/* KXD-EduData – web giảng viên. Màu theo phần mềm: xanh DUT #075289, vàng #FCDF05 */
:root {
  --navy: #075289; --navy-dark: #0a3d66; --blue: #106fb1; --yellow: #fcdf05;
  --bg: #f3f6fa; --card: #ffffff; --line: #d6dee8; --text: #1d2733; --muted: #5a6473;
  --ok: #1e7b45; --warn: #9c5700; --bad: #b3261e; --radius: 8px;
  font-size: 15px;
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; }
body { font-family: Tahoma, "Segoe UI", Roboto, Arial, sans-serif; color: var(--text); background: var(--bg); line-height: 1.45; }
[hidden] { display: none !important; }
h1, h2, h3 { margin: 0 0 .4em; line-height: 1.25; }
.muted { color: var(--muted); }
.noscript { padding: 2rem; text-align: center; }
a { color: var(--blue); }

/* ---------- nút, ô nhập ---------- */
.btn { display: inline-block; text-decoration: none; font: inherit; font-weight: bold; border: 1px solid transparent; border-radius: 6px; padding: .5em 1em; cursor: pointer; background: #e9eff6; color: var(--navy); }
.btn:hover { filter: brightness(.96); }
.btn:disabled { opacity: .55; cursor: default; }
.btn.primary { background: var(--navy); color: var(--yellow); }
.btn.ok { background: var(--ok); color: #fff; }
.btn.danger { background: #fff; color: var(--bad); border-color: #e5b9b6; }
.btn.ghost { background: transparent; color: #fff; border-color: rgba(255,255,255,.45); }
.btn.link { background: none; color: var(--muted); font-weight: normal; }
.btn.small { padding: .3em .7em; font-size: .9em; }
.btn.wide { width: 100%; margin-top: .8em; }
.icon-btn { font: inherit; background: none; border: 0; cursor: pointer; font-size: 1.2em; padding: .2em .5em; color: inherit; }
input, select, textarea { font: inherit; width: 100%; padding: .55em .7em; border: 1px solid var(--line); border-radius: 6px; background: #fff; color: var(--text); }
input:focus, select:focus, textarea:focus, .btn:focus-visible, a:focus-visible { outline: 2px solid var(--blue); outline-offset: 1px; }
textarea { min-height: 7em; resize: vertical; }
label { display: block; font-weight: bold; font-size: .9em; color: var(--navy); margin: .8em 0 .3em; }
label.check { display: flex; gap: .5em; align-items: center; font-weight: normal; color: var(--text); }
label.check input { width: auto; }
.msg { min-height: 1.2em; color: var(--bad); margin: .7em 0 0; }
.msg.ok { color: var(--ok); }

/* ---------- đăng nhập ---------- */
.login { min-height: 100%; display: flex; align-items: center; justify-content: center; gap: 3rem; padding: 2rem 1rem;
         background: linear-gradient(135deg, var(--navy-dark), var(--navy) 60%, #0c64a3); }
.login-brand { color: #fff; max-width: 360px; }
.login-brand h1 { font-family: "Arial Black", Arial, sans-serif; color: var(--yellow); font-size: 2.2rem; letter-spacing: .02em; margin-top: .4em; }
.brand-sub { font-size: 1.15rem; font-weight: bold; margin: 0; }
.brand-unit { color: #cfe0f1; white-space: pre-line; }
.brand-mark { display: inline-flex; align-items: center; justify-content: center; width: 64px; height: 64px; border-radius: 12px;
              background: var(--yellow); color: var(--navy-dark); font-family: "Arial Black", Arial, sans-serif; font-size: 1.1rem; }
.brand-mark.small { width: 30px; height: 30px; border-radius: 6px; font-size: .62rem; margin-right: .5em; }
.login-card { background: #fff; width: 100%; max-width: 400px; padding: 1.8rem; border-radius: 12px; box-shadow: 0 10px 30px rgba(0,0,0,.25); }
.login-card h2 { color: var(--navy); }
.login-card .note { font-size: .82em; color: var(--muted); border-top: 1px solid var(--line); padding-top: .8em; margin-top: 1em; }

/* ---------- khung ứng dụng ---------- */
.app { display: grid; grid-template-columns: 250px 1fr; grid-template-rows: 56px 1fr; min-height: 100%; }
.topbar { grid-column: 1 / 3; display: flex; align-items: center; gap: 1rem; padding: 0 1rem; background: var(--navy); color: #fff; border-bottom: 4px solid var(--yellow); }
.topbar-brand { display: flex; align-items: center; font-weight: bold; color: var(--yellow); font-size: 1.05rem; }
.topbar-brand .muted { color: #cfe0f1; margin-left: .4em; font-weight: normal; }
.topbar-user { margin-left: auto; text-align: right; line-height: 1.2; }
.user-name { font-weight: bold; }
.user-role { font-size: .82em; color: var(--yellow); }
.menu-btn { display: none; color: #fff; }
.sidenav { background: var(--navy-dark); color: #fff; padding: .8rem 0; overflow-y: auto; }
.sidenav a { display: flex; align-items: center; gap: .5em; padding: .6em 1.1em; color: #fff; text-decoration: none; border-left: 4px solid transparent; }
.sidenav a:hover { background: #12558c; }
.sidenav a.active { background: var(--blue); border-left-color: var(--yellow); font-weight: bold; }
.sidenav a.nav-accent { color: var(--yellow); font-weight: bold; }
.nav-sep { font-size: .75em; font-weight: bold; color: #8fb8de; padding: 1.1em 1.1em .3em; letter-spacing: .04em; }
.nav-tables a { padding-left: 1.8em; font-size: .92em; }
.nav-tables .nav-sep { padding-left: 1.8em; padding-top: .7em; }
.badge { background: var(--yellow); color: var(--navy-dark); border-radius: 10px; padding: 0 .5em; font-size: .8em; font-weight: bold; margin-left: auto; }
.content { padding: 1.4rem 1.6rem 3rem; overflow-x: hidden; min-width: 0; }
.content:focus { outline: none; }

/* ---------- trang ---------- */
.page-head { display: flex; align-items: flex-start; gap: 1rem; flex-wrap: wrap; margin-bottom: 1rem; }
.page-head h2 { color: var(--navy); font-size: 1.35rem; }
.page-head .actions { margin-left: auto; display: flex; gap: .5rem; flex-wrap: wrap; }
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem 1.2rem; margin-bottom: 1rem; }
.card h3 { color: var(--navy); font-size: 1.05rem; }
.grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 1rem; }
.stat { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: .9rem 1rem; }
.stat .v { font-size: 1.6rem; font-weight: bold; color: var(--navy); }
.stat .l { color: var(--muted); font-size: .88em; }
.tile { display: block; text-decoration: none; color: inherit; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); padding: .9rem 1rem; }
.tile:hover { border-color: var(--blue); box-shadow: 0 2px 8px rgba(16,111,177,.12); }
.tile .t { font-weight: bold; color: var(--navy); }
.tile .d { font-size: .85em; color: var(--muted); }
.tile .n { float: right; font-weight: bold; color: var(--blue); }
.group-title { color: var(--navy); font-size: 1rem; border-bottom: 1px solid var(--line); padding-bottom: .3em; margin: 1.4rem 0 .8rem; }
.kv { display: grid; grid-template-columns: minmax(140px, 38%) 1fr; gap: .1rem 1rem; }
.kv dt { color: var(--muted); font-size: .9em; padding: .35em 0; border-bottom: 1px solid #eef2f6; }
.kv dd { margin: 0; padding: .35em 0; border-bottom: 1px solid #eef2f6; word-break: break-word; white-space: pre-wrap; }
.mt { margin-top: .8rem; }
.mb { margin: .6rem 0 1rem; }
.table-wrap.short { max-height: 420px; }
.card.narrow { max-width: 720px; }
.hint { font-size: .86em; color: var(--muted); }
.info { background: #eef5fc; border: 1px solid #cfe0f1; border-radius: var(--radius); padding: .7rem 1rem; color: #24425f; font-size: .92em; }

/* ---------- bảng dữ liệu ---------- */
.toolbar { display: flex; gap: .6rem; flex-wrap: wrap; align-items: center; margin-bottom: .8rem; }
.toolbar input[type=search] { max-width: 300px; }
.toolbar select { width: auto; }
.toolbar label.check { margin: 0; }
.table-wrap { overflow: auto; background: #fff; border: 1px solid var(--line); border-radius: var(--radius); max-height: calc(100vh - 260px); }
table.data { border-collapse: collapse; width: 100%; font-size: .9em; }
table.data th { position: sticky; top: 0; background: #0487d9; color: #fff; text-align: left; padding: .55em .7em; white-space: nowrap; font-weight: bold; z-index: 1; }
table.data td { padding: .45em .7em; border-bottom: 1px solid #eef2f6; vertical-align: top; max-width: 380px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
table.data tbody tr { cursor: pointer; }
table.data tbody tr:hover { background: #eaf3fc; }
table.data td.num { text-align: right; white-space: nowrap; }
table.data tr.mine td:first-child { box-shadow: inset 4px 0 0 var(--yellow); }
.pager { display: flex; gap: .6rem; align-items: center; margin-top: .7rem; flex-wrap: wrap; }
.empty { padding: 2rem; text-align: center; color: var(--muted); }

/* ---------- phản hồi ---------- */
.fb { border-left: 4px solid var(--line); }
.fb.s-moi { border-left-color: var(--blue); }
.fb.s-dang { border-left-color: #e89a00; }
.fb.s-xong { border-left-color: var(--ok); }
.fb.s-khong { border-left-color: var(--bad); }
.fb-head { display: flex; gap: .6rem; flex-wrap: wrap; align-items: center; }
.pill { display: inline-block; border-radius: 12px; padding: .05em .7em; font-size: .82em; font-weight: bold; background: #e9eff6; color: var(--navy); }
.pill.s-moi { background: #dcebf8; color: #0b4f86; }
.pill.s-dang { background: #fff1d6; color: var(--warn); }
.pill.s-xong { background: #dff3e6; color: var(--ok); }
.pill.s-khong { background: #f9e1df; color: var(--bad); }
.pill.s-rut { background: #eceff3; color: #6b7480; }
.reply { background: #f3f8f4; border: 1px solid #cfe6d6; border-radius: 6px; padding: .6rem .8rem; margin-top: .6rem; white-space: pre-wrap; }
.reply b { color: var(--ok); }
.quote { white-space: pre-wrap; margin: .5rem 0 0; }
.ref { font-size: .86em; color: var(--muted); }

/* ---------- ngăn chi tiết, thông báo ---------- */
.overlay { position: fixed; inset: 0; background: rgba(10, 30, 50, .35); z-index: 20; }
.drawer { position: fixed; top: 0; right: 0; bottom: 0; width: min(560px, 100%); background: #fff; z-index: 21; display: flex; flex-direction: column; box-shadow: -6px 0 24px rgba(0,0,0,.2); }
.drawer-head { display: flex; align-items: center; gap: .5rem; padding: .9rem 1.2rem; border-bottom: 1px solid var(--line); }
.drawer-head h3 { color: var(--navy); margin: 0; font-size: 1.1rem; }
.drawer-head .icon-btn { margin-left: auto; }
.drawer-body { padding: 1rem 1.2rem 2rem; overflow-y: auto; }
.toast { position: fixed; bottom: 1.2rem; left: 50%; transform: translateX(-50%); background: #1d2733; color: #fff; padding: .7em 1.2em; border-radius: 8px; z-index: 30; max-width: 90%; }
.toast.ok { background: var(--ok); }
.toast.bad { background: var(--bad); }
.loading { padding: 1.5rem; color: var(--muted); }

/* ---------- điện thoại ---------- */
@media (max-width: 860px) {
  .app { grid-template-columns: 1fr; }
  .topbar { grid-column: 1; }
  .menu-btn { display: inline-block; }
  .hide-sm, .topbar-user { display: none; }
  .topbar { gap: .5rem; padding: 0 .6rem; }
  .topbar-brand { white-space: nowrap; }
  .topbar .btn.ghost { margin-left: auto; padding: .35em .7em; }
  .sidenav { position: fixed; top: 60px; left: 0; bottom: 0; width: 260px; z-index: 15; transform: translateX(-100%); transition: transform .2s; }
  .sidenav.open { transform: none; }
  .content { padding: 1rem; }
  .login { flex-direction: column; gap: 1.2rem; }
  .login-brand { text-align: center; }
  .kv { grid-template-columns: 1fr; }
  .kv dt { border-bottom: 0; padding-bottom: 0; }
}