/* ระบบเช็คชื่อและส่งงาน — สีหมึกปากกาครู: น้ำเงินเขียน แดงตรวจ บนกระดาษสมุด */
:root{
  --ink:#17243b; --ink-2:#4a5870; --muted:#6b778c;
  --paper:#f5f7fa; --surface:#fff; --line:#d9dfe8; --line-2:#eef1f5;
  --blue:#1e5aa8; --blue-d:#164683; --blue-50:#eaf1fb;
  --red:#c4312b; --red-50:#fbecea;
  --present:#2f7d4a; --present-50:#e7f3eb;
  --late:#a8680f; --late-50:#fbf1e1;
  --leave:#6b5ba8; --leave-50:#efecf8;
  --absent:#c4312b; --absent-50:#fbecea;
  --r-sm:4px; --r:8px;
  --ui:'IBM Plex Sans Thai',system-ui,sans-serif;
  --body:'IBM Plex Sans Thai Looped','IBM Plex Sans Thai',system-ui,sans-serif;
}
*{box-sizing:border-box}
html{font-size:16px}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--body);line-height:1.65;-webkit-font-smoothing:antialiased}
h1,h2,h3,h4,button,.btn,.nav,.tabs,th,label,.tag,.chip,select,input{font-family:var(--ui)}
h1{font-size:1.75rem;line-height:1.25;margin:.2rem 0 .4rem;font-weight:600;letter-spacing:-.005em}
h2{font-size:1.25rem;margin:1.6rem 0 .7rem;font-weight:600}
h3{font-size:1.05rem;margin:0 0 .6rem;font-weight:600}
h4{font-size:.95rem;margin:1.2rem 0 .5rem}
a{color:var(--blue)} a:hover{color:var(--blue-d)}
p{margin:.3rem 0 .8rem}
code{font-family:var(--ui);background:var(--line-2);padding:.05em .35em;border-radius:3px;font-weight:600;letter-spacing:.06em}
code.big{font-size:1.3rem}
.muted{color:var(--muted)} .small{font-size:.85rem} .center{text-align:center} .right{justify-content:flex-end}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}
.over{color:var(--red)} .warn{color:var(--red);font-weight:600}
:focus-visible{outline:3px solid #7aa7e6;outline-offset:2px}

/* ---------- top bar ---------- */
.top{display:flex;align-items:center;gap:1.2rem;background:var(--ink);color:#fff;padding:.55rem 1.4rem;flex-wrap:wrap;position:sticky;top:0;z-index:10}
.brand{display:flex;align-items:center;gap:.6rem;color:#fff;text-decoration:none;font-family:var(--ui);font-weight:600}
.brand:hover{color:#fff}
.brand-mark{display:grid;place-items:center;width:30px;height:30px;border-radius:var(--r-sm);background:var(--present);font-size:1.05rem;box-shadow:inset 0 -3px 0 rgba(0,0,0,.18)}
.nav{display:flex;gap:.2rem;flex:1}
.nav a{color:#c9d3e4;text-decoration:none;padding:.35rem .75rem;border-radius:var(--r-sm);font-size:.95rem}
.nav a:hover{color:#fff;background:rgba(255,255,255,.07)}
.nav a.on{color:#fff;background:rgba(255,255,255,.13)}
.term-switch select{background:#24344f;color:#fff;border:1px solid #3a4b69;border-radius:var(--r-sm);padding:.3rem .5rem;font-size:.9rem}
.who{display:flex;align-items:center;gap:.6rem;font-size:.9rem;font-family:var(--ui)}
.who a{color:#fff;text-decoration:none} .who .logout{color:#9fb0cb}
.role{background:#2b3c5a;border-radius:3px;padding:0 .4rem;font-size:.78rem;color:#c9d3e4}

.main{max-width:1240px;margin:0 auto;padding:1.6rem 1.4rem 4rem}
.main-bare{min-height:100vh;display:grid;place-items:center;padding:2rem 1rem}

/* ---------- surfaces ---------- */
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--r);padding:1.2rem 1.3rem;margin-bottom:1rem}
.card-head{display:flex;justify-content:space-between;align-items:center;gap:1rem;flex-wrap:wrap;margin-bottom:.6rem}
.card-head h3{margin:0}
.page-head{display:flex;justify-content:space-between;align-items:flex-end;gap:1rem;flex-wrap:wrap;margin-bottom:1.1rem}
.page-head p{margin:0}
.split{display:grid;grid-template-columns:minmax(280px,360px) 1fr;gap:1rem;align-items:start}
.split-wide{grid-template-columns:minmax(260px,320px) minmax(0,1fr)}
.split>*{min-width:0}
.narrow{max-width:640px}
.scroll{overflow-x:auto}
.empty{color:var(--muted);text-align:center;padding:1.6rem 1rem}
.prose{max-width:72ch}

/* ---------- forms ---------- */
.form{display:flex;flex-direction:column;gap:.75rem}
label{display:flex;flex-direction:column;gap:.25rem;font-size:.9rem;color:var(--ink-2);font-weight:500}
input,select,textarea{font:inherit;font-size:1rem;color:var(--ink);background:#fff;border:1px solid #c5cedb;border-radius:var(--r-sm);padding:.5rem .65rem;width:100%}
textarea{font-family:var(--body);resize:vertical}
input:focus,select:focus,textarea:focus{border-color:var(--blue);outline:2px solid var(--blue-50)}
input[type=checkbox],input[type=radio]{width:auto}
label.check{flex-direction:row;align-items:center;gap:.5rem;font-weight:400;color:var(--ink)}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:.75rem}
.row3{display:grid;grid-template-columns:1fr 1fr 1fr;gap:.75rem;align-items:end}
.span2{grid-column:span 2}
.input-sm{padding:.3rem .5rem;font-size:.9rem;min-width:7rem}
.input-xs{padding:.2rem .35rem;width:3.4rem;text-align:center;font-size:.9rem}
.filters{display:flex;gap:.5rem;flex-wrap:wrap;margin-bottom:.8rem}
.filters input{flex:1;min-width:200px}
.filters select,.filters input{width:auto}
fieldset{border:0;padding:0;margin:0}
.dows{display:flex;gap:.4rem;flex-wrap:wrap}
.dows legend{font-size:.9rem;color:var(--ink-2);margin-bottom:.25rem;font-family:var(--ui)}
.dows label{flex-direction:row;align-items:center;gap:.25rem;border:1px solid var(--line);border-radius:var(--r-sm);padding:.2rem .5rem;font-weight:400}

.seg{display:flex;border:1px solid #c5cedb;border-radius:var(--r-sm);overflow:hidden}
.seg legend{font-size:.9rem;color:var(--ink-2);padding-bottom:.3rem;font-family:var(--ui)}
fieldset.seg{display:grid;grid-template-columns:repeat(auto-fit,minmax(0,1fr));border:0}
.seg label{flex-direction:row;justify-content:center;align-items:center;gap:.35rem;padding:.5rem;border:1px solid #c5cedb;margin-left:-1px;cursor:pointer;font-weight:500;color:var(--ink)}
.seg label:has(input:checked){background:var(--blue-50);border-color:var(--blue);position:relative;z-index:1}
.seg-revise:has(input:checked){background:var(--red-50)!important;border-color:var(--red)!important;color:var(--red)}
.seg-passed:has(input:checked){background:var(--present-50)!important;border-color:var(--present)!important;color:var(--present)}
.seg input{accent-color:var(--blue)}

/* ---------- buttons ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:.4rem;font-size:.95rem;font-weight:500;padding:.5rem 1rem;border-radius:var(--r-sm);border:1px solid #c5cedb;background:#fff;color:var(--ink);text-decoration:none;cursor:pointer;line-height:1.3;white-space:nowrap}
.btn:hover{border-color:var(--ink-2);color:var(--ink)}
.btn-primary{background:var(--blue);border-color:var(--blue);color:#fff}
.btn-primary:hover{background:var(--blue-d);border-color:var(--blue-d);color:#fff}
.btn-ghost{background:transparent;border-color:transparent;color:var(--ink-2)}
.btn-ghost:hover{background:var(--line-2);border-color:transparent}
.btn-danger{background:#fff;border-color:var(--red);color:var(--red)}
.btn-danger:hover{background:var(--red);color:#fff}
.btn-sm{padding:.3rem .7rem;font-size:.85rem}
.wide{width:100%}
.link{background:none;border:0;padding:0;color:var(--blue);cursor:pointer;font:inherit;font-size:.9rem}
.link.danger{color:var(--red)}
.actions{display:flex;gap:.5rem;flex-wrap:wrap;align-items:center}
.actions.center{justify-content:center}
form.inline{display:inline}
.row-actions{white-space:nowrap;text-align:right}
.row-actions > *{margin-left:.7rem;font-size:.9rem}

/* ---------- flash / tags ---------- */
.flash{padding:.65rem .9rem;border-radius:var(--r-sm);margin-bottom:1rem;border-left:4px solid;font-size:.95rem;background:#fff}
.flash-ok{border-color:var(--present);background:var(--present-50)}
.flash-err{border-color:var(--red);background:var(--red-50)}
.flash-warn{border-color:var(--late);background:var(--late-50)}
.tag{display:inline-block;font-size:.78rem;font-weight:500;padding:.05rem .5rem;border-radius:3px;border:1px solid;vertical-align:middle;white-space:nowrap}
.tag-pending{color:var(--blue);border-color:#b9cff0;background:var(--blue-50)}
.tag-revise{color:var(--red);border-color:#efc2bf;background:var(--red-50)}
.tag-passed{color:var(--present);border-color:#bddcc7;background:var(--present-50)}
.tag-missing{color:#fff;border-color:var(--red);background:var(--red)}
.tag-none{color:var(--muted);border-color:var(--line);background:var(--line-2)}
.score{font-family:var(--ui);font-weight:600;color:var(--red)}
.score.big{font-size:1.4rem;margin-left:.5rem}

/* ---------- attendance chips: หัวใจของระบบ ---------- */
.chip{display:inline-grid;place-items:center;width:1.7rem;height:1.7rem;border-radius:3px;font-size:.85rem;font-weight:600;line-height:1;border:1px solid transparent}
.chip-present{background:var(--present-50);color:var(--present);border-color:#bddcc7}
.chip-late{background:var(--late-50);color:var(--late);border-color:#ecd3a8}
.chip-leave{background:var(--leave-50);color:var(--leave);border-color:#d4cdef}
.chip-absent{background:var(--absent);color:#fff}
.chip-empty{color:#b3bccb;border:1px dashed #c9d1dd}
.chip-future{border:1px solid var(--line-2);background:transparent}
td .chip:not(.chip-future){width:1.7rem}
.legend{display:flex;flex-direction:column;gap:.45rem;font-size:.9rem}
.legend span{display:flex;align-items:center;gap:.5rem}
.summary-line{display:flex;gap:1rem;flex-wrap:wrap}
.summary-line span{display:flex;align-items:center;gap:.35rem;font-family:var(--ui);font-weight:600}

/* ---------- tables ---------- */
.tbl{width:100%;border-collapse:collapse;font-size:.93rem}
.tbl th{text-align:left;font-weight:500;color:var(--muted);font-size:.83rem;padding:.45rem .6rem;border-bottom:1px solid var(--line);white-space:nowrap}
.tbl td{padding:.5rem .6rem;border-bottom:1px solid var(--line-2);vertical-align:middle}
.tbl tr:last-child td{border-bottom:0}
.tbl tbody tr:hover td{background:#fafbfd}
.tbl tr.focus td{background:var(--blue-50)}
.num{text-align:right;font-variant-numeric:tabular-nums}
.c{text-align:center}
.att-grid,.grade-grid{font-size:.88rem}
.att-grid td,.att-grid th{padding:.3rem .25rem}
.att-grid .vcol{text-align:center;font-size:.75rem}
.att-grid .vcol a{color:var(--ink-2);text-decoration:none}
.sticky{position:sticky;left:0;background:#fff;z-index:1;white-space:nowrap;min-width:12rem;padding-right:.8rem!important;box-shadow:1px 0 0 var(--line-2)}
.grade-grid .gcol{text-align:center;min-width:5.5rem;white-space:normal;line-height:1.3}
.grade-grid .gcol a{display:block;color:var(--ink);text-decoration:none;font-size:.8rem}
.gcell{display:inline-block;min-width:2.6rem;padding:.15rem .35rem;border-radius:3px;text-decoration:none;font-family:var(--ui);font-weight:600;font-variant-numeric:tabular-nums;color:var(--ink)}
.gcell-none{color:#b3bccb}
.gcell-missing{background:var(--red);color:#fff}
.gcell-pending{background:var(--blue-50);color:var(--blue)}
.gcell-revise{background:var(--red-50);color:var(--red)}
.gcell-passed{color:var(--present)}
.bar{display:inline-block;width:70px;height:6px;background:var(--line-2);border-radius:3px;vertical-align:middle;margin-right:.4rem;overflow:hidden}
.bar span{display:block;height:100%;background:var(--present)}

/* ---------- mark buttons (session) ---------- */
.marks{display:inline-flex;gap:3px}
.mark{position:relative;cursor:pointer}
.mark input{position:absolute;opacity:0;inset:0;cursor:pointer}
.mark span{display:grid;place-items:center;width:2.1rem;height:2.1rem;border-radius:4px;border:1px solid var(--line);font-family:var(--ui);font-weight:600;color:var(--muted);background:#fff;transition:background .12s}
.mark input:focus-visible+span{outline:3px solid #7aa7e6;outline-offset:1px}
.mark-present input:checked+span{background:var(--present);border-color:var(--present);color:#fff}
.mark-late input:checked+span{background:var(--late);border-color:var(--late);color:#fff}
.mark-leave input:checked+span{background:var(--leave);border-color:var(--leave);color:#fff}
.mark-absent input:checked+span{background:var(--absent);border-color:var(--absent);color:#fff}
.mark-none input:checked+span{background:var(--line-2)}
.mark:hover span{border-color:var(--ink-2)}

.session-layout{display:grid;grid-template-columns:minmax(280px,380px) minmax(0,1fr);gap:1rem;align-items:start}
.code-panel{text-align:center;position:sticky;top:4.2rem}
.code-panel.is-open{background:var(--ink);color:#fff;border-color:var(--ink)}
.code-label{color:#9fb0cb;margin:0;font-family:var(--ui)}
.big-code{font-family:var(--ui);font-weight:700;font-size:clamp(2.6rem,4.6vw,3.6rem);letter-spacing:.08em;white-space:nowrap;line-height:1.1;margin:.2rem 0 .8rem;font-variant-numeric:tabular-nums}
.big-code span{display:inline-block;width:.3em}
#qr{display:inline-block;background:#fff;padding:10px;border-radius:var(--r-sm);line-height:0}
#qr svg{width:190px;height:190px;display:block}
.code-meta{color:#c9d3e4;font-family:var(--ui);margin:.8rem 0}
.code-meta strong{color:#fff;font-size:1.2rem}
.code-panel .btn{background:transparent;color:#fff;border-color:#4b5d7c}
.code-panel:not(.is-open) .btn-primary{background:var(--blue);border-color:var(--blue)}
.code-panel:not(.is-open) .btn{color:#fff}
.code-panel:not(.is-open) label{text-align:left}
.code-panel.fs{position:fixed;inset:0;z-index:100;border-radius:0;display:flex;flex-direction:column;justify-content:center;align-items:center}
.code-panel.fs .big-code{font-size:clamp(5rem,16vw,12rem)}
.code-panel.fs #qr svg{width:min(34vh,340px);height:min(34vh,340px)}

.code-input{font-family:var(--ui);font-size:2rem;text-align:center;letter-spacing:.3em;font-weight:600;padding:.4rem;text-transform:uppercase}
.checkin-box,.checkin-confirm{display:flex;flex-direction:column;gap:.7rem}
.checkin-confirm{max-width:420px;margin:2rem auto;text-align:center}

/* ---------- courses ---------- */
.courses{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:.9rem}
.course-card{display:flex;flex-direction:column;gap:.15rem;background:#fff;border:1px solid var(--line);border-left:5px solid var(--blue);border-radius:var(--r-sm);padding:.9rem 1rem;text-decoration:none;color:var(--ink)}
.course-card:hover{border-color:var(--ink-2);border-left-color:var(--blue-d);color:var(--ink)}
.c-code{font-family:var(--ui);font-weight:600;font-size:.9rem;color:var(--blue)}
.c-name{font-family:var(--ui);font-size:1.12rem;font-weight:600;line-height:1.35}
.c-meta{font-size:.87rem}
.c-stats{display:flex;gap:.8rem;margin-top:.5rem;font-size:.85rem;color:var(--ink-2);font-family:var(--ui);align-items:center}
.course-head .code{color:var(--blue)}
.tabs{display:flex;gap:.2rem;border-bottom:1px solid var(--line);margin-bottom:1rem;overflow-x:auto}
.tabs a{padding:.55rem .9rem;text-decoration:none;color:var(--ink-2);border-bottom:3px solid transparent;margin-bottom:-1px;white-space:nowrap}
.tabs a.on{color:var(--ink);border-bottom-color:var(--blue);font-weight:600}
.tabs-sm a{padding:.4rem .7rem;font-size:.9rem}
.count{font-size:.78rem;background:var(--line-2);border-radius:8px;padding:0 .4rem;color:var(--muted)}
.overview{display:grid;grid-template-columns:1fr minmax(260px,340px);gap:1rem;align-items:start}
.facts{display:flex;gap:2rem;flex-wrap:wrap;margin:0 0 .6rem}
.facts div{display:flex;flex-direction:column}
.facts dt{font-size:.83rem;color:var(--muted);font-family:var(--ui)}
.facts dd{margin:0;font-family:var(--ui);font-size:1.35rem;font-weight:600}
.joinbox{text-align:center}
.join-code{font-family:var(--ui);font-size:2.4rem;font-weight:700;letter-spacing:.18em;margin:.2rem 0;color:var(--blue)}
.join label{font-weight:600;color:var(--ink)}
.join-row{display:flex;gap:.5rem;margin-top:.4rem;max-width:420px}
.join-row input{text-transform:uppercase;letter-spacing:.15em;font-weight:600}

.todo,.asg-list{list-style:none;padding:0;margin:0;background:#fff;border:1px solid var(--line);border-radius:var(--r)}
.todo li,.asg-list li{display:flex;gap:.7rem;align-items:center;flex-wrap:wrap;padding:.7rem 1rem;border-bottom:1px solid var(--line-2)}
.todo li:last-child,.asg-list li:last-child{border-bottom:0}
.card .asg-list{border:0}
.due{margin-left:auto;font-size:.87rem;color:var(--ink-2);font-family:var(--ui)}
.due.over{color:var(--red)}

/* ---------- review ---------- */
.review-layout{display:grid;grid-template-columns:1fr;gap:1rem;align-items:start}
.review-layout.has-focus{grid-template-columns:minmax(0,1fr) minmax(320px,420px)}
.review-panel{position:sticky;top:4.2rem;max-height:calc(100vh - 5rem);overflow:auto;border-top:4px solid var(--red)}
.history{list-style:none;padding:0;margin:0}
.history li{border-left:2px solid var(--line);padding:.2rem 0 .9rem .9rem;position:relative}
.history li::before{content:"";position:absolute;left:-6px;top:.55rem;width:10px;height:10px;border-radius:50%;background:#fff;border:2px solid var(--blue)}
.h-head{display:flex;gap:.4rem;align-items:center;flex-wrap:wrap}
.h-link{display:inline-block;margin:.2rem .8rem .2rem 0;font-size:.92rem;word-break:break-all}
.h-review{background:var(--red-50);border-radius:var(--r-sm);padding:.5rem .7rem;margin-top:.4rem;font-size:.92rem}
.h-review strong{color:var(--red);font-family:var(--ui)}
.h-review p{margin:.3rem 0 0}
.danger-zone{border-color:#efc2bf}

/* ---------- auth ---------- */
.auth{display:grid;grid-template-columns:1.1fr 1fr;max-width:920px;width:100%;gap:2.5rem;align-items:center}
.auth-narrow{grid-template-columns:1fr;max-width:460px}
.auth-side h1{font-size:2.2rem;margin:1.2rem 0 .3rem}
.auth-side p{color:var(--ink-2)}
.auth-book{display:grid;grid-template-columns:repeat(7,2.2rem);gap:6px}
.auth-book .chip{width:2.2rem;height:2.2rem;font-size:1rem}
.auth-form{display:flex;flex-direction:column;gap:.85rem;padding:1.8rem}
.auth-form h2{margin:0 0 .3rem}
.auth-form .seg label{border-radius:0}

@media (max-width:900px){
  .split,.split-wide,.session-layout,.overview,.review-layout.has-focus,.auth{grid-template-columns:1fr}
  .code-panel,.review-panel{position:static;max-height:none}
  .auth-side{display:none}
  .nav{order:3;flex-basis:100%;overflow-x:auto}
  .term-switch{margin-left:auto}
  .who .role{display:none}
}
@media (max-width:560px){
  .main{padding:1rem .8rem 3rem}
  .row2,.row3{grid-template-columns:1fr}.span2{grid-column:auto}
  .top{padding:.5rem .8rem;gap:.6rem}
  .who a:first-child{display:none}
  .mark span{width:2rem;height:2rem}
  h1{font-size:1.45rem}
}
@media (prefers-reduced-motion:reduce){*{transition:none!important}}
@media print{.top,.actions,.tabs,.btn,form.filters{display:none!important}.card{border:0;padding:0}body{background:#fff}}