/* =====================================================================
   UI v3 — clean professional theme
   One calm navy accent, neutral greys, flat surfaces with soft shadows.
   Class names are unchanged from earlier versions (btn-3d, card-3d, stat …) so every page picks this up.
   ===================================================================== */
:root {
  --ink: #0f172a; --muted: #64748b; --line: #e5e9f0; --line-strong: #d5dbe5;
  --bg: #f4f6f9; --surface: #ffffff; --surface-2: #f8fafc;
  --primary: #1f3b64; --primary-dark: #172c4b; --primary-soft: #e9eef6; --accent: #b08d57;
  --success: #2f7d4f; --success-soft: #e8f3ec; --danger: #b42318; --danger-soft: #fbeae8;
  --warning: #a15c07; --warning-soft: #fdf3e2; --info: #1f3b64;
  --sidebar: #13233c; --sidebar-2: #0f1d33; --sidebar-ink: #b7c2d3;
  --radius: 12px; --sw: 264px;
  --shadow-1: 0 1px 2px rgba(15,23,42,.05), 0 1px 1px rgba(15,23,42,.03);
  --shadow-2: 0 10px 30px -12px rgba(15,23,42,.22);
  --font: "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
}
[data-theme="dark"] {
  --ink: #e5e9f0; --muted: #94a3b8; --line: #243044; --line-strong: #2f3d55;
  --bg: #0b1220; --surface: #111a2b; --surface-2: #0e1626; --primary: #8fb0e0; --primary-dark: #a9c3ea; --primary-soft: #1a2940;
  --success-soft: #12291d; --danger-soft: #2d1414; --warning-soft: #2b2010;
  --shadow-1: 0 1px 2px rgba(0,0,0,.4); --shadow-2: 0 10px 30px -12px rgba(0,0,0,.7);
}
[data-theme="dark"] .table { --bs-table-color: var(--ink); --bs-table-bg: transparent; --bs-table-striped-color: var(--ink); --bs-table-hover-color: var(--ink); --bs-table-striped-bg: rgba(255,255,255,.03); --bs-table-hover-bg: rgba(255,255,255,.04); }
[data-theme="dark"] .form-control, [data-theme="dark"] .form-select { background-color: var(--surface-2); color: var(--ink); border-color: var(--line-strong); }
[data-theme="dark"] .dropdown-menu, [data-theme="dark"] .modal-content { background: var(--surface); color: var(--ink); }
[data-theme="dark"] .dropdown-item { color: var(--ink); }
[data-theme="dark"] .text-muted { color: var(--muted) !important; }
[data-theme="dark"] .list-group-item { background: var(--surface); color: var(--ink); border-color: var(--line); }
[data-theme="dark"] .bg-light, [data-theme="dark"] .table-light { background-color: var(--surface-2) !important; --bs-table-bg: var(--surface-2); color: var(--ink); }
[data-theme="dark"] .input-group-text { background: var(--surface-2); color: var(--ink); border-color: var(--line-strong); }

html, body { font-family: var(--font); color: var(--ink); }
body { min-height: 100vh; font-size: .925rem; background: var(--bg); }
a { color: var(--primary); text-decoration: none; font-weight: 600; }
a:hover { color: var(--primary-dark); text-decoration: underline; text-underline-offset: 2px; }
.text-muted { color: var(--muted) !important; }
::selection { background: rgba(31,59,100,.15); }

/* ---------------- Sidebar ---------------- */
.sidebar { position: fixed; inset: 0 auto 0 0; width: var(--sw); z-index: 1040; overflow-y: auto; scrollbar-width: thin;
  background: var(--sidebar); color: var(--sidebar-ink); padding: 18px 12px 28px; transition: transform .25s ease; border-right: 1px solid rgba(255,255,255,.04); }
.brand { display: flex; align-items: center; gap: 12px; color: #fff; padding: 4px 8px 16px; font-weight: 700; }
.brand:hover { color: #fff; text-decoration: none; }
.brand img { width: 40px; height: 40px; object-fit: contain; border-radius: 8px; background: #fff; padding: 3px; }
.brand-mark { width: 40px; height: 40px; border-radius: 10px; display: grid; place-items: center; font-size: 1.2rem; color: #fff; flex-shrink: 0; background: var(--primary); }
.brand-text { line-height: 1.2; font-size: .95rem; }
.role-pill { font-size: .66rem; text-transform: uppercase; letter-spacing: .12em; margin: 0 8px 12px; padding: 4px 10px; border-radius: 6px; display: inline-flex; gap: 6px; align-items: center;
  background: rgba(255,255,255,.06); color: #cfd8e6; font-weight: 700; }
.nav-section { font-size: .64rem; text-transform: uppercase; letter-spacing: .14em; color: rgba(183,194,211,.55); font-weight: 700; margin: 18px 12px 6px; }
.side-nav a { display: flex; align-items: center; gap: 11px; padding: 8px 10px; margin: 1px 0; border-radius: 8px; position: relative;
  color: var(--sidebar-ink); font-weight: 500; font-size: .88rem; transition: background .15s, color .15s; }
.side-nav a .chip { width: 22px; height: 22px; display: grid; place-items: center; font-size: 1rem; flex-shrink: 0; background: none !important; color: inherit !important; box-shadow: none !important; }
.side-nav a:hover { background: rgba(255,255,255,.05); color: #fff; text-decoration: none; }
.side-nav a.active { color: #fff; background: rgba(255,255,255,.09); font-weight: 600; }
.side-nav a.active::before { content: ""; position: absolute; left: -12px; top: 8px; bottom: 8px; width: 3px; border-radius: 0 3px 3px 0; background: var(--accent); }
.sidebar-foot { margin: 22px 8px 0; padding: 12px; border-radius: 8px; background: rgba(255,255,255,.04); font-size: .78rem; }
.sidebar-foot b { color: #fff; }

/* ---------------- Topbar ---------------- */
.topbar { position: sticky; top: 0; z-index: 1030; margin-left: var(--sw); display: flex; align-items: center; gap: 12px;
  padding: 12px 28px; background: var(--surface); border-bottom: 1px solid var(--line); }
.page-title { font-size: 1.15rem; font-weight: 700; margin: 0; }
.crumb { font-size: .76rem; color: var(--muted); font-weight: 500; }
.content { margin-left: var(--sw); padding: 26px 28px 60px; max-width: 1640px; }
.btn-icon { border: 1px solid var(--line-strong); background: var(--surface); color: var(--ink); border-radius: 8px; width: 38px; height: 38px; }
.btn-icon:hover { background: var(--surface-2); }
.btn-user { background: var(--surface); color: var(--ink); border-radius: 8px; border: 1px solid var(--line-strong); display: flex; align-items: center; gap: 10px; font-weight: 600; padding: 4px 10px 4px 5px; }
.btn-user:hover, .btn-user:focus { background: var(--surface-2); color: var(--ink); }
.avatar { width: 28px; height: 28px; border-radius: 6px; display: inline-grid; place-items: center; color: #fff; font-weight: 700; background: var(--primary); }
.dropdown-menu { border: 1px solid var(--line); border-radius: 10px; padding: 6px; box-shadow: var(--shadow-2) !important; }
.dropdown-item { border-radius: 6px; font-weight: 500; padding: 7px 12px; }
.sidebar-backdrop { display: none; }
@media (max-width: 991.98px) {
  .sidebar { transform: translateX(-100%); }
  body.sidebar-open .sidebar { transform: none; }
  body.sidebar-open .sidebar-backdrop { display: block; position: fixed; inset: 0; background: rgba(15,23,42,.45); z-index: 1035; }
  .topbar, .content { margin-left: 0; }
  .content { padding: 18px 16px 50px; }
  .topbar { padding: 10px 16px; }
}

/* ---------------- Buttons (flat, one accent) ---------------- */
.btn-3d { --b: var(--primary); --bh: var(--primary-dark); --fg: #fff;
  display: inline-flex; align-items: center; justify-content: center; gap: .45rem; border: 1px solid var(--b); border-radius: 8px;
  font-weight: 600; padding: .55rem 1.05rem; color: var(--fg); background: var(--b); box-shadow: 0 1px 2px rgba(15,23,42,.08); transition: background .15s, border-color .15s, box-shadow .15s; }
.btn-3d:hover { color: var(--fg); background: var(--bh); border-color: var(--bh); text-decoration: none; }
.btn-3d:active, .btn-3d.active { box-shadow: inset 0 2px 3px rgba(0,0,0,.15); }
.btn-3d:focus-visible { outline: 3px solid color-mix(in srgb, var(--b) 30%, transparent); outline-offset: 2px; }
.btn-3d:disabled { opacity: .55; }
.btn-3d.btn-sm { padding: .3rem .65rem; border-radius: 6px; font-size: .8rem; gap: .3rem; }
.btn-3d.btn-lg { padding: .75rem 1.5rem; font-size: 1rem; border-radius: 10px; }
.btn-3d.btn-primary, .btn-3d.btn-info, .btn-3d.btn-purple, .btn-3d.btn-dark { --b: var(--primary); --bh: var(--primary-dark); }
.btn-3d.btn-success { --b: var(--success); --bh: #25643f; }
.btn-3d.btn-danger  { --b: var(--danger); --bh: #912018; }
.btn-3d.btn-warning { --b: #fff; --bh: var(--warning-soft); --fg: var(--warning); border-color: #e7c89a; }
.btn-3d.btn-light   { --b: var(--surface); --bh: var(--surface-2); --fg: var(--ink); border-color: var(--line-strong); }
.btn-3d.btn-light:hover { color: var(--ink); }
[data-theme="dark"] .btn-3d.btn-primary, [data-theme="dark"] .btn-3d.btn-info, [data-theme="dark"] .btn-3d.btn-purple, [data-theme="dark"] .btn-3d.btn-dark { --b: #2c4d7e; --bh: #35598f; }
.btn-primary { --bs-btn-bg: var(--primary); --bs-btn-border-color: var(--primary); --bs-btn-hover-bg: var(--primary-dark); --bs-btn-hover-border-color: var(--primary-dark); --bs-btn-active-bg: var(--primary-dark); }
.btn-outline-primary { --bs-btn-color: var(--primary); --bs-btn-border-color: var(--primary); --bs-btn-hover-bg: var(--primary); --bs-btn-hover-border-color: var(--primary); }

/* ---------------- Cards & tiles ---------------- */
.card { background: var(--surface); color: var(--ink); border: 1px solid var(--line); border-radius: var(--radius); }
.card-3d { box-shadow: var(--shadow-1); }
.card-header { background: transparent; border-bottom: 1px solid var(--line); font-weight: 700; padding: 14px 20px; font-size: .93rem; display: flex; align-items: center; }
.card-header > i:first-child, .card-header > span > i:first-child { color: var(--primary); margin-right: 10px !important; font-size: 1rem; }
.card-header.text-danger > i:first-child { color: var(--danger); }
.card-header.text-success > i:first-child { color: var(--success); }
.card-body { padding: 20px; }

.stat { position: relative; padding: 18px; border-radius: var(--radius); height: 100%; display: block; color: var(--ink);
  background: var(--surface); border: 1px solid var(--line); box-shadow: var(--shadow-1); transition: border-color .15s, box-shadow .15s; }
.stat:hover { color: var(--ink); border-color: var(--line-strong); box-shadow: var(--shadow-2); text-decoration: none; }
.stat .ico { width: 40px; height: 40px; border-radius: 10px; display: grid; place-items: center; font-size: 1.15rem; color: var(--primary); background: var(--primary-soft); }
.stat .num { font-size: 1.6rem; font-weight: 700; line-height: 1.1; margin-top: 12px; font-variant-numeric: tabular-nums; }
.stat .lbl { color: var(--muted); font-size: .72rem; font-weight: 600; text-transform: uppercase; letter-spacing: .08em; margin-top: 2px; }

/* Welcome banner */
.hero { position: relative; overflow: hidden; border-radius: var(--radius); padding: 24px 28px; color: #fff; margin-bottom: 24px; background: var(--primary);
  border-left: 4px solid var(--accent); }
.hero h2 { font-weight: 700; margin: 0; font-size: clamp(1.3rem, 2.4vw, 1.8rem); }
.hero p { margin: 4px 0 0; color: rgba(255,255,255,.8); }
.hero .cube { display: none; }
.hero .btn-3d.btn-light { --b: #fff; --bh: #eef2f7; --fg: var(--primary); border-color: #fff; }

.table { color: var(--ink); margin-bottom: 0; }
.table > :not(caption) > * > * { padding: .68rem .8rem; border-color: var(--line); }
.table thead th { font-size: .7rem; text-transform: uppercase; letter-spacing: .07em; color: var(--muted); font-weight: 700; background: var(--surface-2); white-space: nowrap; border-bottom: 1px solid var(--line-strong); }
.table-hover > tbody > tr:hover > * { background: var(--surface-2); }
.form-control, .form-select { border-radius: 8px; border: 1px solid var(--line-strong); padding: .52rem .8rem; background-color: var(--surface); transition: border-color .15s, box-shadow .15s; }
.form-control:focus, .form-select:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(31,59,100,.12); }
.form-control-sm, .form-select-sm { border-radius: 6px; padding: .28rem .5rem; }
.form-label { font-weight: 600; font-size: .8rem; margin-bottom: .35rem; color: #334155; }
[data-theme="dark"] .form-label { color: var(--ink); }
.form-check-input { width: 1.1em; height: 1.1em; border: 1.5px solid var(--line-strong); }
.form-check-input:checked { background-color: var(--primary); border-color: var(--primary); }
.input-group-text { border-radius: 8px; background: var(--surface-2); border-color: var(--line-strong); color: var(--muted); }
.alert-3d { border: 1px solid var(--line); border-radius: 10px; border-left: 4px solid currentColor; box-shadow: var(--shadow-1); }
.badge { font-weight: 600; letter-spacing: .02em; padding: .4em .65em; border-radius: 6px; }
.badge-soft { background: var(--primary-soft); color: var(--primary); }
.text-bg-success { background: var(--success-soft) !important; color: var(--success) !important; }
.text-bg-danger { background: var(--danger-soft) !important; color: var(--danger) !important; }
.text-bg-warning { background: var(--warning-soft) !important; color: var(--warning) !important; }
.text-bg-info, .text-bg-primary { background: var(--primary-soft) !important; color: var(--primary) !important; }
.text-bg-secondary { background: #eef1f5 !important; color: #475569 !important; }
.empty { text-align: center; color: var(--muted); padding: 36px 10px; }
.empty i { font-size: 2.2rem; display: block; margin-bottom: 8px; opacity: .45; }
.photo-thumb { width: 40px; height: 40px; border-radius: 8px; object-fit: cover; background: var(--surface-2); border: 1px solid var(--line); }
.photo-lg { width: 120px; height: 140px; object-fit: cover; border-radius: 10px; border: 1px solid var(--line-strong); background: var(--surface-2); }
.nav-tabs { border-bottom: 1px solid var(--line); gap: 4px; }
.nav-tabs .nav-link { font-weight: 600; color: var(--muted); border: 0; border-bottom: 2px solid transparent; border-radius: 0; padding: .6rem .9rem; background: none; }
.nav-tabs .nav-link:hover { color: var(--ink); }
.nav-tabs .nav-link.active { color: var(--primary); background: none; border-bottom-color: var(--primary); }
.material-item { display: flex; gap: 14px; align-items: flex-start; padding: 14px; border: 1px solid var(--line); border-radius: 10px; background: var(--surface); margin-bottom: 10px; }
.material-item:hover { border-color: var(--line-strong); }
.material-item .mi-ico { width: 40px; height: 40px; border-radius: 8px; display: grid; place-items: center; font-size: 1.15rem; color: var(--primary); background: var(--primary-soft); flex-shrink: 0; }
.progress { height: 8px; border-radius: 99px; background: #e9edf3; }
.progress-bar { border-radius: 99px; background: var(--primary); }
.marks-grid input { width: 74px; text-align: center; padding: .3rem; font-weight: 600; }
.sticky-actions { position: sticky; bottom: 0; background: var(--surface); padding: 14px 16px; border-top: 1px solid var(--line); z-index: 5; border-radius: 0 0 var(--radius) var(--radius); }
.ai-card { background: var(--surface); border-left: 4px solid var(--accent); }
.search-bar { max-width: 340px; }
.list-group-item { border-color: var(--line); }
.pagination .page-link { border-radius: 6px !important; margin: 0 2px; border-color: var(--line); color: var(--primary); font-weight: 600; }
.pagination .active .page-link { background: var(--primary); border-color: var(--primary); color: #fff; }

/* Section heading */
.section-head { display: flex; align-items: center; gap: 14px; margin-bottom: 18px; }
.section-head .ico { width: 44px; height: 44px; border-radius: 10px; display: grid; place-items: center; font-size: 1.25rem; color: var(--primary); background: var(--primary-soft); flex-shrink: 0; }
.section-head h3 { margin: 0; font-weight: 700; font-size: 1.15rem; }
.section-head p { margin: 0; color: var(--muted); font-size: .86rem; }

/* Option tiles (radio cards) */
.opt-tiles { display: grid; grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); gap: 10px; }
.opt-tiles input { position: absolute; opacity: 0; pointer-events: none; }
.opt-tiles label { display: block; cursor: pointer; border-radius: 10px; padding: 10px; text-align: center; font-weight: 600; font-size: .8rem; background: var(--surface);
  border: 1.5px solid var(--line-strong); transition: border-color .12s, background .12s; }
.opt-tiles label:hover { border-color: #b7c2d3; }
.opt-tiles label i { color: var(--muted); }
.opt-tiles label .sw { display: block; height: 42px; border-radius: 6px; margin-bottom: 6px; }
.opt-tiles input:checked + label { border-color: var(--primary); color: var(--primary); background: var(--primary-soft); }
.opt-tiles input:checked + label i { color: var(--primary); }
.opt-tiles input:focus-visible + label { outline: 3px solid rgba(31,59,100,.25); }

/* Student Desk */
.desk-steps { display: flex; gap: 10px; flex-wrap: wrap; }
.desk-step { flex: 1; min-width: 200px; display: flex; align-items: center; gap: 10px; padding: 12px 16px; border-radius: 10px; background: var(--surface); border: 1px solid var(--line); color: var(--ink); font-weight: 600; }
.desk-step:hover { border-color: var(--primary); text-decoration: none; }
.desk-step span { width: 26px; height: 26px; border-radius: 50%; display: grid; place-items: center; background: var(--primary); color: #fff; font-size: .8rem; }
.desk-marks .form-control { text-align: right; }
.date-pill { padding: 6px 12px; border-radius: 8px; background: var(--surface-2); border: 1px solid var(--line); font-size: .82rem; }
.doc-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(210px, 1fr)); gap: 12px; }
.doc-tile { border: 1px solid var(--line); border-radius: 10px; padding: 14px; background: var(--surface); display: flex; flex-direction: column; }
.doc-tile:hover { border-color: var(--line-strong); box-shadow: var(--shadow-1); }
.doc-ico { width: 36px; height: 36px; border-radius: 8px; display: grid; place-items: center; background: var(--primary-soft); color: var(--primary); font-size: 1.05rem; margin-bottom: 8px; }
.doc-name { font-weight: 600; line-height: 1.25; }
.doc-prev { font-size: .76rem; margin-top: 4px; margin-bottom: auto; }

/* ---------------- Login ---------------- */
.auth-wrap { min-height: 100vh; display: grid; grid-template-columns: 1.1fr 1fr; background: var(--bg); }
.auth-hero { position: relative; overflow: hidden; color: #fff; padding: 64px; display: flex; flex-direction: column; justify-content: center; background: var(--sidebar); }
.auth-hero::after { content: ""; position: absolute; left: 64px; bottom: 56px; width: 64px; height: 3px; background: var(--accent); }
.auth-hero h1 { font-weight: 700; font-size: clamp(1.9rem, 3vw, 2.6rem); line-height: 1.15; max-width: 16ch; }
.auth-hero .lead { color: #b7c2d3; max-width: 42ch; }
.auth-feature { display: flex; gap: 12px; align-items: center; margin-top: 12px; color: #d5dde8; font-weight: 500; }
.auth-feature i { width: 36px; height: 36px; border-radius: 8px; display: grid; place-items: center; font-size: 1.05rem; background: rgba(255,255,255,.07); color: #e6d3b3; }
.float-card { display: none !important; }
.auth-form { display: flex; align-items: center; justify-content: center; padding: 32px; }
.auth-card { width: 100%; max-width: 420px; background: var(--surface); border-radius: 14px; padding: 32px 30px; border: 1px solid var(--line); box-shadow: var(--shadow-2); }
.role-tabs { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; }
.role-tabs input { display: none; }
.role-tabs label { text-align: center; padding: 10px 4px; border-radius: 8px; background: var(--surface); border: 1.5px solid var(--line-strong); cursor: pointer; font-weight: 600; font-size: .74rem; color: var(--muted); }
.role-tabs label i { display: block; font-size: 1.2rem; margin-bottom: 2px; }
.role-tabs input:checked + label { border-color: var(--primary); color: var(--primary); background: var(--primary-soft); }
@media (max-width: 900px) { .auth-wrap { grid-template-columns: 1fr; } .auth-hero { display: none; } }

/* ---------------- Print ---------------- */
@media print {
  .sidebar, .topbar, .no-print, .alert { display: none !important; }
  .content { margin: 0 !important; padding: 0 !important; }
  body { background: #fff !important; }
}
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { transition: none !important; } }
.btn-group > .btn { font-weight: 600; }
.hero .btn-3d.btn-dark, .hero .btn-3d.btn-primary, .hero .btn-3d.btn-info, .hero .btn-3d.btn-purple { --b: transparent; --bh: rgba(255,255,255,.1); border-color: rgba(255,255,255,.55); --fg: #fff; }
.hero .btn-3d.btn-warning { --b: #fff; --bh: #fff7ea; }