/* 工程英语学习 — 商务工程深蓝灰配色（方案A）
   高对比度，适配工地户外强光手机屏幕 */

:root{
  --sb-w: 250px;
  --sb-w-m: 78px;

  /* 侧边栏（明暗模式统一保持深蓝灰，工程商务感） */
  --nav-bg: #0B1F33;
  --nav-bg-2: #102A44;
  --nav-line: #1E3E5C;
  --nav-text: #DCE9F5;
  --nav-text-dim: #8FA9C1;
  --nav-active: #12405F;

  /* 内容区 —— 亮色（强光可读） */
  --bg: #E9EEF3;
  --surface: #FFFFFF;
  --surface-2: #F3F7FA;
  --text: #0A1B2A;
  --text-2: #23415A;
  --muted: #4E6A82;
  --border: #C4D3E0;
  --border-2: #DBE5EE;

  --accent: #C2620E;        /* 工程橙，用于强调按钮 */
  --accent-soft: #FDF0E2;
  --brand: #0E3557;
  --brand-soft: #E4EDF5;
  --brand-2: #C2620E;        /* 嵌套子分组左边线强调色（工程橙） */
  --ok: #14663C;
  --ok-soft: #E2F2E8;
  --warn: #8A5B00;

  --radius: 12px;
  --shadow: 0 1px 2px rgba(11,31,51,.10), 0 6px 18px rgba(11,31,51,.06);
}

html[data-theme="dark"]{
  --bg: #081420;
  --surface: #0F2131;
  --surface-2: #14293B;
  --text: #EAF2F9;
  --text-2: #C2D6E6;
  --muted: #93AFC6;
  --border: #23425D;
  --border-2: #1B3549;

  --accent: #F0A24A;
  --accent-soft: #2A2013;
  --brand: #7FB6E4;
  --brand-soft: #14293B;
  --brand-2: #F0A24A;
  --ok: #6FD79E;
  --ok-soft: #102A20;
  --warn: #E2B457;
  --shadow: 0 1px 2px rgba(0,0,0,.4);
}

*{ box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

html{ font-size: 100%; }

body{
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC",
               "PingFang SC", "Microsoft YaHei", Roboto, Arial, sans-serif;
  font-size: 1rem;
  line-height: 1.5;
  -webkit-text-size-adjust: 100%;
  overscroll-behavior-y: none;
}

/* ---------------- 侧边栏（手机、电脑同一套，手机仅缩窄） ---------------- */
.sidebar{
  position: fixed;
  top: 0; left: 0; bottom: 0;
  width: var(--sb-w);
  background: linear-gradient(180deg, var(--nav-bg) 0%, var(--nav-bg-2) 100%);
  border-right: 1px solid var(--nav-line);
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  overflow-x: hidden;
  z-index: 20;
  padding-bottom: env(safe-area-inset-bottom);
}
.brand{
  display: flex; align-items: center; gap: .5rem;
  padding: 1rem .85rem .85rem;
  border-bottom: 1px solid var(--nav-line);
  position: sticky; top: 0;
  background: var(--nav-bg);
  z-index: 2;
}
.brand-logo{ font-size: 1.5rem; line-height: 1; }
.brand-txt{ min-width: 0; }
.brand-title{ color: #fff; font-weight: 800; font-size: 1.02rem; letter-spacing: .5px; white-space: nowrap; }
.brand-sub{ color: var(--nav-text-dim); font-size: .7rem; white-space: nowrap; }

.nav{ padding: .5rem .5rem 1rem; display: flex; flex-direction: column; gap: .25rem; }
.nav-label{
  color: var(--nav-text-dim); font-size: .68rem; font-weight: 700;
  padding: .55rem .5rem .3rem; letter-spacing: .12em;
}
.nav-item{
  display: flex; align-items: center; gap: .6rem;
  padding: .62rem .6rem;
  border-radius: 10px;
  color: var(--nav-text);
  text-decoration: none;
  border: 1px solid transparent;
  font-size: .93rem;
}
.nav-item .ico{ font-size: 1.15rem; line-height: 1; flex: 0 0 auto; }
.nav-item .lbl{ white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.nav-item .cnt{
  margin-left: auto; font-size: .68rem; color: var(--nav-text-dim);
  background: rgba(255,255,255,.07); padding: .08rem .34rem; border-radius: 999px;
}
.nav-item:active{ background: var(--nav-active); }
.nav-item.active{
  background: var(--nav-active);
  border-color: #2C6690;
  color: #fff; font-weight: 700;
  box-shadow: inset 3px 0 0 var(--accent);
}
.nav-foot{
  margin-top: auto; padding: .7rem .8rem 1rem;
  color: var(--nav-text-dim); font-size: .68rem; border-top: 1px solid var(--nav-line);
}

/* ---------------- 主内容区 ---------------- */
.main{
  margin-left: var(--sb-w);
  min-height: 100vh;
  padding: 1rem 1.1rem 3rem;
  max-width: 1180px;
}
.page-head{
  display: flex; flex-wrap: wrap; align-items: flex-end; gap: .5rem 1rem;
  padding: .35rem 0 .8rem;
  border-bottom: 2px solid var(--border);
  margin-bottom: 1rem;
}
.page-head h1{ margin: 0; font-size: 1.32rem; letter-spacing: .4px; }
.page-head p{ margin: .2rem 0 0; color: var(--muted); font-size: .84rem; max-width: 62ch; }
.page-stat{
  margin-left: auto; font-size: .76rem; color: var(--text-2);
  background: var(--brand-soft); border: 1px solid var(--border);
  padding: .28rem .6rem; border-radius: 999px; white-space: nowrap; font-weight: 600;
}

/* 工具条 */
.toolbar{
  display: flex; flex-wrap: wrap; gap: .5rem;
  margin-bottom: 1rem; align-items: center;
}
.search{
  flex: 1 1 240px; min-width: 0;
  display: flex; align-items: center; gap: .45rem;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 10px; padding: .45rem .6rem;
}
.search input{
  border: 0; outline: 0; background: transparent; color: var(--text);
  font-size: .95rem; width: 100%; font-family: inherit;
}
.chips{ display: flex; gap: .35rem; flex-wrap: wrap; }
.chip{
  background: var(--surface); border: 1px solid var(--border); color: var(--text-2);
  border-radius: 999px; padding: .32rem .62rem; font-size: .78rem; cursor: pointer;
  font-family: inherit; font-weight: 600;
}
.chip.on{ background: var(--brand); border-color: var(--brand); color: #fff; }
html[data-theme="dark"] .chip.on{ color: #06131f; }

/* ---------------- 卡片 ---------------- */
.card{
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-bottom: 1rem;
  overflow: hidden;
}
.card-head{
  padding: .7rem .85rem;
  background: var(--surface-2);
  border-bottom: 1px solid var(--border-2);
  border-left: 4px solid var(--brand);
}
.card-title{
  display: flex; align-items: center; gap: .45rem;
  font-weight: 800; font-size: 1.02rem; color: var(--text);
}
.card-title .n{
  margin-left: auto; font-size: .7rem; font-weight: 700; color: var(--muted);
  background: var(--bg); border: 1px solid var(--border-2);
  padding: .05rem .4rem; border-radius: 999px;
}
.card-desc{ margin: .25rem 0 0; font-size: .8rem; color: var(--muted); }
.card-body{ padding: .35rem .55rem .55rem; }

/* 句子行 */
.row{
  display: flex; gap: .6rem; align-items: flex-start;
  padding: .6rem .35rem;
  border-bottom: 1px dashed var(--border-2);
}
.row:last-child{ border-bottom: 0; }
.row-txt{ flex: 1 1 auto; min-width: 0; }
.en{
  margin: 0; font-size: 1rem; font-weight: 650; color: var(--text);
  line-height: 1.45; word-break: break-word;
}
.zh{ margin: .15rem 0 0; font-size: .9rem; color: var(--text-2); }
.sw{ margin: .2rem 0 0; font-size: .78rem; color: var(--warn); font-weight: 600; }
.note{ margin: .2rem 0 0; font-size: .78rem; color: var(--muted); }
.row-btns{ flex: 0 0 auto; display: flex; flex-direction: column; gap: .3rem; }

/* 词条行 */
.row.term .en{ font-size: .98rem; }
.row.term .zh{ font-size: .95rem; font-weight: 600; color: var(--text); }

/* 嵌套大卡片（甲方会议口语 / 会议词汇）：一个大卡片内含多个子分组 */
.card-extra{ border-left: 4px solid var(--brand); }
.card-extra > .card-head{ border-left: 0; }
.sub{
  margin: .55rem .2rem .2rem;
  background: var(--surface-2);
  border: 1px solid var(--border-2);
  border-radius: var(--radius);
  overflow: hidden;
}
.sub-head{
  display: flex; align-items: center; gap: .4rem;
  padding: .5rem .7rem;
  font-weight: 800; font-size: .92rem; color: var(--text);
  background: var(--bg);
  border-bottom: 1px solid var(--border-2);
  border-left: 3px solid var(--brand-2);
}
.sub-head .n{
  margin-left: auto; font-size: .68rem; font-weight: 700; color: var(--muted);
  background: var(--surface); border: 1px solid var(--border-2);
  padding: .04rem .36rem; border-radius: 999px;
}
.sub-desc{ margin: 0; padding: .35rem .7rem 0; font-size: .78rem; color: var(--muted); }
.sub-body{ padding: .2rem .5rem .5rem; }
.sub-body .row{ padding: .55rem .35rem; }


/* 邮件项 */
.mail-item{ padding: .65rem .35rem; border-bottom: 1px dashed var(--border-2); }
.mail-item:last-child{ border-bottom: 0; }
.mail-top{ display: flex; flex-wrap: wrap; gap: .4rem; align-items: center; }
.mail-title{ font-weight: 800; font-size: .98rem; }
.mail-zh{ margin: .2rem 0 .4rem; font-size: .82rem; color: var(--muted); }
.mail-subject{
  font-size: .85rem; color: var(--text); background: var(--brand-soft);
  border: 1px solid var(--border); border-radius: 8px; padding: .35rem .5rem;
  margin-bottom: .4rem; word-break: break-word;
}
.mail-subject b{ color: var(--muted); font-weight: 700; }
pre.mail-body{
  margin: 0; padding: .6rem .7rem;
  background: var(--surface-2); border: 1px solid var(--border-2);
  border-radius: 8px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: .82rem; line-height: 1.55; color: var(--text);
  white-space: pre-wrap; word-break: break-word;
  max-height: 15rem; overflow: auto;
}
.mail-btns{ display: flex; flex-wrap: wrap; gap: .35rem; margin-top: .45rem; }

/* ---------------- 按钮 ---------------- */
.btn{
  font-family: inherit; font-size: .78rem; font-weight: 700;
  border-radius: 8px; border: 1px solid var(--border);
  background: var(--surface-2); color: var(--text);
  padding: .38rem .5rem; cursor: pointer; white-space: nowrap;
  display: inline-flex; align-items: center; gap: .25rem;
}
.btn:active{ transform: translateY(1px); }
.btn-copy{ background: var(--brand); border-color: var(--brand); color: #fff; }
html[data-theme="dark"] .btn-copy{ color: #061420; }
.btn-speak{ background: var(--ok-soft); border-color: var(--ok); color: var(--ok); }
.btn-speak.speaking{ background: var(--ok); border-color: var(--ok); color: #fff; animation: speakPulse 1.2s ease-in-out infinite; }
html[data-theme="dark"] .btn-speak.speaking{ color: #06120b; }
@keyframes speakPulse{ 0%,100%{ box-shadow: 0 0 0 0 rgba(20,102,60,.35); } 50%{ box-shadow: 0 0 0 5px rgba(20,102,60,0); } }
.btn-fav.on{ background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }
.btn-lg{ font-size: .88rem; padding: .5rem .8rem; }
.btn-accent{ background: var(--accent); border-color: var(--accent); color: #fff; }
html[data-theme="dark"] .btn-accent{ color: #1b1305; }
.btn-danger{ background: #FBE9E9; border-color: #D99; color: #9B1C1C; }
html[data-theme="dark"] .btn-danger{ background: #2C1517; border-color: #6B2B2B; color: #F3B0B0; }
.btn-row{ display: flex; flex-wrap: wrap; gap: .45rem; }

/* ---------------- 表单（速记本 / 设置） ---------------- */
.field{ margin-bottom: .55rem; }
.field label{ display: block; font-size: .78rem; font-weight: 700; color: var(--muted); margin-bottom: .22rem; }
.field input, .field textarea{
  width: 100%; font-family: inherit; font-size: .95rem;
  padding: .5rem .6rem; color: var(--text);
  background: var(--surface-2); border: 1px solid var(--border); border-radius: 8px;
  outline: none;
}
.field input:focus, .field textarea:focus{ border-color: var(--brand); }
.field textarea{ min-height: 4.5rem; resize: vertical; }

.set-row{
  display: flex; flex-wrap: wrap; gap: .6rem; align-items: center;
  padding: .6rem .35rem; border-bottom: 1px dashed var(--border-2);
}
.set-row:last-child{ border-bottom: 0; }
.set-label{ flex: 1 1 190px; }
.set-label b{ display: block; font-size: .94rem; }
.set-label span{ font-size: .78rem; color: var(--muted); }
.fs-demo{
  margin-top: .5rem; padding: .55rem .65rem; border-radius: 8px;
  background: var(--surface-2); border: 1px dashed var(--border);
  font-size: .95rem;
}
.kv{ display: flex; flex-wrap: wrap; gap: .4rem .9rem; font-size: .84rem; color: var(--text-2); }
.kv div b{ color: var(--text); }

.empty{
  padding: .8rem .5rem; color: var(--muted); font-size: .86rem;
}
.tag{
  display: inline-block; font-size: .7rem; font-weight: 700;
  background: var(--accent-soft); color: var(--accent);
  border: 1px solid var(--accent); border-radius: 999px;
  padding: .04rem .42rem; margin-right: .3rem;
}
.tag.src{ background: var(--brand-soft); color: var(--brand); border-color: var(--brand); }
.ts{ font-size: .72rem; color: var(--muted); }

/* ---------------- 复制成功提示 ---------------- */
.toast{
  position: fixed; left: 50%; bottom: 1.6rem; transform: translate(-50%, 1.2rem);
  background: #0B1F33; color: #fff; font-size: .9rem; font-weight: 700;
  padding: .6rem 1rem; border-radius: 999px;
  box-shadow: 0 8px 24px rgba(0,0,0,.35);
  opacity: 0; pointer-events: none; transition: all .18s ease;
  z-index: 99; border: 1px solid #2C6690; max-width: 86vw; text-align: center;
}
.toast.show{ opacity: 1; transform: translate(-50%, 0); }

/* ---------------- 手机端：侧边栏缩窄，不改底部导航 ---------------- */
@media (max-width: 760px){
  .sidebar{ width: var(--sb-w-m); }
  .main{ margin-left: var(--sb-w-m); padding: .75rem .7rem 3rem; }

  .brand{ flex-direction: column; gap: .1rem; padding: .6rem .3rem .55rem; text-align: center; }
  .brand-txt{ display: none; }
  .brand::after{
    content: "工程英语"; color: #fff; font-size: .62rem; font-weight: 800; letter-spacing: .5px;
  }
  .nav{ padding: .35rem .28rem 1rem; }
  .nav-label{ display: none; }
  .nav-item{
    flex-direction: column; gap: .12rem; padding: .5rem .1rem;
    text-align: center; border-radius: 9px;
  }
  .nav-item .ico{ font-size: 1.3rem; }
  .nav-item .lbl{
    font-size: .58rem; line-height: 1.15; white-space: normal;
    overflow: visible; text-overflow: clip; font-weight: 700;
  }
  .nav-item .cnt{ display: none; }
  .nav-item.active{ box-shadow: inset 0 -3px 0 var(--accent); }
  .nav-foot{ display: none; }

  .page-head h1{ font-size: 1.1rem; }
  .page-head p{ font-size: .78rem; }
  .page-stat{ margin-left: 0; }
  .row{ flex-direction: column; gap: .4rem; padding: .55rem .3rem; }
  .row-btns{ flex-direction: row; }
  .en{ font-size: .97rem; }
  .card-body{ padding: .3rem .4rem .5rem; }
  pre.mail-body{ font-size: .78rem; max-height: 13rem; }
}

@media (max-width: 360px){
  :root{ --sb-w-m: 66px; }
  .nav-item .lbl{ font-size: .54rem; }
}