/* 登入頁、老師後台、學生首頁共用的樣式（深色，和上課畫面一致） */
:root {
  color-scheme: dark;
  --chrome: #121519; --panel: #1c2026; --panel-2: #252a32; --line: #333a44;
  --text: #e9edf1; --muted: #98a2ad; --accent: #4d8dff; --accent-ink: #fff;
  --good: #3fb67a; --warn: #f0a53a; --bad: #e5674d; --live: #e5484d;
  --paper: #fff; --print: #1c2433; --ink: #1f4fd1; --ink-red: #d1342a;
  --font-hand: "LXGW WenKai TC", "Kaiti TC", "DFKai-SB", serif;
  --font-ui: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", system-ui, sans-serif;
}
* { box-sizing: border-box; }
[hidden] { display: none !important; }
html, body { background: var(--chrome); }
body { margin: 0; color: var(--text); font-family: var(--font-ui); font-size: 15px; line-height: 1.55;
  padding: 20px max(16px, env(safe-area-inset-right, 0px)) 40px max(16px, env(safe-area-inset-left, 0px)); }
button, input, select { font: inherit; color: inherit; }
button { cursor: pointer; }
button:focus-visible, input:focus-visible, select:focus-visible, a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
a { color: var(--accent); }
h1 { font-size: 1.45rem; margin: 0; }
h2 { font-size: 1.1rem; margin: 0; }
.wrap { max-width: 1080px; margin: 0 auto; display: flex; flex-direction: column; gap: 16px; }
.top { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 16px; }
.top .grow { flex: 1; }
.muted { color: var(--muted); }
.small { font-size: .84rem; }
.card { background: var(--panel); border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px; display: flex; flex-direction: column; gap: 12px; min-width: 0; }
.row { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.grid2 { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 10px; }
label.field { display: flex; flex-direction: column; gap: 4px; font-size: .84rem; color: var(--muted); min-width: 0; }
textarea { font: inherit; color: inherit; background: var(--panel-2); border: 1px solid var(--line); border-radius: 8px; padding: 8px 10px; width: 100%; min-width: 0; resize: vertical; line-height: 1.5; }
.exedit { border: 1px solid var(--line); border-radius: 12px; padding: 12px 14px; display: flex; flex-direction: column; gap: 8px; }
.exedit h3 { margin: 0; font-size: 1rem; }
input[type="file"] { max-width: 100%; }
input[type="text"], input[type="password"], input[type="number"], input[type="datetime-local"], select {
  background: var(--panel-2); border: 1px solid var(--line); border-radius: 8px; padding: 8px 10px; min-width: 0; width: 100%; }
.btn { border: 1px solid var(--line); background: var(--panel-2); border-radius: 999px; padding: 7px 16px; font-weight: 500; }
.btn:hover { background: #2e343d; }
.btn:disabled { opacity: .45; cursor: not-allowed; }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--accent-ink); font-weight: 700; }
.btn.danger { background: transparent; border-color: var(--bad); color: var(--bad); }
.btn.small { padding: 4px 12px; font-size: .84rem; }
.note { margin: 0; font-size: .86rem; color: var(--muted); min-height: 1.2em; }
.note.err { color: var(--bad); }
.note.ok { color: var(--good); }
.tabs { display: flex; gap: 6px; border-bottom: 1px solid var(--line); flex-wrap: wrap; }
.tabs button { background: none; border: 0; border-bottom: 2px solid transparent; padding: 8px 14px; color: var(--muted); font-weight: 500; }
.tabs button[aria-selected="true"] { color: var(--text); border-bottom-color: var(--accent); }
.tablewrap { overflow-x: auto; }
table.list { width: 100%; border-collapse: collapse; font-size: .9rem; min-width: 560px; }
table.list th, table.list td { text-align: left; padding: 9px 10px; border-bottom: 1px solid var(--line); vertical-align: middle; }
table.list th { color: var(--muted); font-weight: 500; font-size: .8rem; }
table.list td.num { font-variant-numeric: tabular-nums; }
.pill { display: inline-block; font-size: .76rem; padding: 1px 9px; border-radius: 999px; border: 1px solid var(--line); white-space: nowrap; }
.pill.open { border-color: var(--good); color: var(--good); }
.pill.done { color: var(--muted); }
.pill.missed { border-color: var(--warn); color: var(--warn); }
.pill.flag { border-color: var(--warn); color: var(--warn); }
.topic { border: 1px solid var(--line); border-radius: 10px; padding: 10px 12px; display: flex; flex-direction: column; gap: 6px; }
.topic-h { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; justify-content: space-between; }
.topic-h b { font-weight: 500; }
.ex-list { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 4px 12px; }
.ex-list label { display: flex; gap: 8px; align-items: baseline; font-size: .88rem; }
.mins { display: inline-flex; align-items: center; gap: 6px; font-size: .84rem; color: var(--muted); }
.mins input { width: 70px; text-align: right; }
.total { font-variant-numeric: tabular-nums; }
.total.bad b { color: var(--warn); }
.modal { position: fixed; inset: 0; background: rgba(0,0,0,.6); display: flex; align-items: flex-start; justify-content: center; padding: 30px 16px; overflow-y: auto; z-index: 20; }
.modal .card { width: min(820px, 100%); }
/* 聯絡簿 */
.book { background: var(--paper); color: var(--print); border-radius: 8px; padding: 16px; overflow-x: auto; }
.book h3 { margin: 0 0 10px; color: var(--ink-red); font-family: var(--font-hand); font-size: 1.5rem; letter-spacing: .2em; text-align: center; }
.book table { width: 100%; min-width: 460px; border-collapse: collapse; font-size: .92rem; }
.book th, .book td { border: 1px solid #c9d3e0; padding: 7px 10px; vertical-align: top; text-align: left; white-space: pre-wrap; }
.book th { width: 6.5em; background: #f3f6fa; font-weight: 500; white-space: nowrap; }
.book td ul { margin: 0; padding-left: 18px; }
.book .comment { font-family: var(--font-hand); color: var(--ink); font-size: 1.08rem; }
.book .sign { height: 40px; }
.notice { background: var(--paper); color: var(--print); border-left: 4px solid var(--ink-red); border-radius: 6px; padding: 12px 14px; white-space: pre-wrap; font-size: .92rem; line-height: 1.7; }
.classes { display: flex; flex-direction: column; gap: 8px; }
.cls { display: flex; flex-wrap: wrap; gap: 8px 14px; align-items: center; padding: 12px 14px; border: 1px solid var(--line); border-radius: 10px; }
.cls .grow { flex: 1 1 220px; min-width: 0; }
.cls .when { font-variant-numeric: tabular-nums; }
.login { max-width: 380px; margin: 8vh auto 0; }