity: 1;
  visibility: visible;
}

/* 搜索容器 */
.search-container {
  width: 90%;
  max-width: 720px;
  margin-top: 10vh;
}
.search-box {
  position: relative;
  width: 100%;
}
.search-input {
  width: 100%;
  height: 56px;
  padding: 0 56px 0 56px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.15);
  color: #fff;
  font-size: 18px;
  font-family: inherit;
  outline: none;
  transition: border-color 0.2s, background 0.2s;
  box-sizing: border-box;
}
.search-input::placeholder {
  color: rgba(255, 255, 255, 0.35);
}
.search-input:focus {
  border-color: rgba(37, 99, 235, 0.6);
  background: rgba(255, 255, 255, 0.1);
}
.search-icon-left {
  position: absolute;
  left: 18px;
  top: 50%;
  transform: translateY(-50%);
  width: 22px;
  height: 22px;
  fill: none;
  stroke: rgba(255, 255, 255, 0.4);
  stroke-width: 2;
  stroke-linecap: round;
  pointer-events: none;
}
.search-close {
  position: absolute;
  right: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 32px;
  height: 32px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.06);
  border: none;
  color: rgba(255, 255, 255, 0.6);
  cursor: pointer;
  font-size: 18px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s;
}
.search-close:hover {
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
}

/* 搜索结果 */
.search-results {
  width: 90%;
  max-width: 720px;
  margin-top: 12px;
  max-height: 60vh;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: rgba(255, 255, 255, 0.15) transparent;
}
.search-results::-webkit-scrollbar {
  width: 6px;
}
.search-results::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.12);
  border-radius: 3px;
}

/* 结果组标题 */
.search-group-title {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.4);
  padding: 12px 4px 6px;
  font-weight: 600;
  letter-spacing: 0.5px;
}

/* 单条结果 */
.search-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 16px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
  cursor: pointer;
  margin-bottom: 6px;
  transition: background 0.15s, border-color 0.15s, transform 0.1s;
  text-decoration: none;
}
.search-item:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateX(4px);
}
.search-item-tag {
  flex-shrink: 0;
  padding: 3px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
  color: #fff;
  white-space: nowrap;
}
.search-item-body {
  flex: 1;
  min-width: 0;
}
.search-item-name {
  font-size: 15px;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.92);
  margin-bottom: 3px;
  line-height: 1.4;
}
.search-item-desc {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
  line-height: 1.5;
  overflow: hidden;
  text-overflow: ellipsis;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
}

/* 空状态 */
.search-empty {
  text-align: center;
  padding: 48px 20px;
  color: rgba(255, 255, 255, 0.35);
  font-size: 15px;
}
.search-empty .hint {
  margin-top: 8px;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.2);
}

/* 搜索统计 */
.search-stats {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.3);
  padding: 8px 4px;
}

/* 快捷键提示 */
.search-shortcut {
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 11px;
  color: rgba(255, 255, 255, 0.25);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 4px;
  padding: 2px 6px;
  pointer-events: none;
}

/* 移动端适配 */
@media (max-width: 640px) {
  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 42px;
    height: 42px;
  }
  .search-trigger {
    width: 30px;
    height: 30px;
    top: 5px;
    right: 8px;
  }
  .search-trigger svg {
    width: 15px;
    height: 15px;
  }
  .search-trigger .search-hint {
    display: none;
  }
  .search-container {
    width: 94%;
    margin-top: 6vh;
  }
  .search-input {
    height: 48px;
    font-size: 16px;
  }
  .search-results {
    width: 94%;
    max-height: 65vh;
  }
  .search-item {
    padding: 12px 14px;
  }
  .search-shortcut {
    display: none;
  }
}

/* 中屏：学科栏 48px（seewo 1440+），按钮 36px 居中 6~42 */
@media (min-width: 1440px) {
  .search-trigger {
    width: 36px;
    height: 36px;
    top: 6px;
    right: 18px;
  }
  .search-trigger svg {
    width: 18px;
    height: 18px;
  }
  .search-trigger .search-hint {
    right: 44px;
  }
}

/* 大屏：学科栏 52px（seewo 1920+），按钮 40px 居中 6~46 */
@media (min-width: 1920px) {
  .search-trigger {
    width: 40px;
    height: 40px;
    top: 6px;
    right: 22px;
  }
  .search-trigger svg {
    width: 20px;
    height: 20px;
  }
  .search-trigger .search-hint {
    right: 48px;
    font-size: 13px;
  }
}

/* 希沃大屏适配：学科栏 58px（2560+）/68px（3840+），按钮 44px 居中 7~51 */
@media (min-width: 2560px) {
  .back-to-top {
    width: 64px;
    height: 64px;
    bottom: 48px;
    right: 48px;
  }
  .back-to-top svg {
    width: 30px;
    height: 30px;
  }
  .search-trigger {
    width: 44px;
    height: 44px;
    top: 7px;
    right: 28px;
  }
  .search-trigger svg {
    width: 22px;
    height: 22px;
  }
  .search-trigger .search-hint {
    right: 52px;
    font-size: 15px;
  }
}

/* ============================================================
   第一性问答 Agent（搜索 overlay 内嵌模式）
   ============================================================ */

/* 模式切换 */
.mode-switch {
  display: flex;
  gap: 4px;
  padding: 3px;
  margin-top: 10px;
  background: rgba(255, 255, 255, 0.05);
  border-radius: 10px;
  border: 1px solid rgba(255, 255, 255, 0.08);
}
.mode-btn {
  flex: 1;
  padding: 7px 12px;
  border: none;
  border-radius: 8px;
  background: transparent;
  color: rgba(255, 255, 255, 0.45);
  font-size: 13px;
  font-family: inherit;
  cursor: pointer;
  transition: all 0.15s;
  white-space: nowrap;
}
.mode-btn:hover {
  color: rgba(255, 255, 255, 0.7);
}
.mode-btn.active {
  background: rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.95);
  font-weight: 600;
}

/* agent 模式下 results 更高 */
.search-overlay.agent-mode .search-results {
  max-height: 65vh;
}

/* ---- 欢迎屏 ---- */
.fp-welcome-hero {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 4px 4px 0;
}
.fp-avatar-yuan {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: linear-gradient(135deg, #2563EB, #7C3AED);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  font-weight: 700;
  color: #fff;
}
.fp-welcome-title {
  font-size: 16px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.92);
  margin-bottom: 4px;
}
.fp-welcome-title .hl {
  background: linear-gradient(135deg, #60A5FA, #A78BFA);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.fp-welcome-sub {
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.5);
  line-height: 1.6;
}

.fp-welcome-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 14px;
}
.fp-welcome-card {
  padding: 12px 14px;
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.07);
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s;
}
.fp-welcome-card:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.15);
}
.fp-welcome-top {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 5px;
}
.fp-welcome-top .d {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  flex-shrink: 0;
}
.fp-welcome-name {
  font-size: 13px;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.88);
}
.fp-welcome-tag {
  font-size: 10px;
  color: #FBBF24;
  background: rgba(251, 191, 36, 0.12);
  padding: 1px 6px;
  border-radius: 4px;
  margin-left: auto;
}
.fp-welcome-desc {
  font-size: 11.5px;
  color: rgba(255, 255, 255, 0.45);
  line-height: 1.5;
}

.fp-suggest-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 14px;
}
.fp-suggest-chip {
  padding: 6px 12px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.65);
  cursor: pointer;
  transition: all 0.15s;
}
.fp-suggest-chip:hover {
  background: rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.9);
  border-color: rgba(255, 255, 255, 0.2);
}

/* ---- 用户问题 ---- */
.fp-user-q {
  padding: 8px 14px;
  margin-bottom: 10px;
  background: rgba(37, 99, 235, 0.12);
  border-left: 3px solid #2563EB;
  border-radius: 0 8px 8px 0;
  font-size: 13.5px;
  color: rgba(255, 255, 255, 0.8);
}

/* ---- thinking 动画 ---- */
.fp-thinking {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 16px 4px;
}
.fp-thinking .t-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.4);
  animation: fp-bounce 1.2s infinite;
}
.fp-thinking .t-dot:nth-child(2) { animation-delay: 0.15s; }
.fp-thinking .t-dot:nth-child(3) { animation-delay: 0.3s; }
.fp-thinking .t-text {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.45);
  margin-left: 6px;
}
@keyframes fp-bounce {
  0%, 60%, 100% { opacity: 0.3; transform: scale(0.8); }
  30% { opacity: 1; transform: scale(1.2); }
}

/* ---- agent 说 ---- */
.fp-agent-say {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.7;
  padding: 0 2px 12px;
}
.fp-agent-say b {
  color: rgba(255, 255, 255, 0.95);
}

/* ---- 拆解卡 ---- */
.fp-card {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 14px;
  overflow: hidden;
}
.fp-card-head {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 12px 16px;
  background: rgba(255, 255, 255, 0.03);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}
.fp-card-head .d {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}
.fp-card-title {
  font-size: 14.5px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.92);
}
.fp-deep-tag {
  font-size: 10px;
  color: #FBBF24;
  background: rgba(251, 191, 36, 0.12);
  padding: 2px 7px;
  border-radius: 4px;
}
.fp-card-meta {
  margin-left: auto;
  font-size: 11px;
  color: rgba(255, 255, 255, 0.35);
  white-space: nowrap;
}
.fp-card-body {
  padding: 14px 16px;
}

/* ---- 步骤 ---- */
.fp-step {
  display: flex;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}
.fp-step:last-child {
  border-bottom: none;
}
.fp-step-num {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.6);
}
.fp-step-content {
  flex: 1;
  min-width: 0;
}
.fp-step-tag {
  font-size: 13px;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.75);
  margin-bottom: 5px;
}
.fp-step-text {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.55);
  line-height: 1.7;
}
.fp-step-title {
  font-size: 13px;
  font-weight: 600;
  color: rgba(255, 255, 255, 0.7);
}

/* ---- 符号 chips ---- */
.fp-sym-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}
.fp-sym-chip {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 4px 10px;
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.08);
  font-size: 12px;
  color: rgba(255, 255, 255, 0.6);
}
.fp-sym-chip .s {
  font-weight: 700;
  color: rgba(255, 255, 255, 0.85);
}

/* ---- 公式块 ---- */
.fp-formula-block {
  background: rgba(255, 255, 255, 0.06);
  border-radius: 10px;
  padding: 14px 16px;
  text-align: center;
}
.fp-formula-block .f {
  font-size: 20px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.9);
  font-family: 'Cambria Math', 'STIX Two Math', serif;
}
.fp-formula-block .fc {
  margin-top: 6px;
  font-size: 12px;
  color: rgba(255, 255, 255, 0.4);
}

/* ---- 反事实 ---- */
.fp-reverse-block {
  background: rgba(239, 68, 68, 0.08);
  border: 1px solid rgba(239, 68, 68, 0.15);
  border-radius: 10px;
  padding: 12px 14px;
}
.fp-reverse-block .rt {
  font-size: 12px;
  font-weight: 600;
  color: #FCA5A5;
  margin-bottom: 5px;
}
.fp-reverse-block .rd {
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.55);
  line-height: 1.7;
}

/* ---- 相关定律 chips ---- */
.fp-rel-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.fp-rel-chip {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 11px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.7);
  cursor: pointer;
  transition: all 0.15s;
}
.fp-rel-chip:hover {
  background: rgba(255, 255, 255, 0.12);
  color: rgba(255, 255, 255, 0.9);
}
.fp-rel-chip .d {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  flex-shrink: 0;
}

/* ---- 文章链接 ---- */
.fp-article-link {
  display: block;
  margin-top: 14px;
  padding: 10px 14px;
  border-radius: 10px;
  background: rgba(37, 99, 235, 0.12);
  border: 1px solid rgba(37, 99, 235, 0.2);
  font-size: 13px;
  color: #93C5FD;
  text-decoration: none;
  text-align: center;
  transition: background 0.15s;
}
.fp-article-link:hover {
  background: rgba(37, 99, 235, 0.2);
}

/* ---- hook ---- */
.fp-hook-line {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-top: 12px;
  padding: 10px 14px;
  border-radius: 10px;
  background: rgba(168, 85, 247, 0.08);
  border: 1px solid rgba(168, 85, 247, 0.15);
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.55);
  line-height: 1.7;
}
.fp-hook-line .ht {
  flex-shrink: 0;
  font-weight: 600;
  color: #C4B5FD;
}

/* ---- 追问 chips ---- */
.fp-chips-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
}
.fp-ask-chip {
  padding: 6px 12px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 12.5px;
  color: rgba(255, 255, 255, 0.65);
  cursor: pointer;
  transition: all 0.15s;
}
.fp-ask-chip:hover {
  background: rgba(124, 58, 237, 0.15);
  color: rgba(255, 255, 255, 0.9);
  border-color: rgba(124, 58, 237, 0.3);
}

/* ---- 移动端 ---- */
@media (max-width: 640px) {
  .mode-btn {
    font-size: 12px;
    padding: 6px 8px;
  }
  .fp-welcome-grid {
    grid-template-columns: 1fr;
  }
  .fp-card-meta {
    display: none;
  }
  .fp-formula-block .f {
    font-size: 17px;
  }
}