/* Trang tạo quiz Canvas từ đề Word – giao diện riêng, gọn: màu của trang trolygiaovien.id.vn (tai-ve.html), câu hỏi
   hiện như trên Canvas (khung câu, đầu khung có số điểm). Máy tính trước: hai cột (bên trái: kết nối, file, xem lại;
   bên phải: thông tin quiz, luôn thấy khi cuộn); điện thoại: một cột theo đúng thứ tự 1–4. Sáng/tối theo máy. */

:root {
  --bg: #f7f7fb;
  --card: #ffffff;
  --surface-2: #fafafd;
  --head: #f2f3f7;
  --text: #1f2330;
  --muted: #5d6273;
  --line: #e2e3ec;
  --line-strong: #c9cbd8;
  --accent: #5b5fd6;
  --accent-hover: #4b4fc4;
  --accent-soft: #eef0ff;
  --on-accent: #ffffff;
  --input-bg: #ffffff;
  --hover: #f4f5fb;
  --ok: #157a3c; --ok-bg: #e8f5ec; --ok-stroke: #a9d8b8;
  --bad: #c42b1c; --bad-bg: #fdecea; --bad-stroke: #f0b3ac;
  --warn-text: #865300; --warn-bg: #fff6dc; --warn-head: #ffedb8; --warn-stroke: #e8c46a;
  --shadow: 0 1px 2px rgb(0 0 0 / 0.06), 0 0 1px rgb(0 0 0 / 0.08);
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #1b1c22;
    --card: #24252d;
    --surface-2: #2a2b34;
    --head: #2d2e38;
    --text: #e9e9ef;
    --muted: #a3a6b4;
    --line: #383946;
    --line-strong: #4c4e5e;
    --accent: #8b8ff0;
    --accent-hover: #a1a4f4;
    --accent-soft: #2c2e48;
    --on-accent: #12132a;
    --input-bg: #1d1e25;
    --hover: #2c2d38;
    --ok: #5fd08a; --ok-bg: #19362a; --ok-stroke: #2e6a48;
    --bad: #ff8a7a; --bad-bg: #3f1d19; --bad-stroke: #7d3128;
    --warn-text: #f3c25a; --warn-bg: #3a2f12; --warn-head: #4a3b14; --warn-stroke: #7a6020;
    --shadow: 0 1px 3px rgb(0 0 0 / 0.4);
    color-scheme: dark;
  }
}

/* ---------- Nền tảng ---------- */
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--text);
  font: 16px/1.55 -apple-system, "Segoe UI", system-ui, Roboto, sans-serif;
}
a { color: var(--accent); }
h1, h2, h3, h4 { line-height: 1.25; }
[hidden] { display: none !important; }
.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0 0 0 0); white-space: nowrap; border: 0;
}
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.wrap { max-width: 1240px; margin: 0 auto; padding: 0 16px; }
.top { padding: 26px 0 6px; }
.brand { color: var(--accent); font-weight: 700; text-decoration: none; }
.brand:hover { text-decoration: underline; }
h1 { font-size: clamp(24px, 4vw, 32px); margin: 4px 0 6px; }
.lead { color: var(--muted); margin: 0 0 12px; }
.foot { color: var(--muted); font-size: 14px; padding-top: 4px; padding-bottom: 32px; }

/* ---------- Bố cục ---------- */
.layout { display: grid; grid-template-columns: minmax(0, 1fr); gap: 16px; align-items: start; }
.col-main { display: grid; gap: 16px; min-width: 0; }
@media (min-width: 1080px) {
  .layout { grid-template-columns: minmax(0, 1fr) 390px; }
  .quiz { position: sticky; top: 16px; max-height: calc(100vh - 32px); overflow: auto; }
}

.card {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px; padding: 18px 20px;
  box-shadow: var(--shadow); min-width: 0;
}
.card h2 { font-size: 20px; margin: 0 0 12px; display: flex; align-items: center; }
.num {
  display: inline-flex; align-items: center; justify-content: center; flex: none;
  width: 28px; height: 28px; border-radius: 50%; margin-right: 10px;
  background: var(--accent-soft); color: var(--accent); font-size: 15px; font-weight: 700;
}
.locked { opacity: 0.6; }

/* ---------- Ô nhập, nút ---------- */
input[type="text"], input[type="password"], input[type="number"], select {
  font: inherit; color: var(--text); background: var(--input-bg);
  border: 1px solid var(--line-strong); border-radius: 8px; padding: 7px 10px; min-height: 40px; min-width: 0;
}
input:disabled, select:disabled { opacity: 0.6; }
input[aria-invalid="true"] { border-color: var(--bad); }
.btn {
  font: inherit; font-weight: 600; color: var(--text); background: var(--card);
  border: 1px solid var(--line-strong); border-radius: 8px; padding: 7px 16px; min-height: 40px; cursor: pointer;
}
.btn:hover:not(:disabled) { background: var(--hover); }
.btn.primary { background: var(--accent); border-color: var(--accent); color: var(--on-accent); }
.btn.primary:hover:not(:disabled) { background: var(--accent-hover); border-color: var(--accent-hover); }
.btn.danger { color: var(--bad); border-color: var(--bad-stroke); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn.big { width: 100%; font-size: 17px; padding: 11px 16px; }
.link-btn { display: inline-block; text-decoration: none; }
.row { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.row input { flex: 1 1 220px; }
.lbl { display: block; font-weight: 600; margin-bottom: 6px; }
.field { margin-bottom: 12px; }
.check { display: inline-flex; align-items: center; gap: 8px; cursor: pointer; }
.check input { width: 18px; height: 18px; margin: 0; accent-color: var(--accent); }
.check-line { display: flex; flex-wrap: wrap; align-items: center; gap: 4px 12px; margin: 12px 0 0; }
.check-line .hint { margin: 0; }

/* ---------- Lời báo ---------- */
.msg { margin: 8px 0 0; font-size: 14px; }
.msg.ok, .ok-text { color: var(--ok); }
.msg.warn { color: var(--warn-text); }
.msg.error { color: var(--bad); }
.hint { color: var(--muted); font-size: 14px; margin: 6px 0 0; }
.hint.warn { color: var(--warn-text); }
.hint.error { color: var(--bad); }
.notice { border: 1px solid; border-radius: 10px; padding: 12px 14px; margin-top: 14px; }
.notice.ok { background: var(--ok-bg); border-color: var(--ok-stroke); }
.notice.error { background: var(--bad-bg); border-color: var(--bad-stroke); }
.notice p { margin: 0 0 8px; }
.notice > :last-child { margin-bottom: 0; }
.notice .row { margin: 4px 0 8px; }

/* ---------- 1. Kết nối ---------- */
.connected { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 12px; }
.connected p { margin: 0; font-weight: 600; }
.guide { margin-top: 14px; border-top: 1px solid var(--line); padding-top: 10px; }
.guide summary { cursor: pointer; font-weight: 600; color: var(--accent); }
.steps { margin: 10px 0 4px; padding-left: 22px; }
.steps li { margin-bottom: 6px; }

/* ---------- 2. File ---------- */
.drop {
  border: 2px dashed var(--line-strong); border-radius: 12px; padding: 20px 16px; text-align: center;
  background: var(--surface-2); transition: border-color 0.15s, background 0.15s;
}
.drop.over { border-color: var(--accent); background: var(--accent-soft); }
.drop p { margin: 0 0 10px; color: var(--muted); }
@media (pointer: coarse) and (max-width: 760px) {
  .drop { padding: 14px 16px; }
  .drop p { display: none; } /* điện thoại không kéo thả được */
}
.file-info { margin-top: 12px; }
.file-name { margin: 0; font-weight: 700; overflow-wrap: anywhere; }
.summary { margin: 2px 0 0; }
.warnings { margin: 12px 0 0; padding: 10px 14px 10px 30px; border-radius: 10px; background: var(--warn-bg); color: var(--warn-text); font-size: 14px; }
.warnings li { margin: 2px 0; }

/* ---------- 3. Xem lại (chỉ xem, như Canvas; mặc định thu gọn) ---------- */
.review-bar { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 12px; }
.review-bar .msg { margin: 0; font-weight: 600; flex: 1 1 220px; }
.review-body { margin-top: 12px; display: grid; gap: 8px; }
.review-body > .hint { margin: 0; }
.fix-box { display: grid; gap: 8px; justify-items: start; }
.fix-box .hint { margin: 0; }
.problems {
  margin: 0; padding: 8px 14px 8px 30px; border: 1px solid var(--bad-stroke); border-radius: 10px; justify-self: stretch;
  background: var(--bad-bg); color: var(--bad); font-size: 14px; font-weight: 600; scroll-margin: 80px;
}
.problems:focus { outline: none; }
.problems:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.problems li { margin: 2px 0; overflow-wrap: anywhere; }
#review { scroll-margin-top: 12px; }
#mathtype { scroll-margin: 80px; }
#mathtype:focus { outline: none; }
.questions { margin-top: 0; }
.givens { margin: 14px 0 0; padding: 10px 14px; border-radius: 10px; background: var(--accent-soft); }
.givens-title { margin: 0 0 4px; font-size: 13px; font-weight: 700; color: var(--accent); text-transform: uppercase; letter-spacing: 0.02em; }
.group { margin-top: 20px; }
.group-head {
  display: flex; flex-wrap: wrap; align-items: center; gap: 6px 14px;
  padding: 0 0 8px; border-bottom: 2px solid var(--accent-soft);
}
.group-name { margin: 0; font-size: 18px; }
.pts-edit { display: inline-flex; align-items: center; gap: 6px; font-size: 15px; }
.pts-input { width: 4.6em; text-align: center; min-height: 34px !important; padding: 4px 6px !important; }
.group-total { color: var(--muted); font-size: 14px; }
.group-head .msg { flex-basis: 100%; margin: 0; }
.text-item { margin: 12px 0; padding: 10px 14px; border: 1px dashed var(--line-strong); border-radius: 8px; background: var(--surface-2); }

.q { margin: 12px 0; border: 1px solid var(--line-strong); border-radius: 8px; background: var(--card); overflow: hidden; scroll-margin: 80px; }
.q:focus { outline: none; }
.q:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.q-head {
  display: flex; justify-content: space-between; align-items: baseline; gap: 12px;
  padding: 7px 14px; background: var(--head); border-bottom: 1px solid var(--line);
}
.q-label { margin: 0; font-size: 15px; }
.q-pts { color: var(--muted); font-size: 14px; white-space: nowrap; }
.q-body { padding: 12px 14px 14px; }
/* câu phải sửa trong Word (thiếu đáp án, phương án trống…): đỏ */
.q.problem { border-color: var(--bad-stroke); background: var(--bad-bg); }
.q.problem .q-head { background: var(--bad-bg); border-bottom-color: var(--bad-stroke); }
.q-problems { margin: 10px 0 0; padding-left: 20px; font-size: 14px; font-weight: 600; color: var(--bad); }
.q-problems li { margin: 2px 0; overflow-wrap: anywhere; }

.rich { overflow-wrap: anywhere; }
.rich p { margin: 0 0 6px; }
.rich > :last-child { margin-bottom: 0; }
.rich img { max-width: 100%; height: auto; vertical-align: middle; background: #fff; border-radius: 2px; }
.rich table { border-collapse: collapse; margin: 6px 0; max-width: 100%; display: block; overflow-x: auto; }
.rich table[border] td, .rich table[border] th { border: 1px solid var(--line-strong); }
.rich td, .rich th { padding: 4px 8px; vertical-align: top; }
.rich math { font-size: 1.08em; }
/* temml vẽ \overline, \underline, \boxed, \cancel bằng <menclose>; Chrome (MathML Core) bỏ qua thuộc tính notation nên
   không có nét nào – vẽ bằng CSS như Temml-Local.css (chỉ Chrome: Safari, Firefox tự vẽ menclose) */
@supports (not (-webkit-backdrop-filter: blur(1px))) and (not (-moz-appearance: none)) {
  menclose { position: relative; padding: 0.5ex 0; }
  .tml-overline { padding: 0.1em 0 0; border-top: 0.065em solid; }
  .tml-underline { padding: 0 0 0.1em; border-bottom: 0.065em solid; }
  .tml-fbox { padding: 3pt; border: 1px solid; }
  .tml-cancel { display: inline-block; position: absolute; left: 0.5px; bottom: 0; width: 100%; height: 100%; background-color: currentColor; }
  .upstrike { clip-path: polygon(0.05em 100%, 0em calc(100% - 0.05em), calc(100% - 0.05em) 0em, 100% 0.05em); }
  .downstrike { clip-path: polygon(0em 0.05em, 0.05em 0em, 100% calc(100% - 0.05em), calc(100% - 0.05em) 100%); }
  .tml-xcancel { clip-path: polygon(0.05em 0em, 0em 0.05em, calc(50% - 0.05em) 50%, 0em calc(100% - 0.05em), 0.05em 100%, 50% calc(50% + 0.05em), calc(100% - 0.05em) 100%, 100% calc(100% - 0.05em), calc(50% + 0.05em) 50%, 100% 0.05em, calc(100% - 0.05em) 0%, 50% calc(50% - 0.05em)); }
}
.tex-bad { color: var(--bad); font-size: 0.9em; }
.img-missing { color: var(--muted); font-style: italic; font-size: 0.85em; }

.answers { display: grid; gap: 4px; margin-top: 12px; padding-top: 8px; border-top: 1px solid var(--line); }
.answer { display: flex; align-items: flex-start; gap: 10px; padding: 7px 10px; border: 1px solid transparent; border-radius: 6px; }
/* vòng tròn như nút chọn của Canvas; phương án đúng: vòng xanh có dấu ✓ */
.answer-mark {
  flex: none; display: inline-flex; align-items: center; justify-content: center; width: 18px; height: 18px; margin-top: 3px;
  border: 1.5px solid var(--line-strong); border-radius: 50%; font-size: 12px; font-weight: 700; line-height: 1;
}
.answer-text { flex: 1; min-width: 0; }
.answer-tag { flex: none; margin-left: auto; font-size: 12px; font-weight: 700; color: var(--ok); white-space: nowrap; padding-top: 2px; }
.answer.correct { background: var(--ok-bg); border-color: var(--ok-stroke); }
.answer.correct .answer-mark { background: var(--ok); border-color: var(--ok); color: #fff; }
@media (prefers-color-scheme: dark) { .answer.correct .answer-mark { color: #10121a; } }

.statements { display: grid; gap: 6px; margin-top: 12px; }
.stmt {
  display: grid; grid-template-columns: auto minmax(0, 1fr) auto; gap: 10px; align-items: baseline;
  padding: 6px 8px 6px 10px; border: 1px solid var(--line); border-radius: 6px; background: var(--card);
}
.stmt.missing { border-color: var(--bad-stroke); box-shadow: inset 3px 0 0 var(--bad-stroke); }
.stmt-letter { font-weight: 600; }
/* đáp án của ý: Đ xanh, S đỏ, chưa có: "?" viền đỏ */
.tf-key {
  align-self: center; display: inline-block; min-width: 36px; padding: 4px 8px; border-radius: 8px; text-align: center;
  font-weight: 700; color: #fff;
}
.tf-key.tf-d { background: var(--ok); }
.tf-key.tf-s { background: var(--bad); }
.tf-key.tf-none { color: var(--bad); background: transparent; border: 1.5px dashed var(--bad-stroke); }
@media (prefers-color-scheme: dark) { .tf-key.tf-d, .tf-key.tf-s { color: #10121a; } }

.sa { display: flex; flex-wrap: wrap; align-items: baseline; gap: 6px 10px; margin-top: 12px; }
.sa-label { font-weight: 600; }
.sa-answer {
  padding: 4px 10px; border-radius: 6px; font-weight: 700; color: var(--ok);
  background: var(--ok-bg); border: 1px solid var(--ok-stroke); overflow-wrap: anywhere;
}
.sa-answer.none { color: var(--bad); background: transparent; border: 1.5px dashed var(--bad-stroke); font-weight: 600; }
.sa-hint { color: var(--muted); font-size: 13px; }
.es-note { margin: 10px 0 0; color: var(--muted); font-size: 14px; }

/* ---------- 4. Thông tin quiz ---------- */
.form { display: grid; grid-template-columns: 112px minmax(0, 1fr); gap: 12px; align-items: start; }
.form .lbl { margin: 0; padding-top: 9px; }
.form .ctl > select, .form .ctl > input[type="text"] { width: 100%; }
.form .ctl .msg, .form .ctl .hint { margin-top: 6px; }
.time-check { white-space: nowrap; font-weight: 600; }
.time-row { display: flex; align-items: center; gap: 8px; }
.time-row input { width: 6.5em; }
.progress { margin-top: 14px; }
.progress progress { width: 100%; height: 10px; accent-color: var(--accent); }
.progress p { margin: 6px 0 0; font-size: 15px; }
#afterMsg { margin-top: 12px; }
.result-notes p { margin: 0 0 4px; font-size: 14px; color: var(--warn-text); }

/* ---------- Điện thoại ---------- */
@media (max-width: 560px) {
  .card { padding: 16px; border-radius: 12px; }
  .q-body { padding: 10px 12px 12px; }
  .q-head { padding: 7px 12px; }
  .form { grid-template-columns: 1fr; gap: 6px; }
  .form .lbl { padding-top: 6px; }
  .form .lbl:empty { display: none; }
  .answer { padding: 7px 6px; }
  .answer-tag { display: none; } /* điện thoại: vòng xanh có dấu ✓ là đủ */
  .stmt { gap: 8px; padding-left: 8px; }
  .tf-key { min-width: 32px; }
}