:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-2: #eef1f5;
  --text: #1b2430;
  --muted: #5d6b7c;
  --border: #d8dee6;
  --primary: #1f3a5f;
  --primary-text: #ffffff;
  --accent: #2f6fb3;
  --ok: #1e7b45;
  --ok-bg: #e3f4ea;
  --bad: #b3261e;
  --bad-bg: #fbe6e4;
  --warn: #8a5a00;
  --warn-bg: #fff3d6;
  --info: #1d5fa3;
  --info-bg: #e5effa;
  --radius: 12px;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #12161c; --surface: #1b2129; --surface-2: #242c36; --text: #e6ebf1;
    --muted: #9aa7b6; --border: #334050; --primary: #8fb4e3; --primary-text: #0e1620;
    --accent: #8fb4e3; --ok: #6fd39a; --ok-bg: #173325; --bad: #ff8a80; --bad-bg: #3a1c1a;
    --warn: #f3c66b; --warn-bg: #3a2e12; --info: #8fc1f5; --info-bg: #182a3e;
  }
}
:root[data-theme="dark"] {
  --bg: #12161c; --surface: #1b2129; --surface-2: #242c36; --text: #e6ebf1;
  --muted: #9aa7b6; --border: #334050; --primary: #8fb4e3; --primary-text: #0e1620;
  --accent: #8fb4e3; --ok: #6fd39a; --ok-bg: #173325; --bad: #ff8a80; --bad-bg: #3a1c1a;
  --warn: #f3c66b; --warn-bg: #3a2e12; --info: #8fc1f5; --info-bg: #182a3e;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Sarabun", "Noto Sans Thai", "Leelawadee UI", system-ui, sans-serif;
  font-size: 17px;
  line-height: 1.65;
}
a { color: var(--accent); }
h1, h2, h3 { line-height: 1.35; margin: 0 0 .5rem; }
h1 { font-size: 1.35rem; }
h2 { font-size: 1.15rem; }
h3 { font-size: 1.02rem; }
p { margin: 0 0 .75rem; }

.topbar {
  position: sticky; top: 0; z-index: 10;
  display: flex; align-items: center; justify-content: space-between; gap: 8px;
  padding: 10px 16px;
  background: var(--primary); color: var(--primary-text);
}
.topbar a { color: var(--primary-text); text-decoration: none; }
.brand { font-weight: 700; white-space: nowrap; }
.topnav { display: flex; align-items: center; gap: 12px; font-size: .95rem; }
.topnav a { white-space: nowrap; }
.icon-btn { background: none; border: 0; font-size: 1.1rem; cursor: pointer; color: inherit; padding: 4px; }

.container { max-width: 760px; margin: 0 auto; padding: 16px 16px 96px; }
.muted { color: var(--muted); }
.small { font-size: .88rem; }

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 12px;
}
.card-link { display: block; color: inherit; text-decoration: none; }
.card-link:active { background: var(--surface-2); }
.row { display: flex; align-items: center; justify-content: space-between; gap: 10px; flex-wrap: wrap; }
.stack > * + * { margin-top: 8px; }

.badge {
  display: inline-block; padding: 1px 8px; border-radius: 999px;
  font-size: .78rem; background: var(--surface-2); color: var(--muted); white-space: nowrap;
}
.badge.ok { background: var(--ok-bg); color: var(--ok); }
.badge.bad { background: var(--bad-bg); color: var(--bad); }
.badge.warn { background: var(--warn-bg); color: var(--warn); }
.badge.info { background: var(--info-bg); color: var(--info); }
/* ความยาก: สีตามความหมายเดียวกันทั้งเว็บ (เขียว ง่าย · เหลือง กลาง · แดง ยาก) และมีคำกำกับเสมอ */
.badge.diff-1 { background: var(--ok-bg); color: var(--ok); }
.badge.diff-2 { background: var(--warn-bg); color: var(--warn); }
.badge.diff-3 { background: var(--bad-bg); color: var(--bad); }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  min-height: 44px; padding: 8px 16px;
  border-radius: 10px; border: 1px solid var(--border);
  background: var(--surface); color: var(--text);
  font: inherit; font-weight: 600; cursor: pointer; text-decoration: none;
}
.btn.primary { background: var(--primary); color: var(--primary-text); border-color: var(--primary); }
.btn.block { width: 100%; }
.btn:disabled { opacity: .5; cursor: default; }
.btn-row { display: flex; gap: 8px; flex-wrap: wrap; }
.btn-row .btn { flex: 1 1 140px; }

select, input[type="number"] {
  font: inherit; min-height: 44px; padding: 6px 10px; width: 100%;
  border-radius: 10px; border: 1px solid var(--border); background: var(--surface); color: var(--text);
}
label { display: block; font-weight: 600; margin-bottom: 4px; }

/* quiz */
.quiz-head {
  position: sticky; top: 52px; z-index: 5;
  display: flex; align-items: center; justify-content: space-between; gap: 8px;
  background: var(--bg); padding: 8px 0; margin-bottom: 8px;
  border-bottom: 1px solid var(--border);
}
.timer { font-variant-numeric: tabular-nums; font-weight: 700; }
.timer.low { color: var(--bad); }
.qtext { font-size: 1.05rem; white-space: pre-wrap; margin-bottom: 12px; }
.choices { display: grid; gap: 8px; }
.choice {
  display: flex; gap: 10px; align-items: flex-start; text-align: left;
  width: 100%; min-height: 48px; padding: 10px 12px;
  border: 1.5px solid var(--border); border-radius: 10px;
  background: var(--surface); color: var(--text); font: inherit; cursor: pointer;
}
.choice .letter { font-weight: 700; min-width: 1.4em; }
.choice.picked { border-color: var(--accent); background: var(--surface-2); }
.choice.correct { border-color: var(--ok); background: var(--ok-bg); }
.choice.wrong { border-color: var(--bad); background: var(--bad-bg); }
.choice:disabled { cursor: default; }

.explain { margin-top: 14px; }
.verdict { display: flex; align-items: center; justify-content: space-between; gap: 8px;
  margin: -14px -16px 12px; padding: 10px 16px; border-radius: var(--radius) var(--radius) 0 0;
  background: var(--surface-2); font-size: 1.05rem; }
.verdict.ok { background: var(--ok-bg); color: var(--ok); }
.verdict.bad { background: var(--bad-bg); color: var(--bad); }
.why-bad { color: var(--muted); }
.q-meta { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; font-size: .88rem; color: var(--muted); }
.q-meta .q-topic { flex: 1; min-width: 0; }
.q-meta .bm { margin-left: auto; }
.progress { margin-top: 8px; height: 6px; }
.progress > span { background: var(--ok); }
.explain h3 { margin-top: 10px; }
.why-list { list-style: none; padding: 0; margin: 0; }
.why-list li { padding: 6px 0; border-top: 1px dashed var(--border); }
.learn { background: var(--info-bg); border-left: 4px solid var(--info); border-radius: 10px; padding: 10px 12px; margin: 10px 0; }
.learn h3 { margin-top: 0; }
.learn p { margin: 0; }
.tip { background: var(--warn-bg); color: var(--text); border-left: 4px solid var(--warn); border-radius: 10px; padding: 10px 12px; margin: 0 0 12px; }
.lawref { font-size: .9rem; color: var(--muted); margin-top: 8px; }

.qtable { width: 100%; border-collapse: collapse; margin: 8px 0 12px; font-size: .95rem; }
.qtable th, .qtable td { border: 1px solid var(--border); padding: 6px 8px; text-align: center; }
.qtable th { background: var(--surface-2); }
.table-wrap { overflow-x: auto; }

.navgrid { display: grid; grid-template-columns: repeat(auto-fill, minmax(42px, 1fr)); gap: 6px; margin-top: 12px; }
.navgrid button {
  min-height: 40px; border-radius: 8px; border: 1px solid var(--border);
  background: var(--surface); color: var(--text); font: inherit; cursor: pointer;
}
.navgrid button.answered { background: var(--surface-2); border-color: var(--accent); }
.navgrid button.current { outline: 2px solid var(--accent); }
.navgrid button.ok { background: var(--ok-bg); border-color: var(--ok); }
.navgrid button.bad { background: var(--bad-bg); border-color: var(--bad); }

.bottom-bar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 8;
  background: var(--surface); border-top: 1px solid var(--border);
  padding: 8px 16px calc(8px + env(safe-area-inset-bottom));
}
.bottom-bar .inner { max-width: 760px; margin: 0 auto; display: flex; gap: 8px; }
.bottom-bar .btn { flex: 1; }

.score-big { font-size: 2rem; font-weight: 700; }
.bar { height: 8px; background: var(--surface-2); border-radius: 999px; overflow: hidden; position: relative; }
.bar > span { display: block; height: 100%; background: var(--accent); }
.bar > i { position: absolute; top: -2px; bottom: -2px; width: 2px; background: var(--text); opacity: .6; }

.chart { width: 100%; height: auto; display: block; }
.chart text { fill: var(--muted); font-size: 11px; font-family: inherit; }
.chart .grid { stroke: var(--border); stroke-width: 1; }
.chart .line { fill: none; stroke: var(--accent); stroke-width: 2; }
.chart .dot { fill: var(--accent); }
.chart .pass { stroke: var(--ok); stroke-dasharray: 4 4; stroke-width: 1.5; }

.bm { background: none; border: 0; font-size: 1.35rem; line-height: 1; cursor: pointer; padding: 4px; color: var(--warn); }
.notice { background: var(--warn-bg); border-radius: 10px; padding: 10px 12px; font-size: .92rem; margin-bottom: 12px; }

/* คะแนนรายด้าน: summary = ด้าน, เปิดแล้วเห็นหัวข้อย่อย */
.group { border-top: 1px solid var(--border); padding: 8px 0; }
.group summary { cursor: pointer; list-style: none; display: grid; gap: 4px; }
.group summary::-webkit-details-marker { display: none; }
.group summary .bar { display: block; }
.sub-list { list-style: none; margin: 8px 0 0; padding: 0 0 0 12px; display: grid; gap: 4px; }
.bad-text { color: var(--bad); }

/* หน้าประกาศรับสมัคร: summary เป็นปุ่ม "ดูรายละเอียด" */
.recruit-more > summary { list-style: none; text-align: center; }
.recruit-more > summary::-webkit-details-marker { display: none; }
.recruit-more[open] > summary { margin-bottom: 8px; }
.recruit-more ul { padding-left: 20px; }
.backup { width: 100%; font: inherit; font-size: .8rem; padding: 8px; border-radius: 10px; border: 1px solid var(--border); background: var(--surface-2); color: var(--text); margin-bottom: 8px; }

/* คอม: แสดงคีย์ลัดเฉพาะเครื่องที่มีเมาส์ · จอกว้างหน้าแรกเรียงการ์ดสนาม 2 คอลัมน์ */
.kbd-hint { display: none; margin: 0 0 8px; }
@media (hover: hover) and (pointer: fine) and (min-width: 700px) { .kbd-hint { display: block; } }
@media (min-width: 1100px) {
  .container.wide { max-width: 1100px; }
  .exam-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-bottom: 12px; }
  .exam-grid .card { margin-bottom: 0; }
}

/* แผนอ่าน */
.tasks { list-style: none; margin: 0; padding: 0; display: grid; gap: 6px; }
.task { display: flex; justify-content: space-between; align-items: flex-start; gap: 8px; padding: 8px 0; border-top: 1px dashed var(--border); }
.task label { display: flex; gap: 8px; align-items: flex-start; font-weight: 400; margin: 0; flex: 1; cursor: pointer; }
.task input { width: 20px; height: 20px; margin-top: 3px; flex: none; accent-color: var(--ok); }
.task.done label span { color: var(--muted); text-decoration: line-through; }
.task-meta { display: flex; flex-direction: column; align-items: flex-end; gap: 2px; white-space: nowrap; }
.task-meta a { text-decoration: none; }
.plan-card { border-left: 4px solid var(--info); }
.count { display: flex; gap: 14px; align-items: center; }
.count-n { min-width: 64px; text-align: center; font-size: 1.8rem; font-weight: 700; line-height: 1.1; color: var(--info); }
.count-n small { display: block; font-size: .75rem; font-weight: 600; color: var(--muted); }
.stat-row { display: grid; grid-template-columns: repeat(3, 1fr); text-align: center; gap: 8px; }
.stat-row .score-big { font-size: 1.6rem; }
.week td { text-align: left; vertical-align: top; }
.week td:last-child { text-align: center; }
.week tr.light td { background: var(--ok-bg); }
.week tr.today td { outline: 2px solid var(--info); outline-offset: -2px; }
.routine { margin: 0; padding-left: 20px; display: grid; gap: 6px; }
.book summary { cursor: pointer; list-style: none; }
.book summary::-webkit-details-marker { display: none; }
.book summary b::after { content: ' ▾'; color: var(--muted); }
.book ol { margin: 8px 0 0; padding-left: 20px; }
.clip-list { margin: 8px 0 0; padding-left: 18px; display: grid; gap: 4px; }
.clip-list a { text-decoration: none; }