/* ============================================================
   Classwork Hub — styles.css
   ธีม: Neo Brutalism
   - border หนา 3px สีดำทุก component
   - offset shadow สี (ไม่เบลอ) เช่น 4px 4px 0 #000
   - มุมแหลม (border-radius: 0-4px)
   - สีสด: ฟ้า #0066FF, เขียว #00D26A, เหลือง #FFDE59, ชมพู #FF6B9D, แดง #FF3333
   - ตัวหนา คอนทราสต์สูง
   ============================================================ */

:root{
  --primary:#0066FF; --primary-dark:#0044CC; --on-primary:#fff;
  --secondary:#00D26A; --on-secondary:#000;
  --accent:#FF6B9D; --accent-dark:#E0527F; --on-accent:#000;
  --yellow:#FFDE59; --neon:#00FF88;
  --bg:#FFFFFF; --fg:#000000;
  --card:#FFFFFF; --card-fg:#000000;
  --muted:#F0F0F0; --muted-fg:#555;
  --border:#000000;
  --destructive:#FF3333; --on-destructive:#000;
  --success:#00D26A; --success-bg:#E6FFF0;
  --warn:#FFAA00; --warn-bg:#FFF5DD;
  --info:#0066FF; --info-bg:#E6F0FF;
  --rose:#FF6B9D; --rose-bg:#FFE6F0;
  --ring:#0066FF;
  --radius:4px;
  --border-w:3px;
  --shadow:4px 4px 0 #000;
  --shadow-hover:6px 6px 0 #000;
  --shadow-active:2px 2px 0 #000;
  --shadow-sm:2px 2px 0 #000;
}
*{box-sizing:border-box; margin:0; padding:0}
html{scroll-behavior:smooth}
body{font-family:'Prompt',sans-serif; background:var(--bg); color:var(--fg); min-height:100vh;
  background-image:none;}
h1,h2,h3,h4{font-family:'Mitr',sans-serif; line-height:1.3; font-weight:900}
button{font-family:inherit}
:focus-visible{outline:3px solid var(--primary); outline-offset:2px}
::selection{background:var(--yellow); color:#000}

/* ---------- Header ---------- */
header{position:sticky; top:0; z-index:50; background:#fff;
  border-bottom:var(--border-w) solid #000; box-shadow:0 4px 0 #000;}
.header-in{max-width:1080px; margin:0 auto; padding:12px 16px; display:flex; align-items:center; gap:12px; flex-wrap:wrap}
.logo{display:flex; align-items:center; gap:10px; cursor:pointer; user-select:none}
.logo-badge{width:46px; height:46px; border-radius:2px; background:var(--primary);
  border:var(--border-w) solid #000; box-shadow:var(--shadow-sm);
  display:flex; align-items:center; justify-content:center; color:#fff;}
.logo h1{font-size:20px; color:#000; text-transform:uppercase; letter-spacing:1px}
.logo small{display:block; font-family:'Prompt'; font-size:11px; color:var(--muted-fg); font-weight:400}
nav{display:flex; gap:6px; flex-wrap:wrap; margin-left:auto}
.nav-tab{border:var(--border-w) solid #000; background:var(--muted); padding:9px 14px; border-radius:2px;
  font-size:14px; font-weight:700; color:#000; cursor:pointer;
  display:flex; align-items:center; gap:7px; box-shadow:var(--shadow-sm);
  transition:transform .08s, box-shadow .08s}
.nav-tab:hover{transform:translate(-1px,-1px); box-shadow:5px 5px 0 #000}
.nav-tab:active{transform:translate(1px,1px); box-shadow:var(--shadow-active)}
.nav-tab.active{background:var(--primary); color:#fff; box-shadow:var(--shadow)}
.nav-tab svg{width:18px; height:18px}
.role-switch{display:flex; background:var(--muted); border:var(--border-w) solid #000;
  border-radius:2px; padding:4px; box-shadow:var(--shadow-sm)}
.role-switch button{border:2px solid transparent; background:transparent; padding:7px 14px;
  border-radius:2px; cursor:pointer; font-size:13px; font-weight:700; color:var(--muted-fg)}
.role-switch button.active{background:#fff; color:#000; border-color:#000; box-shadow:var(--shadow-sm)}

/* ---------- Layout ---------- */
main{max-width:1080px; margin:0 auto; padding:22px 16px 60px}
.screen{display:none; animation:fadeIn .1s ease}
.screen.active{display:block}
@keyframes fadeIn{from{opacity:0} to{opacity:1}}
.page-title{font-size:24px; margin-bottom:4px; text-transform:uppercase; letter-spacing:0.5px}
.page-sub{color:var(--muted-fg); font-size:14px; margin-bottom:18px}

/* ---------- Cards (Neo Brutalism) ---------- */
.card{background:var(--card); border-radius:var(--radius);
  border:var(--border-w) solid #000; box-shadow:var(--shadow); overflow:hidden}
.card-pad{padding:18px}
.card-hover{transition:transform .08s ease, box-shadow .08s ease}
.card-hover:hover{transform:translate(-2px,-2px); box-shadow:var(--shadow-hover)}
.card-hover:active{transform:translate(1px,1px); box-shadow:var(--shadow-active)}

/* ---------- Bento Grid ---------- */
.bento{display:grid; grid-template-columns:repeat(auto-fill, minmax(255px, 1fr)); gap:16px; align-items:stretch}
@media(min-width:1100px){ .bento .span-2{grid-column:span 2} }
.bento .assign-item{flex-direction:column; padding:18px; height:100%}
.bento .assign-ico{width:44px; height:44px; margin-bottom:8px; border-radius:2px;
  border:var(--border-w) solid #000}
.bento .assign-ico svg{width:22px; height:22px}
.bento .assign-desc{-webkit-line-clamp:3}
.bento .assign-meta{margin-top:10px}
/* ไทล์ "สร้างใบงาน" (เส้นประ) */
.tile-add{display:flex; flex-direction:column; align-items:center; justify-content:center; gap:8px;
  min-height:150px; border:3px dashed #000; border-radius:var(--radius); background:transparent;
  color:#000; cursor:pointer; font-size:14px; font-weight:700; font-family:'Mitr'}
.tile-add:hover{background:var(--yellow); border-style:solid; transform:translate(-2px,-2px);
  box-shadow:var(--shadow-hover)}
.tile-add:active{transform:translate(1px,1px); box-shadow:var(--shadow-active)}
.tile-add svg{width:26px; height:26px}
/* ไทล์เลือกใบงานในหน้าตรวจงาน */
.tile-select{border:var(--border-w) solid #000; background:#fff; border-radius:var(--radius);
  padding:14px 16px; cursor:pointer; font-size:14px; font-weight:700; font-family:'Mitr';
  color:#000; text-align:left; box-shadow:var(--shadow);
  display:flex; align-items:center; justify-content:space-between; gap:8px;
  transition:transform .08s ease, box-shadow .08s ease}
.tile-select:hover{transform:translate(-2px,-2px); box-shadow:var(--shadow-hover)}
.tile-select:active{transform:translate(1px,1px); box-shadow:var(--shadow-active)}
.tile-select.selected{background:var(--primary); color:#fff; box-shadow:var(--shadow)}
.tile-select .badge{background:var(--destructive); color:#000; border-radius:2px;
  border:2px solid #000; padding:2px 10px; font-size:12px; font-family:'Prompt'; font-weight:700}
.tile-select.selected .badge{background:var(--yellow); color:#000; border-color:#000}

/* ---------- Buttons ---------- */
.btn{border:var(--border-w) solid #000; border-radius:2px; padding:10px 18px;
  font-size:14px; font-weight:700; cursor:pointer;
  display:inline-flex; align-items:center; gap:7px;
  box-shadow:var(--shadow-sm);
  transition:transform .08s ease, box-shadow .08s ease}
.btn:active{transform:translate(1px,1px); box-shadow:var(--shadow-active)}
.btn svg{width:17px; height:17px}
.btn-primary{background:var(--primary); color:#fff}
.btn-primary:hover{background:var(--primary-dark); transform:translate(-1px,-1px); box-shadow:4px 4px 0 #000}
.btn-accent{background:var(--accent); color:#000}
.btn-accent:hover{background:var(--accent-dark); transform:translate(-1px,-1px); box-shadow:4px 4px 0 #000}
.btn-soft{background:var(--muted); color:#000}
.btn-soft:hover{background:#E0E0E0}
.btn-success{background:var(--secondary); color:#000}
.btn-success:hover{background:#00B85C; transform:translate(-1px,-1px); box-shadow:4px 4px 0 #000}
.btn-danger{background:var(--destructive); color:#000}
.btn-danger:hover{background:#E02020; transform:translate(-1px,-1px); box-shadow:4px 4px 0 #000}
.btn-ghost{background:transparent; color:var(--muted-fg); box-shadow:none; border:2px solid #000}
.btn-ghost:hover{background:var(--muted)}
.btn:disabled{opacity:.4; cursor:not-allowed; transform:none!important; box-shadow:none!important}

/* ---------- Forms ---------- */
.field{margin-bottom:14px}
.field label{display:block; font-size:13px; font-weight:700; margin-bottom:6px; color:#000}
.input,.textarea,.select{width:100%; border:var(--border-w) solid #000; border-radius:2px;
  padding:10px 13px; font-family:inherit; font-size:14px; background:#fff; color:#000;
  box-shadow:var(--shadow-sm)}
.input:focus,.textarea:focus,.select:focus{outline:none; border-color:var(--primary);
  box-shadow:var(--shadow-sm), inset 0 0 0 2px var(--primary)}
.textarea{resize:vertical; min-height:90px}
.row{display:flex; gap:12px; flex-wrap:wrap}
.row>*{flex:1; min-width:140px}
.hint{font-size:12px; color:var(--muted-fg); margin-top:5px}
.file-drop{border:3px dashed #000; border-radius:var(--radius); padding:16px; text-align:center;
  cursor:pointer; color:#000; font-size:13px; font-weight:700; background:var(--muted);
  box-shadow:var(--shadow-sm)}
.file-drop:hover{border-color:var(--primary); background:var(--info-bg)}
.file-drop.has-file{border-color:var(--secondary); background:var(--success-bg); color:#000}

/* ---------- Chips / badges ---------- */
.chip{display:inline-flex; align-items:center; gap:5px; padding:3px 10px; border-radius:2px;
  font-size:12px; font-weight:700; border:2px solid #000}
.chip svg{width:13px; height:13px}
.chip-indigo{background:var(--info-bg); color:var(--info)}
.chip-rose{background:var(--rose-bg); color:var(--accent)}
.chip-green{background:var(--success-bg); color:#006633}
.chip-amber{background:var(--warn-bg); color:#995500}
.chip-gray{background:var(--muted); color:#000}
.chip-red{background:#FFE0E0; color:#CC0000}

/* ---------- Feed (Facebook style) ---------- */
.feed-wrap{max-width:640px; margin:0 auto}
.post{background:#fff; border-radius:var(--radius); border:var(--border-w) solid #000;
  box-shadow:var(--shadow); margin-bottom:18px; transition:transform .08s, box-shadow .08s}
.post:hover{transform:translate(-1px,-1px); box-shadow:var(--shadow-hover)}
.post-head{display:flex; align-items:center; gap:12px; padding:14px 16px 10px}
.avatar{width:46px; height:46px; border-radius:2px; flex-shrink:0; border:var(--border-w) solid #000;
  display:flex; align-items:center; justify-content:center; overflow:hidden;
  color:#000; font-family:'Mitr'; font-weight:700; font-size:18px;
  background:var(--yellow); box-shadow:var(--shadow-sm)}
.avatar img{width:100%; height:100%; object-fit:cover; display:block}
.avatar.clickable{cursor:pointer; transition:transform .1s}
.avatar.clickable:hover{transform:scale(1.08)}
.avatar.alt1{background:var(--accent)}
.avatar.alt2{background:var(--secondary)}
.avatar.alt3{background:#C084FC}
.avatar-preview-box{display:flex; align-items:center; gap:14px; padding:12px; border:2px solid #000; background:var(--muted); border-radius:2px; margin-bottom:14px}
.avatar-grid{display:grid; grid-template-columns:repeat(auto-fill, minmax(62px, 1fr)); gap:10px; max-height:280px; overflow-y:auto; padding:6px 2px}
.avatar-option{width:100%; aspect-ratio:1/1; border:2px solid #000; border-radius:2px; display:flex; align-items:center; justify-content:center; cursor:pointer; background:#fff; font-size:28px; transition:transform .08s, box-shadow .08s; box-shadow:2px 2px 0 #000; overflow:hidden}
.avatar-option:hover{transform:translate(-2px,-2px); box-shadow:4px 4px 0 #000; background:var(--yellow)}
.avatar-option.selected{border:3px solid var(--primary); background:#E0E7FF; transform:translate(-2px,-2px); box-shadow:4px 4px 0 #000}
.avatar-option img{width:100%; height:100%; object-fit:cover; display:block}
.post-meta{flex:1; min-width:0}
.post-author{font-family:'Mitr'; font-weight:700; font-size:14.5px; color:#000}
.post-time{font-size:12px; color:var(--muted-fg)}
.post-type{margin-right:auto}
.post-body{padding:2px 16px 12px; font-size:14.5px; line-height:1.7; white-space:pre-wrap; word-break:break-word}
.post-body .post-title{font-family:'Mitr'; font-weight:700; font-size:16px; margin-bottom:6px; color:#000}
.post-media{border-top:var(--border-w) solid #000; border-bottom:var(--border-w) solid #000}
.post-media img{width:100%; display:block; max-height:420px; object-fit:cover}
.post-media video{width:100%; display:block; max-height:420px; background:#000}
.video-frame{position:relative; padding-top:56.25%; background:#000}
.video-frame iframe{position:absolute; inset:0; width:100%; height:100%; border:none}
.post-actions{display:flex; padding:4px 8px; border-top:2px solid #000}
.post-actions button{flex:1; display:flex; align-items:center; justify-content:center; gap:8px;
  border:none; background:none; padding:10px; border-radius:0; cursor:pointer; color:#000;
  font-size:13.5px; font-weight:700; transition:background .08s}
.post-actions button:hover{background:var(--yellow)}
.post-actions button.liked{color:var(--accent)}
.post-actions svg{width:18px; height:18px}
.comments{padding:8px 16px 14px; border-top:2px solid #000}
.comment-item{display:flex; gap:9px; margin:9px 0}
.comment-item .avatar{width:32px; height:32px; font-size:13px; box-shadow:var(--shadow-sm)}
.comment-bubble{background:var(--muted); border:2px solid #000; border-radius:2px;
  padding:8px 12px; flex:1; box-shadow:2px 2px 0 #000}
.comment-name{font-weight:700; font-size:12.5px; color:var(--primary)}
.comment-text{font-size:13.5px; margin-top:2px; word-break:break-word}
.comment-form{display:flex; gap:8px; align-items:center; margin-top:6px}
.comment-form input{flex:1}

/* ---------- Hyperlink & Link Preview Card ---------- */
.post-link {
  color: var(--primary);
  font-weight: 700;
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
  word-break: break-all;
  transition: background .12s;
}
.post-link:hover {
  background: var(--yellow);
  color: #000;
}

.link-preview-card {
  display: block;
  margin: 8px 16px 14px;
  border: 2px solid #000;
  border-radius: 2px;
  background: #fff;
  text-decoration: none;
  color: inherit;
  overflow: hidden;
  box-shadow: 3px 3px 0 #000;
  transition: transform .08s, box-shadow .08s;
}
.link-preview-card:hover {
  transform: translate(-2px, -2px);
  box-shadow: 5px 5px 0 #000;
  background: var(--muted);
}
.link-preview-img {
  width: 100%;
  max-height: 220px;
  overflow: hidden;
  border-bottom: 2px solid #000;
  background: #f0f0f0;
}
.link-preview-img img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  display: block;
}
.link-preview-info {
  padding: 12px 14px;
}
.link-preview-domain {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  font-weight: 700;
  color: var(--muted-fg);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 4px;
}
.link-preview-domain img {
  width: 16px;
  height: 16px;
  border-radius: 2px;
}
.link-preview-title {
  font-family: 'Mitr';
  font-weight: 700;
  font-size: 15px;
  line-height: 1.4;
  color: #000;
  margin-bottom: 4px;
}
.link-preview-desc {
  font-size: 13px;
  color: var(--muted-fg);
  line-height: 1.5;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ---------- Assignment tiles ---------- */
.assign-item{display:flex; gap:14px; align-items:flex-start; padding:16px; cursor:pointer}
.assign-item:hover{background:var(--yellow)}
.assign-ico{width:46px; height:46px; border-radius:2px; flex-shrink:0;
  border:var(--border-w) solid #000; display:flex; align-items:center; justify-content:center; color:#000}
.assign-ico svg{width:23px; height:23px}
.assign-main{flex:1; min-width:0}
.assign-title{font-family:'Mitr'; font-weight:700; font-size:15.5px; line-height:1.4}
.assign-meta{display:flex; gap:8px; flex-wrap:wrap; margin-top:6px; align-items:center}
.assign-desc{font-size:13.5px; color:var(--muted-fg); margin-top:6px; display:-webkit-box;
  -webkit-line-clamp:2; -webkit-box-orient:vertical; overflow:hidden}

/* ---------- Detail / grading ---------- */
.detail-grid{display:grid; grid-template-columns:1fr; gap:18px}
@media(min-width:900px){.detail-grid{grid-template-columns:1fr 360px}}
.info-list{display:flex; flex-direction:column; gap:10px}
.info-row{display:flex; gap:10px; align-items:flex-start; font-size:14px}
.info-row svg{width:18px; height:18px; color:var(--primary); flex-shrink:0; margin-top:2px}
.sub-card{border:var(--border-w) solid #000; border-radius:var(--radius); padding:14px;
  margin-bottom:12px; background:#fff; box-shadow:var(--shadow-sm)}
.sub-head{display:flex; align-items:center; gap:10px; margin-bottom:8px; flex-wrap:wrap}
.sub-body{font-size:14px; line-height:1.6; margin:6px 0}
.sub-file{display:inline-flex; align-items:center; gap:7px; background:var(--info-bg);
  border:2px solid #000; padding:7px 12px; border-radius:2px; font-size:13px; font-weight:700;
  color:var(--primary); cursor:pointer; text-decoration:none; box-shadow:2px 2px 0 #000}
.sub-file:hover{background:var(--yellow)}
.grade-grid{display:grid; grid-template-columns:90px 1fr; gap:10px; margin-top:10px; align-items:start}
.score-input{width:100%; text-align:center; font-weight:900; font-size:16px;
  border:var(--border-w) solid #000; border-radius:2px; box-shadow:var(--shadow-sm)}
.score-input::-webkit-inner-spin-button{opacity:1}
.saved-flash{color:var(--success); font-size:12.5px; font-weight:700; display:flex; align-items:center; gap:4px}
@media(min-width:900px){ .submissions-2col{columns:2; column-gap:16px} .submissions-2col .sub-card{break-inside:avoid} }

/* ---------- Stats ---------- */
.stats{display:grid; grid-template-columns:repeat(auto-fit,minmax(150px,1fr)); gap:14px; margin-bottom:20px}
.stat{text-align:center; padding:16px 12px; transition:transform .08s, box-shadow .08s}
.stat:hover{transform:translate(-2px,-2px); box-shadow:var(--shadow-hover)}
.stat-num{font-family:'Mitr'; font-size:28px; font-weight:900; color:var(--primary)}
.stat-num.green{color:#006633} .stat-num.amber{color:#995500} .stat-num.rose{color:var(--accent)}
.stat-label{font-size:12.5px; color:var(--muted-fg); margin-top:2px}

/* ---------- Modal ---------- */
.overlay{position:fixed; inset:0; background:rgba(0,0,0,.5); z-index:100;
  display:none; align-items:flex-start; justify-content:center; padding:24px 14px; overflow-y:auto}
.overlay.show{display:flex}
.modal{background:#fff; border-radius:var(--radius); max-width:620px; width:100%;
  box-shadow:8px 8px 0 #000; border:var(--border-w) solid #000; animation:popIn .1s ease}
@keyframes popIn{from{opacity:0; transform:translate(-4px,-4px)} to{opacity:1; transform:none}}
.modal-head{display:flex; align-items:center; justify-content:space-between; padding:16px 20px;
  border-bottom:var(--border-w) solid #000}
.modal-head h3{font-size:17px}
.modal-body{padding:20px}
.modal-foot{padding:0 20px 20px; display:flex; gap:10px; justify-content:flex-end; flex-wrap:wrap}
.icon-btn{border:var(--border-w) solid #000; background:var(--muted); width:34px; height:34px;
  border-radius:2px; cursor:pointer; display:flex; align-items:center; justify-content:center;
  color:#000; box-shadow:2px 2px 0 #000; transition:transform .08s}
.icon-btn:hover{background:var(--yellow); transform:translate(-1px,-1px); box-shadow:3px 3px 0 #000}
.icon-btn:active{transform:translate(1px,1px); box-shadow:1px 1px 0 #000}
.icon-btn svg{width:18px; height:18px}

/* ---------- Toast ---------- */
#toast{position:fixed; bottom:22px; left:50%; transform:translateX(-50%) translateY(80px);
  background:#000; color:#fff; padding:11px 20px; border:var(--border-w) solid #000;
  border-radius:2px; font-size:13.5px; font-weight:700; z-index:200;
  box-shadow:4px 4px 0 var(--primary); opacity:0; transition:all .15s ease;
  max-width:90vw; text-align:center}
#toast.show{opacity:1; transform:translateX(-50%) translateY(0)}

footer{max-width:1080px; margin:0 auto; padding:10px 16px 30px; display:flex; gap:10px; justify-content:center; flex-wrap:wrap}
.footer-note{text-align:center; font-size:12px; color:var(--muted-fg); padding:14px 16px 0}

.empty{padding:44px 20px; text-align:center; color:var(--muted-fg)}
.empty svg{width:52px; height:52px; color:#000; margin-bottom:10px; opacity:.3}
.empty p{font-size:14px}

@media(prefers-reduced-motion:reduce){*{animation:none!important; transition:none!important; scroll-behavior:auto}}

/* ---------- Example images gallery ---------- */
.ex-img-grid{display:grid; grid-template-columns:repeat(auto-fill, minmax(140px, 1fr)); gap:12px; margin-top:8px}
.ex-img-item{border:var(--border-w) solid #000; border-radius:2px; overflow:hidden; cursor:pointer;
  box-shadow:var(--shadow-sm); transition:transform .08s, box-shadow .08s; position:relative}
.ex-img-item:hover{transform:translate(-2px,-2px); box-shadow:var(--shadow-hover)}
.ex-img-item:active{transform:translate(1px,1px); box-shadow:var(--shadow-active)}
.ex-img-item img{width:100%; height:120px; object-fit:cover; display:block; border-bottom:2px solid #000}
.ex-img-name{display:block; padding:6px 8px; font-size:11px; font-weight:700; color:#000;
  white-space:nowrap; overflow:hidden; text-overflow:ellipsis; background:var(--yellow)}

/* ---------- Status Badge & PIN ---------- */
.status-badge{display:inline-flex; align-items:center; gap:4px; padding:6px 12px; border:var(--border-w) solid #000;
  border-radius:2px; font-size:12px; font-weight:700; cursor:pointer; box-shadow:2px 2px 0 #000;
  background:#fff; transition:transform .08s, box-shadow .08s; user-select:none}
.status-badge:hover{transform:translate(-1px,-1px); box-shadow:3px 3px 0 #000}
.status-badge.cloud{background:#DCFCE7; color:#166534}
.status-badge.local{background:#FEF3C7; color:#92400E}

.pin-display{font-size:24px; letter-spacing:12px; text-align:center; font-weight:bold}