:root {
  --bg: #f5f7fb;
  --panel: #ffffff;
  --ink: #1f2733;
  --muted: #6b7686;
  --line: #e6eaf1;
  --accent: #4f46e5;
  --accent-soft: #eef0ff;
  --ok: #16a34a;
  --shadow: 0 1px 3px rgba(20,30,50,.08), 0 6px 18px rgba(20,30,50,.06);
  --radius: 14px;
}
* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
}

/* App header (sticky wrapper: holds topbar + segments together) */
.app-header {
  position: sticky; top: 0; z-index: 30;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(160%) blur(10px);
  -webkit-backdrop-filter: saturate(160%) blur(10px);
  border-bottom: 1px solid var(--line);
}
.topbar {
  display: flex; flex-wrap: wrap; gap: 12px 20px;
  align-items: center; justify-content: space-between;
  padding: 14px clamp(14px, 4vw, 40px);
}
.brand h1 { font-size: clamp(17px, 2.4vw, 22px); margin: 0; letter-spacing: .3px; }
.brand .sub { margin: 2px 0 0; color: var(--muted); font-size: 13px; }
.controls { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.accent { display: inline-flex; background: var(--accent-soft); border-radius: 999px; padding: 3px; }
.accent button {
  border: 0; background: transparent; color: var(--muted);
  padding: 6px 14px; border-radius: 999px; cursor: pointer; font-size: 14px; font-weight: 600;
}
.accent button.active { background: var(--accent); color: #fff; }
.zh-toggle { display: inline-flex; align-items: center; gap: 6px; font-size: 14px; color: var(--ink); cursor: pointer; user-select: none; }
.zh-toggle input { width: 16px; height: 16px; accent-color: var(--accent); }
#search {
  border: 1px solid var(--line); background: #fff; border-radius: 999px;
  padding: 9px 16px; font-size: 14px; width: min(260px, 60vw); outline: none;
}
#search:focus { border-color: var(--accent); }
.progress { display: flex; align-items: center; gap: 8px; font-size: 12.5px; color: var(--muted); }
.progress .bar { width: 90px; height: 7px; background: var(--line); border-radius: 999px; overflow: hidden; }
.progress .bar span { display: block; height: 100%; width: 0; background: var(--ok); transition: width .25s; }
#cacheBtn {
  border: 1px solid var(--accent); color: var(--accent); background: var(--accent-soft);
  border-radius: 999px; padding: 8px 14px; font-size: 13.5px; font-weight: 600; cursor: pointer;
  display: inline-flex; align-items: center; gap: 6px;
}
#cacheBtn:hover { background: #e3e6ff; }
#cacheBtn:disabled { opacity: .65; cursor: default; }

/* Segments */
.segments {
  display: flex; gap: 8px; overflow-x: auto; padding: 10px clamp(14px,4vw,40px);
  scrollbar-width: thin;
}
.seg {
  flex: 0 0 auto; display: flex; align-items: center; gap: 8px;
  border: 1px solid var(--line); background: var(--panel); border-radius: 999px;
  padding: 7px 14px; cursor: pointer; font-size: 13.5px; white-space: nowrap; color: var(--ink);
}
.seg:hover { border-color: var(--accent); }
.seg .cnt { color: var(--muted); font-size: 12px; }
.seg .play { margin-left: 4px; color: var(--accent); font-size: 12px; border-left: 1px solid var(--line); padding-left: 8px; }

/* List */
main { padding: 4px clamp(14px,4vw,40px) 120px; max-width: 1100px; margin: 0 auto; }
.section { scroll-margin-top: 160px; margin-top: 22px; }
.section-head {
  display: flex; align-items: center; justify-content: space-between;
  margin: 8px 2px 12px;
}
.section-head h2 { font-size: 16px; margin: 0; }
.section-head .meta { color: var(--muted); font-size: 13px; }
.section-head .playseg {
  border: 1px solid var(--accent); color: var(--accent); background: #fff;
  border-radius: 999px; padding: 6px 14px; font-size: 13px; cursor: pointer; font-weight: 600;
}
.section-head .playseg:hover { background: var(--accent-soft); }
.grid {
  display: grid; gap: 12px;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
}

/* Card */
.card {
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 14px 16px; box-shadow: var(--shadow); position: relative; transition: border-color .15s, transform .15s;
}
.card.playing { border-color: var(--accent); box-shadow: 0 0 0 2px var(--accent-soft), var(--shadow); }
.card.done { background: linear-gradient(0deg, #f6fff8, #ffffff); }
.card .row1 { display: flex; align-items: baseline; gap: 10px; }
.card .word { font-size: 22px; font-weight: 700; letter-spacing: .3px; }
.card .ph { color: var(--muted); font-size: 13.5px; }
.card .zh { margin-top: 4px; color: #33404f; font-size: 15px; }
.card .ex { margin-top: 6px; color: var(--muted); font-size: 13px; line-height: 1.5; }
.card .actions { display: flex; gap: 8px; margin-top: 12px; align-items: center; }
.btn {
  border: 1px solid var(--line); background: #fff; border-radius: 10px;
  padding: 7px 12px; font-size: 13px; cursor: pointer; color: var(--ink);
  display: inline-flex; align-items: center; gap: 6px;
}
.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn:hover { filter: brightness(.98); }
.btn:active { transform: scale(.97); }
.card .check {
  margin-left: auto; font-size: 13px; color: var(--muted); cursor: pointer;
  border: 1px solid var(--line); border-radius: 10px; padding: 7px 11px; background: #fff;
}
.card.done .check { color: var(--ok); border-color: var(--ok); background: #f0fdf4; }

mark { background: #fff2a8; border-radius: 3px; padding: 0 1px; }

/* Player bar */
.player {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 40;
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px; padding: 12px clamp(14px,4vw,40px);
  background: var(--ink); color: #fff; box-shadow: 0 -6px 24px rgba(0,0,0,.18);
}
.player-info { display: flex; align-items: center; gap: 10px; font-size: 14px; min-width: 0; }
.player-info .dot { width: 9px; height: 9px; border-radius: 50%; background: #4ade80; animation: pulse 1s infinite; }
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:.3} }
.player-info span { white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.player-actions { display: flex; gap: 8px; flex: 0 0 auto; }
.player-actions button {
  border: 1px solid rgba(255,255,255,.3); background: rgba(255,255,255,.08); color: #fff;
  border-radius: 10px; padding: 8px 14px; cursor: pointer; font-size: 14px;
}
.player-actions button:hover { background: rgba(255,255,255,.16); }

.empty { text-align: center; color: var(--muted); padding: 60px 0; }

/* View tabs (全部单词 / 学习计划) */
.viewtabs { display: flex; gap: 8px; padding: 0 clamp(14px,4vw,40px) 10px; }
.viewtabs button {
  border: 1px solid var(--line); background: var(--panel); color: var(--muted);
  border-radius: 999px; padding: 7px 16px; font-size: 13.5px; cursor: pointer; font-weight: 600;
}
.viewtabs button.active { background: var(--accent); color: #fff; border-color: var(--accent); }

/* Plan view */
#planView { padding: 4px clamp(14px,4vw,40px) 120px; max-width: 1100px; margin: 0 auto; }
.plan-bar {
  display: flex; flex-direction: column; gap: 10px;
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 14px 16px; box-shadow: var(--shadow); margin-top: 14px;
}
.plan-set { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; font-size: 14px; color: var(--ink); }
.plan-set .lbl { color: var(--muted); font-weight: 600; }
.plan-set .sep { color: var(--line); }
.pd { border: 1px solid var(--line); background: #fff; border-radius: 999px; padding: 6px 14px; cursor: pointer; font-size: 14px; font-weight: 600; color: var(--ink); }
.pd.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.plan-input { border: 1px solid var(--line); border-radius: 10px; padding: 6px 10px; font-size: 14px; outline: none; }
.plan-input[type=number] { width: 86px; }
.plan-input[type=date] { width: auto; }
.plan-ov { font-size: 14px; color: var(--muted); }
.plan-ov b { color: var(--accent); }
.plan-days { display: flex; gap: 8px; overflow-x: auto; padding: 14px 0 4px; scrollbar-width: thin; }
.plan-days .day {
  flex: 0 0 auto; border: 1px solid var(--line); background: var(--panel); border-radius: 999px;
  padding: 7px 14px; cursor: pointer; font-size: 13px; white-space: nowrap; color: var(--ink);
}
.plan-days .day.today { border-color: var(--accent); color: var(--accent); }
.plan-days .day.cur { background: var(--accent); color: #fff; border-color: var(--accent); }
.plan-day-head { display: flex; align-items: center; justify-content: space-between; margin: 12px 2px; }
.plan-day-head h2 { font-size: 16px; margin: 0; }
@media (max-width: 560px) {
  .grid { grid-template-columns: 1fr; }
  #search { width: 100%; }
  .controls { width: 100%; }
}