/* ============================================================
   《人工智能与图像识别》课程网站
   设计系统：蜡笔盒八色系（与 17 套课件 PPT 同源）
   红 E63946 · 橙 F77F00 · 芒果黄 FCBF49 · 绿 06A77D
   天蓝 00B4D8 · 宝蓝 2E5EAA · 紫 8338EC · 玫红 EF476F
   签名母题：圆角卡片 + 超大数字水印 + 彩色贴纸标签
   ============================================================ */

:root {
  --red: #E63946;
  --orange: #F77F00;
  --yellow: #FCBF49;
  --green: #06A77D;
  --sky: #00B4D8;
  --blue: #2E5EAA;
  --purple: #8338EC;
  --pink: #EF476F;
  --ink: #2B2D42;
  --ink-soft: #5E6178;
  --paper: #FFFFFF;
  --cream: #F4F1EA;
  --red-l: #FDE8E8;
  --orange-l: #FEF0DF;
  --yellow-l: #FEF7DC;
  --green-l: #DFF3EC;
  --sky-l: #DFF4FB;
  --blue-l: #E4EBF7;
  --purple-l: #EFE6FB;
  --pink-l: #FCE5EC;
  --yellow-d: #C99700;
  --sky-d: #0077B6;
  --radius: 18px;
  --radius-sm: 12px;
  --shadow: 0 6px 24px rgba(43, 45, 66, 0.08);
  --shadow-lift: 0 10px 30px rgba(43, 45, 66, 0.14);
}

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

/* author 的 display:flex 等规则会压过 UA 的 [hidden]，这里强制恢复 */
[hidden] { display: none !important; }

html { scroll-behavior: smooth; }

body {
  font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", "Noto Sans SC", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
ul { list-style: none; }

.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }

/* ---------- 蜡笔盒条纹（品牌母题） ---------- */
.crayons { display: inline-flex; gap: 5px; align-items: center; }
.crayons i {
  display: block; width: 7px; height: 22px; border-radius: 4px;
}
.crayons i:nth-child(1) { background: var(--red); }
.crayons i:nth-child(2) { background: var(--orange); }
.crayons i:nth-child(3) { background: var(--yellow); }
.crayons i:nth-child(4) { background: var(--green); }
.crayons i:nth-child(5) { background: var(--sky); }
.crayons i:nth-child(6) { background: var(--blue); }
.crayons i:nth-child(7) { background: var(--purple); }
.crayons i:nth-child(8) { background: var(--pink); }
.crayons--big i { width: 14px; height: 44px; border-radius: 7px; }
.crayons--big { gap: 8px; }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  box-shadow: 0 2px 12px rgba(43, 45, 66, 0.06);
}
.site-header .inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 700; font-size: 17px; }
.brand small { display: block; font-size: 11px; font-weight: 400; color: var(--ink-soft); line-height: 1.2; }
.main-nav { display: flex; gap: 8px; }
.main-nav a {
  padding: 7px 16px; border-radius: 999px; font-size: 15px;
  color: var(--ink-soft); transition: all 0.18s ease;
}
.main-nav a:hover { background: var(--cream); color: var(--ink); }
.main-nav a.active { background: var(--ink); color: #fff; }
.nav-toggle {
  display: none; background: none; border: none; cursor: pointer;
  width: 40px; height: 40px; border-radius: 10px;
}
.nav-toggle span, .nav-toggle span::before, .nav-toggle span::after {
  display: block; width: 20px; height: 2.5px; border-radius: 2px;
  background: var(--ink); position: relative; transition: all 0.2s;
}
.nav-toggle span::before, .nav-toggle span::after { content: ""; position: absolute; }
.nav-toggle span::before { top: -7px; }
.nav-toggle span::after { top: 7px; }

/* ---------- 贴纸标签（签名母题） ---------- */
.sticker {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 4px 14px; border-radius: 999px;
  font-size: 14px; font-weight: 700; color: #fff;
  background: var(--cs, var(--c, var(--ink)));
  white-space: nowrap;
}
.sticker--soft {
  color: var(--cs, var(--c, var(--ink)));
  background: var(--cl, var(--cream));
}
.sticker--tilt { transform: rotate(-2deg); }
.sticker--tilt2 { transform: rotate(1.5deg); }

/* ---------- 首页 Hero ---------- */
.hero {
  margin-top: 28px;
  background: var(--ink);
  border-radius: 26px;
  padding: 56px 48px 52px;
  color: #fff;
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-lift);
}
.hero .crayons--big { margin-bottom: 26px; }
.hero h1 {
  font-size: clamp(30px, 5vw, 46px);
  line-height: 1.25; letter-spacing: 1px; margin-bottom: 12px;
}
.hero .sub {
  font-size: clamp(15px, 2vw, 18px); color: #C9CBD9; margin-bottom: 26px;
  max-width: 640px;
}
.hero .chips { display: flex; flex-wrap: wrap; gap: 10px; margin-bottom: 34px; }
.hero .chips span {
  font-size: 13px; padding: 5px 14px; border-radius: 999px;
  background: rgba(255, 255, 255, 0.12); color: #E8E9F0;
}
.hero .actions { display: flex; flex-wrap: wrap; gap: 14px; align-items: center; }
.hero .float-stickers { position: absolute; right: 40px; top: 40px; display: flex; flex-direction: column; gap: 12px; }
.hero .float-stickers .sticker { box-shadow: 0 4px 14px rgba(0,0,0,0.25); font-size: 13px; }
.hero .watermark {
  position: absolute; right: -30px; bottom: -60px;
  font-size: 260px; font-weight: 900; line-height: 1;
  color: rgba(255, 255, 255, 0.05); pointer-events: none; user-select: none;
}

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 11px 26px; border-radius: 999px;
  font-size: 15px; font-weight: 700;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  cursor: pointer; border: none;
}
.btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-lift); }
.btn--yellow { background: var(--yellow); color: var(--ink); }
.btn--white { background: #fff; color: var(--ink); }
.btn--ghost { background: transparent; color: #fff; box-shadow: inset 0 0 0 2px rgba(255,255,255,0.5); }
.btn--ink { background: var(--ink); color: #fff; }
.btn--c { background: var(--cs, var(--c, var(--ink))); color: #fff; }
.btn--soft { background: var(--cl, var(--cream)); color: var(--cs, var(--c, var(--ink))); }
.btn--sm { padding: 7px 16px; font-size: 13px; }

/* ---------- 区块通用 ---------- */
.section { padding: 56px 0 8px; }
.sec-head { display: flex; align-items: center; gap: 14px; flex-wrap: wrap; margin-bottom: 10px; }
.sec-head h2 { font-size: clamp(22px, 3vw, 28px); }
.sec-head .spacer { flex: 1; }
.sec-desc { color: var(--ink-soft); max-width: 760px; margin-bottom: 26px; font-size: 15px; }

/* ---------- 信息卡（首页） ---------- */
.info-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 16px; }
.info-card {
  border-radius: var(--radius); padding: 22px;
  background: var(--cl, var(--cream)); position: relative; overflow: hidden;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.info-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.info-card .tag {
  display: inline-block; font-size: 12px; font-weight: 700;
  color: var(--cs); background: rgba(255,255,255,0.75);
  padding: 3px 10px; border-radius: 999px; margin-bottom: 10px;
}
.info-card .big { font-size: 22px; font-weight: 800; line-height: 1.4; }
.info-card .note { font-size: 13px; color: var(--ink-soft); margin-top: 6px; }

/* 颜色工具类：--c 主色 / --cl 浅底 / --cs 强调色（黄、天蓝在浅底上换深色保证对比） */
.c-red    { --c: var(--red);    --cl: var(--red-l);    --cs: var(--red); }
.c-orange { --c: var(--orange); --cl: var(--orange-l); --cs: var(--orange); }
.c-yellow { --c: var(--yellow); --cl: var(--yellow-l); --cs: var(--yellow-d); }
.c-green  { --c: var(--green);  --cl: var(--green-l);  --cs: var(--green); }
.c-sky    { --c: var(--sky);    --cl: var(--sky-l);    --cs: var(--sky-d); }
.c-blue   { --c: var(--blue);   --cl: var(--blue-l);   --cs: var(--blue); }
.c-purple { --c: var(--purple); --cl: var(--purple-l); --cs: var(--purple); }
.c-pink   { --c: var(--pink);   --cl: var(--pink-l);   --cs: var(--pink); }
.t-yellow-d { color: var(--yellow-d); }
.t-sky-d { color: var(--sky-d); }

/* ---------- 成绩构成（堆叠条 + 卡片） ---------- */
.score-wrap { background: var(--cream); border-radius: var(--radius); padding: 28px; }
.score-bar { display: flex; height: 54px; border-radius: 14px; overflow: hidden; box-shadow: var(--shadow); }
.score-bar .seg {
  display: flex; align-items: center; justify-content: center;
  color: #fff; font-weight: 800; font-size: 14px; white-space: nowrap; overflow: hidden;
}
.score-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 12px; margin-top: 18px; }
.score-card {
  background: #fff; border-radius: var(--radius-sm); padding: 16px 18px;
  box-shadow: var(--shadow); position: relative; overflow: hidden;
}
.score-card .pts { font-size: 24px; font-weight: 900; }
.score-card .name { font-size: 14px; font-weight: 700; margin-top: 2px; }
.score-card .date { font-size: 12px; color: var(--ink-soft); }
.score-card .dot { position: absolute; top: 14px; right: 14px; width: 12px; height: 12px; border-radius: 50%; background: var(--c); }

/* ---------- 教学周历 ---------- */
.week-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(215px, 1fr)); gap: 12px; }
.week-card {
  border-radius: var(--radius-sm); padding: 16px 18px;
  background: var(--cl); position: relative; overflow: hidden;
  transition: transform 0.15s ease;
}
.week-card:hover { transform: translateY(-3px); }
.week-card .wk { font-size: 12px; font-weight: 700; color: var(--cs); }
.week-card .no {
  position: absolute; right: 10px; top: -8px;
  font-size: 58px; font-weight: 900; color: var(--cs); opacity: 0.14; line-height: 1;
}
.week-card .tt { font-size: 15px; font-weight: 700; margin-top: 4px; position: relative; }

/* ---------- 快速入口 ---------- */
.entry-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 16px; }
.entry-card {
  border-radius: var(--radius); padding: 28px; color: #fff;
  background: var(--c); position: relative; overflow: hidden;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  display: flex; flex-direction: column; gap: 10px; min-height: 150px;
}
.entry-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lift); }
.entry-card .ttl { font-size: 20px; font-weight: 800; }
.entry-card .dsc { font-size: 14px; opacity: 0.92; }
.entry-card .go { margin-top: auto; font-size: 14px; font-weight: 700; }
.entry-card .wm { position: absolute; right: 14px; bottom: -18px; font-size: 90px; font-weight: 900; opacity: 0.16; line-height: 1; }

/* ---------- 顶部登录区 ---------- */
.main-nav { margin-left: auto; }
.header-auth {
  display: flex; align-items: center; gap: 6px; flex-shrink: 0;
}
.auth-who {
  font-size: 13px; font-weight: 700; color: var(--ink);
  background: var(--sky-l); color: var(--sky-d);
  padding: 5px 12px; border-radius: 999px;
  max-width: 150px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.auth-btn {
  border: none; cursor: pointer; font-family: inherit;
  background: var(--cream); color: var(--ink-soft);
  font-size: 13px; font-weight: 700;
  padding: 6px 14px; border-radius: 999px;
  transition: all 0.15s ease;
}
.auth-btn:hover { background: var(--sky-l); color: var(--sky-d); }
.auth-btn--primary { background: var(--ink); color: #fff; }
.auth-btn--primary:hover { background: var(--sky-d); color: #fff; }
.site-login { width: min(440px, 94vw); }

/* ---------- 十二次课程作业列表 ---------- */
.hw-item {
  border-radius: var(--radius); background: var(--cl);
  padding: 14px 18px; margin-bottom: 10px;
  transition: box-shadow 0.15s ease;
}
.hw-item:hover { box-shadow: var(--shadow); }
.hw-head { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.hw-no {
  width: 46px; height: 46px; border-radius: 14px; flex-shrink: 0;
  background: var(--cs); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 20px; font-weight: 900;
}
.hw-info { flex: 1; min-width: 180px; }
.hw-deadline { font-size: 14.5px; font-weight: 700; }
.hw-state-text { font-size: 12px; color: var(--ink-soft); }
.hw-badge, .hw-mine-badge {
  font-size: 12.5px; font-weight: 800;
  border-radius: 999px; padding: 4px 13px;
  white-space: nowrap; line-height: 1.5;
}
.hw-badge { color: #fff; background: var(--cs); }
.hw-mine-badge { color: var(--ink-soft); background: rgba(43, 45, 66, 0.10); }
.hw-mine-badge.ok { color: var(--green); background: var(--green-l); }
.hw-grade-badge { font-size: 12px; font-weight: 800; border-radius: 999px; padding: 3px 10px; white-space: nowrap; }
.hw-grade-badge.graded { color: var(--purple); background: var(--purple-l); }
.hw-grade-badge.no { color: var(--ink-soft); background: rgba(43, 45, 66, 0.10); }
.hw-grade-badge.pass { color: var(--green); background: var(--green-l); }
.hw-grade-badge.fail { color: var(--pink); background: var(--pink-l); }
.hw-grade-badge.pending { color: var(--yellow-d); background: var(--yellow-l); }
.hw-grade-comment {
  background: rgba(255, 255, 255, 0.75); border-radius: 10px;
  padding: 7px 12px; font-size: 12.5px; margin-bottom: 10px;
}
.hw-grade-comment b { color: var(--purple); margin-right: 6px; }
.hw-grade-entry { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.hw-grade-entry select, .hw-grade-entry input[type="text"] {
  padding: 7px 10px; border-radius: 10px; border: 1.5px solid #E3DFD3;
  font-family: inherit; font-size: 13px; background: #FAF9F5; max-width: 230px;
}
.hw-grade-entry textarea {
  padding: 7px 10px; border-radius: 10px; border: 1.5px solid #E3DFD3;
  font-family: inherit; font-size: 13px; line-height: 1.6; background: #FAF9F5;
  resize: vertical; min-height: 58px;
}
.hw-toggle { flex-shrink: 0; }
.hw-body {
  margin-top: 12px; padding-top: 12px;
  border-top: 2px dashed rgba(43, 45, 66, 0.10);
}
.hw-admin-row { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.hw-admin-row .hw-count { flex: 1; min-width: 120px; }
.hw-item .lab1-actions { justify-content: flex-end; margin-top: 10px; }

/* 作业单内容块（展开后显示） */
.hw-content {
  background: rgba(255, 255, 255, 0.75);
  border-radius: var(--radius-sm);
  padding: 12px 15px; margin-bottom: 10px;
  font-size: 13px; line-height: 1.7;
}
.hw-content > b { display: block; font-size: 13.5px; margin-bottom: 4px; }
.hw-content .hc-sec { margin-top: 6px; }
.hw-content .hc-sec b { display: inline; color: var(--sky-d); margin-right: 6px; }
.hw-content .hc-dl { margin-top: 8px; }
.hw-guest-hint {
  background: var(--blue-l); color: var(--sky-d);
  border-radius: 10px; padding: 7px 12px;
  font-size: 12.5px; font-weight: 600; margin-bottom: 10px;
}

/* ---------- 成绩查询 ---------- */
.gr-scorebar { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 18px; }
.gr-big {
  flex: 1; min-width: 180px; background: #fff; border-radius: var(--radius-sm);
  padding: 18px 22px; box-shadow: var(--shadow);
  display: flex; align-items: baseline; gap: 8px;
}
.gr-big span { font-size: 40px; font-weight: 900; color: var(--purple); }
.gr-big small { color: var(--ink-soft); font-size: 13px; }
.gr-table { width: 100%; border-collapse: collapse; font-size: 13.5px; background: #fff; }
.gr-table th, .gr-table td {
  border-bottom: 1px solid #EFECE2; padding: 9px 12px; text-align: left;
  white-space: nowrap;
}
.gr-table thead th { background: var(--purple-l); color: var(--ink); font-weight: 700; }
.gr-table tbody tr:hover { background: var(--cream); }
.gr-table--all { font-size: 12.5px; }
.gr-table--all thead th { background: var(--pink-l); }
.gr-admin-tools {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 14px; margin-bottom: 12px;
}
.gr-tool {
  background: #fff; border-radius: var(--radius-sm); padding: 14px 16px;
  box-shadow: var(--shadow);
}
.gr-tool b { display: block; margin-bottom: 8px; }
.gr-form-row { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.gr-form-row select, .gr-form-row input[type="text"], .gr-form-row input[type="file"] {
  padding: 7px 10px; border-radius: 10px; border: 1.5px solid #E3DFD3;
  font-family: inherit; font-size: 13px; background: #FAF9F5;
  max-width: 240px;
}

/* ---------- 子页横幅 ---------- */
.page-hero {
  margin-top: 28px; border-radius: 26px; padding: 42px 44px;
  background: var(--cl, var(--blue-l)); position: relative; overflow: hidden;
}
.page-hero .kicker { margin-bottom: 14px; }
.page-hero h1 { font-size: clamp(26px, 4vw, 36px); margin-bottom: 10px; }
.page-hero p { color: var(--ink-soft); max-width: 720px; font-size: 15px; }
.page-hero .wm { position: absolute; right: 24px; top: -20px; font-size: 170px; font-weight: 900; color: var(--c); opacity: 0.09; line-height: 1; pointer-events: none; }

/* ---------- 讲次卡片（课件页） ---------- */
.lec-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 16px; }
.lec-card {
  border-radius: var(--radius); padding: 22px;
  background: var(--cl); position: relative; overflow: hidden;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
  display: flex; flex-direction: column; gap: 10px; min-height: 158px;
}
.lec-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.lec-card .top { display: flex; align-items: center; gap: 10px; }
.lec-card .week { font-size: 12px; color: var(--ink-soft); font-weight: 600; }
.lec-card h3 { font-size: 17px; line-height: 1.45; position: relative; z-index: 1; }
.lec-card .meta { font-size: 12.5px; color: var(--ink-soft); }
.lec-card .dl { margin-top: auto; align-self: flex-start; }
.lec-card .no {
  position: absolute; right: 12px; bottom: -14px;
  font-size: 88px; font-weight: 900; color: var(--cs); opacity: 0.13; line-height: 1;
  pointer-events: none;
}

/* ---------- 项目卡片 ---------- */
.proj-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(290px, 1fr)); gap: 16px; }
.proj-card {
  border-radius: var(--radius); padding: 26px;
  background: var(--cl); position: relative; overflow: hidden;
  display: flex; flex-direction: column; gap: 10px;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.proj-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.proj-card h3 { font-size: 19px; }
.proj-card .slogan { font-size: 14px; font-weight: 700; color: var(--cs); }
.proj-card p { font-size: 13.5px; color: var(--ink-soft); }
.proj-card .dl { margin-top: auto; padding-top: 8px; }
.proj-card .no { position: absolute; right: 14px; top: -12px; font-size: 80px; font-weight: 900; color: var(--cs); opacity: 0.12; line-height: 1; }

/* ---------- 小组贴纸墙 ---------- */
.group-block { border-radius: var(--radius); background: var(--cl); padding: 22px 24px; margin-bottom: 14px; }
.group-block .gb-head { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; flex-wrap: wrap; }
.group-block .gb-head .cnt { font-size: 13px; color: var(--ink-soft); }
.group-chips { display: flex; flex-wrap: wrap; gap: 10px; }
.group-chips a {
  display: inline-flex; align-items: baseline; gap: 7px;
  background: #fff; border-radius: 999px; padding: 7px 16px;
  font-size: 13.5px; font-weight: 600; color: var(--ink);
  box-shadow: 0 2px 8px rgba(43,45,66,0.07);
  transition: transform 0.15s ease;
}
.group-chips a:hover { transform: translateY(-2px); }
.group-chips a b { color: var(--c); font-weight: 900; }

/* ---------- 资料下载卡 ---------- */
.dl-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(250px, 1fr)); gap: 14px; }
.dl-card {
  background: var(--cl); border-radius: var(--radius); padding: 22px;
  display: flex; flex-direction: column; gap: 8px; position: relative; overflow: hidden;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.dl-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.dl-card h3 { font-size: 16px; padding-right: 58px; }
.dl-card .meta { font-size: 12.5px; color: var(--ink-soft); }
.dl-card .btn { align-self: flex-start; margin-top: 6px; }
.dl-card .ic {
  position: absolute; top: 18px; right: 18px; width: 34px; height: 34px;
  border-radius: 10px; background: var(--cs); color: #fff;
  display: flex; align-items: center; justify-content: center;
  font-size: 12px; font-weight: 900;
}

/* ---------- 实验时间线（考核页） ---------- */
.timeline { position: relative; padding-left: 34px; }
.timeline::before {
  content: ""; position: absolute; left: 10px; top: 8px; bottom: 8px;
  width: 4px; border-radius: 2px;
  background: linear-gradient(180deg, var(--pink), var(--red), var(--orange), var(--yellow), var(--green));
}
.tl-item { position: relative; margin-bottom: 18px; }
.tl-item .pt {
  position: absolute; left: -31px; top: 22px;
  width: 16px; height: 16px; border-radius: 50%;
  background: var(--cs); border: 3.5px solid #fff; box-shadow: 0 0 0 2px var(--cs);
}
.tl-card {
  border-radius: var(--radius); background: var(--cl); padding: 22px 24px;
  display: flex; flex-wrap: wrap; gap: 14px; align-items: center;
}
.tl-card .when { min-width: 150px; }
.tl-card .when .d { font-size: 19px; font-weight: 900; color: var(--cs); }
.tl-card .when .w { font-size: 12px; color: var(--ink-soft); }
.tl-card .body { flex: 1; min-width: 220px; }
.tl-card .body h3 { font-size: 17px; margin-bottom: 4px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.tl-card .body p { font-size: 13.5px; color: var(--ink-soft); }
.tl-card .pts-badge {
  font-size: 13px; font-weight: 800; color: #fff;
  background: var(--cs); border-radius: 999px; padding: 3px 12px;
}

/* ---------- 提示横幅 ---------- */
.note-band {
  border-radius: var(--radius-sm); background: var(--yellow-l);
  padding: 16px 20px; font-size: 14px; color: var(--ink);
  margin-top: 22px;
}
.note-band b { color: var(--yellow-d); }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--ink); color: #C9CBD9; margin-top: 72px; padding: 44px 0 36px; }
.site-footer .inner { display: flex; flex-wrap: wrap; gap: 30px; justify-content: space-between; }
.site-footer h4 { color: #fff; font-size: 16px; margin-bottom: 10px; }
.site-footer ul { font-size: 13.5px; }
.site-footer li { margin-bottom: 6px; }
.site-footer a:hover { color: #fff; }
.site-footer .copy { border-top: 1px solid rgba(255,255,255,0.12); margin-top: 30px; padding-top: 20px; font-size: 12.5px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 10px; }

/* ---------- 响应式 ---------- */
@media (max-width: 860px) {
  .hero { padding: 40px 28px; }
  .hero .float-stickers { display: none; }
  .hero .watermark { font-size: 170px; }
  .page-hero { padding: 32px 26px; }
}
@media (max-width: 720px) {
  .nav-toggle { display: block; }
  .main-nav {
    display: none; position: absolute; top: 64px; left: 0; right: 0;
    background: #fff; flex-direction: column; padding: 12px 20px 18px;
    box-shadow: 0 14px 28px rgba(43,45,66,0.2); gap: 4px;
  }
  .main-nav.open { display: flex; }
  .main-nav a { padding: 11px 16px; }
  .section { padding: 40px 0 4px; }
  .score-bar .seg { font-size: 12px; }
  .tl-card .when { min-width: 100%; }
}

/* ============================================================
   实验一在线提交（labs 页：提交卡片 + 倒计时 + 对话框）
   ============================================================ */

/* 深色高亮提交卡（浅色卡堆里最醒目的一张，横跨两列） */
.dl-card--submit {
  grid-column: span 2;
  background: var(--ink);
  color: #fff;
}
.dl-card--submit h3 { color: #fff; font-size: 18px; }
.dl-card--submit .ic { background: var(--yellow); color: var(--ink); }
.dl-card--submit .meta { color: #C9CBD9; }
.lab1-countdown {
  background: rgba(255, 255, 255, 0.10);
  border-radius: var(--radius-sm);
  padding: 12px 16px;
}
.lab1-countdown .cd-label { display: block; font-size: 12px; color: #C9CBD9; }
.lab1-countdown .cd-time {
  display: block; font-size: 24px; font-weight: 900; margin-top: 2px;
  color: var(--yellow); font-variant-numeric: tabular-nums; letter-spacing: 0.5px;
}
.lab1-countdown.cd-over .cd-time { color: var(--pink); }
.lab1-state { min-height: 18px; }
.lab1-state.ok { color: #9BE8CD; }
.lab1-state.err { color: #FFB4C0; }

/* 红色提示横幅（截止提醒） */
.note-band--red { background: var(--red-l); }
.note-band--red b { color: var(--red); }

/* 提交对话框 */
.lab1-dialog {
  border: none; border-radius: var(--radius); padding: 0;
  width: min(600px, 94vw); max-height: 92vh; overflow: auto;
  margin: auto; /* 文件头部的 * {margin:0} 会盖掉 UA 默认居中，必须显式恢复 */
  box-shadow: 0 24px 60px rgba(43, 45, 66, 0.35);
  color: var(--ink);
}
.lab1-dialog::backdrop { background: rgba(43, 45, 66, 0.55); }
.lab1-dialog-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 22px 26px 0;
}
.lab1-dialog-head h3 { font-size: 20px; }
.lab1-dialog-close {
  border: none; background: var(--cream); color: var(--ink-soft);
  width: 34px; height: 34px; border-radius: 50%;
  font-size: 18px; line-height: 1; cursor: pointer;
}
.lab1-dialog-close:hover { background: var(--red-l); color: var(--red); }
.lab1-dialog-deadline {
  margin: 12px 26px 0; padding: 7px 14px;
  background: var(--yellow-l); color: var(--yellow-d);
  border-radius: 999px; font-size: 13px; font-weight: 700;
  font-variant-numeric: tabular-nums;
}
.lab1-dialog-body { padding: 18px 26px 24px; }
.lab1-dialog-closed {
  background: var(--red-l); border-radius: var(--radius-sm);
  padding: 24px 20px; text-align: center; font-size: 15px;
}
.lab1-dialog-closed b { color: var(--red); }
.lab1-dialog-closed .sub { font-size: 13px; color: var(--ink-soft); margin-top: 6px; }
.lab1-field { display: block; margin-bottom: 14px; }
.lab1-field > span {
  display: block; font-size: 13px; font-weight: 700;
  margin-bottom: 6px; color: var(--ink-soft);
}
.lab1-field select,
.lab1-field input[type="file"] {
  width: 100%; padding: 10px 12px; border-radius: var(--radius-sm);
  border: 2px dashed #E3DFD3; background: #FAF9F5;
  font-size: 14px; font-family: inherit; color: var(--ink);
}
.lab1-field select:focus,
.lab1-field input[type="file"]:focus { outline: none; border-color: var(--sky); }
.lab1-filelist { margin: 0 0 12px; font-size: 12.5px; color: var(--ink-soft); }
.lab1-filelist li {
  padding: 5px 2px; border-bottom: 1px dashed #EFECE2;
  display: flex; justify-content: space-between; gap: 10px; flex-wrap: wrap;
}
.lab1-filelist li b { color: var(--ink); font-weight: 600; }
.lab1-filelist li.bad, .lab1-filelist li.bad b { color: var(--red); }
.lab1-progress { display: flex; align-items: center; gap: 12px; margin: 6px 0 12px; }
.lab1-progress .bar {
  flex: 1; height: 10px; border-radius: 5px;
  background: var(--cream); overflow: hidden;
}
.lab1-progress .bar i {
  display: block; height: 100%; width: 0%;
  background: var(--green); border-radius: 5px;
  transition: width 0.2s ease;
}
.lab1-progress span {
  font-size: 12.5px; color: var(--ink-soft);
  font-variant-numeric: tabular-nums; min-width: 92px; text-align: right;
}
.lab1-msg {
  border-radius: var(--radius-sm); padding: 12px 14px;
  font-size: 13.5px; margin: 0 0 12px; line-height: 1.6;
}
.lab1-msg.ok { background: var(--green-l); color: var(--green); }
.lab1-msg.err { background: var(--red-l); color: var(--red); }
.lab1-actions { display: flex; justify-content: flex-end; gap: 10px; }
.lab1-tips {
  margin-top: 14px; font-size: 12px; color: var(--ink-soft);
  background: var(--cream); border-radius: var(--radius-sm); padding: 10px 14px;
}
.lab1-userbar {
  display: flex; align-items: center; justify-content: space-between; gap: 10px;
  background: var(--sky-l); border-radius: var(--radius-sm);
  padding: 9px 14px; margin-bottom: 14px; font-size: 13.5px; font-weight: 700;
  flex-wrap: wrap;
}
.lab1-userbtns { display: flex; gap: 6px; flex-wrap: wrap; }
.lab1-mini {
  border: none; cursor: pointer; font-family: inherit;
  background: #fff; color: var(--sky-d);
  font-size: 12.5px; font-weight: 700;
  padding: 4px 12px; border-radius: 999px;
  box-shadow: 0 1px 4px rgba(43, 45, 66, 0.12);
  transition: transform 0.15s ease;
}
.lab1-mini:hover { transform: translateY(-1px); }
.lab1-notice {
  background: var(--yellow-l); color: var(--yellow-d);
  border-radius: var(--radius-sm); padding: 10px 14px;
  font-size: 13.5px; font-weight: 700; margin-bottom: 14px;
}
.lab1-field input[type="text"],
.lab1-field input[type="password"] {
  width: 100%; padding: 10px 12px; border-radius: var(--radius-sm);
  border: 2px solid #E3DFD3; background: #FAF9F5;
  font-size: 14px; font-family: inherit; color: var(--ink);
}
.lab1-field input[type="text"]:focus,
.lab1-field input[type="password"]:focus { outline: none; border-color: var(--sky); }

@media (max-width: 720px) {
  .dl-card--submit { grid-column: auto; }
  .lab1-countdown .cd-time { font-size: 20px; }
}

/* 实验一未合格定向通知横幅（全站 · 登录学生按成绩判定显示） */
.pln-banner {
  display: flex; align-items: flex-start; gap: 10px;
  background: var(--red-l);
  border-bottom: 2px solid var(--red);
  padding: 10px 22px;
  font-size: 13.5px; line-height: 1.8;
}
.pln-banner .pln-banner-body { flex: 1; min-width: 0; }
.pln-banner b { color: var(--red); margin-right: 8px; }
.pln-banner a { color: var(--red); text-decoration: underline; }
.pln-banner-close {
  flex-shrink: 0; border: none; background: transparent;
  font-size: 18px; line-height: 1; cursor: pointer;
  color: var(--red); padding: 2px 6px;
}