/* ============================================================
   智能中英词典 · 视觉系统
   浅色 / 深色双主题 · 渐变 + 玻璃拟态 · 动效
   ============================================================ */

:root {
  --bg-1: #eef1ff;
  --bg-2: #f7f8fd;
  --bg-3: #fdf7ee;
  --text: #1e2340;
  --text-sub: #6a7194;
  --text-faint: #9aa1c0;
  --card-bg: rgba(255, 255, 255, 0.86);
  --card-border: rgba(120, 130, 200, 0.16);
  --card-shadow: 0 12px 40px rgba(90, 100, 200, 0.10), 0 2px 8px rgba(90, 100, 200, 0.06);
  --input-bg: rgba(255, 255, 255, 0.92);
  --accent: #5b63f5;
  --accent-grad: linear-gradient(135deg, #6d7bf8 0%, #8b7cf6 100%);
  --hover-bg: rgba(91, 99, 245, 0.06);
  --divider: rgba(120, 130, 200, 0.14);
  --chip-bg: rgba(255, 255, 255, 0.8);
  --warn: #d97706;
  --ok: #3ecf8e;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg-1: #12152b;
    --bg-2: #171a33;
    --bg-3: #1d1a2e;
    --text: #e8ebf8;
    --text-sub: #9aa1c4;
    --text-faint: #6d7398;
    --card-bg: rgba(28, 32, 58, 0.88);
    --card-border: rgba(130, 140, 220, 0.18);
    --card-shadow: 0 12px 40px rgba(0, 0, 0, 0.35), 0 2px 8px rgba(0, 0, 0, 0.25);
    --input-bg: rgba(24, 27, 48, 0.95);
    --accent: #7b83ff;
    --accent-2: #9d8ffb;
    --accent-grad: linear-gradient(135deg, #6d7bf8 0%, #9d8ffb 100%);
    --hover-bg: rgba(123, 131, 255, 0.10);
    --divider: rgba(130, 140, 220, 0.16);
    --chip-bg: rgba(28, 32, 58, 0.9);
  }
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: linear-gradient(160deg, var(--bg-1) 0%, var(--bg-2) 45%, var(--bg-3) 100%);
  background-attachment: fixed;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background 0.3s ease, color 0.3s ease;
}

.hidden { display: none !important; }

::selection { background: rgba(109, 123, 248, 0.30); }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ============================================================
   顶栏
   ============================================================ */

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  background: color-mix(in srgb, var(--bg-2) 72%, transparent);
  backdrop-filter: blur(14px) saturate(1.4);
  -webkit-backdrop-filter: blur(14px) saturate(1.4);
  border-bottom: 1px solid var(--divider);
}

.brand { display: flex; align-items: center; gap: 10px; }

.brand-logo {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  font-size: 17px;
  border-radius: 11px;
  background: var(--accent-grad);
  box-shadow: 0 4px 14px rgba(91, 99, 245, 0.35);
}

.brand-name { font-size: 17px; font-weight: 700; letter-spacing: 0.5px; }

.brand-en {
  font-size: 10px;
  letter-spacing: 2.5px;
  color: var(--text-faint);
  font-weight: 600;
  padding-top: 2px;
}

.badge-stack {
  font-size: 11px;
  font-weight: 600;
  color: var(--accent);
  background: rgba(109, 123, 248, 0.10);
  border: 1px solid rgba(109, 123, 248, 0.25);
  border-radius: 99px;
  padding: 4px 12px;
}

/* ============================================================
   主体 / 搜索区
   ============================================================ */

main {
  flex: 1;
  width: 100%;
  max-width: 700px;
  margin: 0 auto;
  padding: 44px 20px 40px;
}

.hero { text-align: center; margin-bottom: 30px; }

.hero-title {
  font-size: 30px;
  font-weight: 800;
  letter-spacing: 1px;
  line-height: 1.35;
}

.grad-text {
  background: var(--accent-grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}

.hero-sub {
  margin-top: 8px;
  font-size: 14px;
  color: var(--text-sub);
}

.search-form {
  position: relative;
  /* 提升层级：结果卡片带 backdrop-filter/transform，会形成 z-index:auto 的层叠上下文并按 DOM 顺序绘制在搜索区之上，
     导致打开自动补全下拉时其底部圆角与边框被下方卡片遮挡；正 z-index 使整个搜索区（含下拉浮层）始终绘制在卡片之上 */
  z-index: 1;
  display: flex;
  gap: 10px;
  margin-top: 26px;
  padding: 8px;
  border-radius: 22px;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  box-shadow: var(--card-shadow);
  backdrop-filter: blur(10px);
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.search-form:focus-within {
  border-color: rgba(109, 123, 248, 0.55);
  box-shadow: 0 0 0 4px rgba(109, 123, 248, 0.14), var(--card-shadow);
}

#searchInput {
  flex: 1;
  min-width: 0;
  padding: 12px 16px;
  font-size: 17px;
  border: none;
  outline: none;
  background: transparent;
  color: var(--text);
}

#searchInput::placeholder { color: var(--text-faint); }

.search-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-width: 96px;
  padding: 12px 22px;
  font-size: 16px;
  font-weight: 600;
  border: none;
  border-radius: 16px;
  color: #fff;
  background: var(--accent-grad);
  cursor: pointer;
  box-shadow: 0 6px 18px rgba(91, 99, 245, 0.35);
  transition: transform 0.12s ease, box-shadow 0.2s ease, opacity 0.2s ease;
}

.search-btn:hover { transform: translateY(-1px); box-shadow: 0 8px 22px rgba(91, 99, 245, 0.45); }
.search-btn:active { transform: translateY(0); }
.search-btn:disabled { opacity: 0.65; cursor: default; transform: none; }

.btn-spinner {
  display: none;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, 0.35);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

.search-btn.loading .btn-spinner { display: block; }
.search-btn.loading .btn-label { display: none; }

.semantic-btn {
  flex: none;
  height: 52px;
  padding: 0 18px;
  border: 1.5px solid rgba(109, 123, 248, 0.55);
  border-radius: 16px;
  background: var(--chip-bg);
  color: var(--accent);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.15s ease;
}

.semantic-btn:hover:not(:disabled) {
  transform: translateY(-1px);
  background: rgba(109, 123, 248, 0.12);
  box-shadow: 0 6px 18px rgba(91, 99, 245, 0.25);
}

.semantic-btn:disabled { opacity: 0.65; cursor: default; }

@keyframes spin { to { transform: rotate(360deg); } }

/* 自动补全下拉 */
.suggest {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  right: 0;
  z-index: 60;
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 16px;
  box-shadow: 0 18px 50px rgba(60, 70, 160, 0.18);
  backdrop-filter: blur(16px);
  overflow: hidden;
  text-align: left;
}

.suggest-item {
  padding: 11px 18px;
  font-size: 15px;
  cursor: pointer;
  display: flex;
  align-items: baseline;
  gap: 10px;
  transition: background 0.12s ease;
}

.suggest-item:hover { background: var(--hover-bg); }
.suggest-item.active { background: var(--hover-bg); }

.suggest-item mark {
  background: transparent;
  color: var(--accent);
  font-weight: 700;
}

.suggest-word { font-weight: 600; }

.suggest-sub {
  font-size: 12px;
  color: var(--text-faint);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  flex: 1;
}

/* 快捷词 */
.chips {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin-top: 16px;
}

.chip {
  border: 1px solid var(--card-border);
  background: var(--chip-bg);
  color: var(--text-sub);
  font-size: 13px;
  padding: 6px 14px;
  border-radius: 99px;
  cursor: pointer;
  transition: all 0.15s ease;
}

.chip:hover {
  color: var(--accent);
  border-color: rgba(109, 123, 248, 0.5);
  transform: translateY(-1px);
}

.hint {
  margin-top: 14px;
  font-size: 13px;
  color: var(--text-faint);
  min-height: 18px;
}

.hint.error { color: #ef6a6a; font-weight: 500; }
.hint.ok { color: var(--ok); font-weight: 500; }

.mode-hint {
  margin-top: 10px;
  font-size: 12px;
  color: var(--warn);
  font-weight: 600;
}

/* ============================================================
   结果卡片
   ============================================================ */

.result { margin-top: 8px; }

.card {
  background: var(--card-bg);
  border: 1px solid var(--card-border);
  border-radius: 20px;
  padding: 22px 24px;
  margin-bottom: 16px;
  box-shadow: var(--card-shadow);
  backdrop-filter: blur(10px);
  animation: fadeUp 0.4s ease forwards;
  opacity: 0;
}

@keyframes fadeUp {
  to { opacity: 1; transform: translateY(0); }
}

/* 单词卡 */
.word-card { text-align: center; padding: 34px 24px 26px; }

.word-head { display: flex; align-items: center; justify-content: space-between; gap: 16px; flex-wrap: wrap; }

.word-left { display: flex; flex-direction: column; align-items: flex-start; gap: 6px; }

.word-phonetic {
  font-size: 14px;
  color: var(--text-sub);
  letter-spacing: 0.5px;
  font-family: ui-monospace, "SF Mono", Consolas, monospace;
}

.word-spelling {
  font-family: Georgia, "Times New Roman", "Songti SC", serif;
  font-size: 44px;
  font-weight: 700;
  letter-spacing: 1.5px;
  line-height: 1.2;
  background: var(--accent-grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  text-shadow: 0 10px 30px rgba(109, 123, 248, 0.25);
}

.speak-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid var(--card-border);
  background: var(--chip-bg);
  color: var(--text-sub);
  font-size: 13px;
  padding: 8px 14px;
  border-radius: 99px;
  cursor: pointer;
  transition: all 0.15s ease;
}

.speak-btn:hover {
  color: var(--accent);
  border-color: rgba(109, 123, 248, 0.5);
  transform: translateY(-1px);
}

/* 词条标签 */
.word-tags {
  margin-top: 18px;
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
}

.tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 500;
  color: var(--accent);
  background: rgba(109, 123, 248, 0.10);
  border: 1px solid rgba(109, 123, 248, 0.22);
  border-radius: 99px;
  padding: 3px 12px;
}

.tag-stars { color: #f5a623; background: rgba(245, 166, 35, 0.10); border-color: rgba(245, 166, 35, 0.30); }
.tag-oxford { color: #10b981; background: rgba(16, 185, 129, 0.10); border-color: rgba(16, 185, 129, 0.28); }
.tag-exam { color: #db2777; background: rgba(236, 72, 153, 0.10); border-color: rgba(236, 72, 153, 0.26); }
.tag-freq { color: #0284c7; background: rgba(14, 165, 233, 0.10); border-color: rgba(14, 165, 233, 0.28); }
.tag-dist { color: #7c3aed; background: rgba(124, 58, 237, 0.10); border-color: rgba(124, 58, 237, 0.28); }

/* 区块标题 */
.card-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 14px;
}

.title-ico { font-size: 15px; }

/* 列表项 */
.item-list { list-style: none; }

.item {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 11px 12px;
  border-radius: 12px;
  font-size: 15.5px;
  line-height: 1.7;
  word-break: break-word;
  transition: background 0.15s ease;
}

.item:hover { background: var(--hover-bg); }

.item + .item { border-top: 1px solid var(--divider); }

.item .dot {
  flex: none;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-top: 9px;
  background: var(--accent-grad);
  box-shadow: 0 0 8px rgba(109, 123, 248, 0.5);
}

.item .dot-en {
  background: linear-gradient(135deg, #4caf50, #2e7d32);
  box-shadow: 0 0 8px rgba(76, 175, 80, 0.4);
}

/* 词形变化 */
.exchange-wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.exchange-item {
  flex: 1 1 150px;
  padding: 10px 14px;
  border: 1px solid var(--card-border);
  border-radius: 12px;
  background: var(--chip-bg);
}

.exchange-label {
  font-size: 11px;
  font-weight: 700;
  color: var(--text-faint);
  letter-spacing: 1px;
  margin-bottom: 4px;
}

.exchange-value {
  font-size: 14.5px;
  color: var(--text);
  word-break: break-all;
}

/* 空状态 */
.empty {
  text-align: center;
  padding: 48px 0 30px;
  color: var(--text-sub);
  animation: fadeUp 0.4s ease forwards;
  opacity: 0;
}

.empty-emoji { font-size: 46px; margin-bottom: 12px; }
.empty p { font-size: 14px; }

/* 分页 */
.pager {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  margin-top: 4px;
}

.page-btn {
  padding: 9px 20px;
  border: 1px solid var(--card-border);
  border-radius: 99px;
  background: var(--chip-bg);
  color: var(--text-sub);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.15s ease;
}

.page-btn:hover:not(:disabled) {
  color: var(--accent);
  border-color: rgba(109, 123, 248, 0.5);
  transform: translateY(-1px);
}

.page-btn:disabled { opacity: 0.4; cursor: default; }

.page-info { font-size: 13px; color: var(--text-faint); }

/* ============================================================
   页脚 / 响应式
   ============================================================ */

.footer {
  text-align: center;
  padding: 20px;
  font-size: 12px;
  color: var(--text-faint);
}

@media (max-width: 560px) {
  .topbar { padding: 12px 16px; }
  main { padding: 28px 14px 32px; }
  .hero-title { font-size: 25px; }
  .hero-sub { font-size: 13px; }
  .search-form { flex-direction: column; }
  .search-btn { min-width: 100%; }
  .semantic-btn { min-width: 100%; }
  .word-spelling { font-size: 36px; }
  .card { padding: 18px 16px; }
  .brand-en { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}