:root {
  --green-900: #06331f;
  --green-800: #0a4a2e;
  --green-700: #0d5f3a;
  --green-600: #137a4b;
  --green-100: #e3f2ea;
  --green-50:  #f1f8f4;
  --amber: #e8a317;
  --amber-100: #fdf3dc;
  --red: #c0392b;
  --red-100: #fbe6e3;
  --blue: #1f6fb2;
  --blue-100: #e3eef8;
  --ink: #17221c;
  --ink-2: #4a5a51;
  --ink-3: #7b8a81;
  --line: #dfe6e1;
  --bg: #f5f7f4;
  --card: #ffffff;
  --radius: 10px;
  --shadow: 0 1px 2px rgba(10, 40, 25, .06), 0 4px 16px rgba(10, 40, 25, .06);
  --font: "Plus Jakarta Sans", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
* { box-sizing: border-box; }
html, body { margin: 0; }
body { font-family: var(--font); color: var(--ink); background: var(--bg); font-size: 15px; line-height: 1.5; -webkit-font-smoothing: antialiased; }
a { color: var(--green-700); }
h1, h2, h3, h4 { line-height: 1.25; margin: 0 0 .5em; }
h1 { font-size: 1.7rem; letter-spacing: -.01em; }
h2 { font-size: 1.3rem; }
h3 { font-size: 1.08rem; }
p { margin: 0 0 .8em; }
small, .muted { color: var(--ink-3); }
.hidden { display: none !important; }
.row { display: flex; gap: 12px; align-items: center; flex-wrap: wrap; }
.row.between { justify-content: space-between; }
.grow { flex: 1; }
.stack > * + * { margin-top: 12px; }
.grid { display: grid; gap: 14px; }
.grid.cols-2 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.grid.cols-3 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.grid.cols-4 { grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); }
.wrap { max-width: 1100px; margin: 0 auto; padding: 20px 16px 60px; }

/* ---------- Top bar ---------- */
.topbar { background: var(--green-800); color: #fff; }
.topbar .inner { max-width: 1100px; margin: 0 auto; padding: 12px 16px; display: flex; align-items: center; gap: 14px; }
.brand { display: flex; align-items: center; gap: 10px; color: #fff; text-decoration: none; font-weight: 700; }
.brand .logo { width: 34px; height: 34px; border-radius: 8px; background: var(--amber); color: var(--green-900); display: grid; place-items: center; font-weight: 800; font-size: 14px; }
.brand small { display: block; color: #b9d8c7; font-weight: 500; font-size: 12px; }
.topbar .spacer { flex: 1; }
.topbar .who { text-align: right; font-size: 13px; line-height: 1.3; }
.topbar .who small { color: #b9d8c7; }

/* ---------- Cards ---------- */
.card { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 18px; }
.card.flat { box-shadow: none; }
.card h3 { margin-bottom: 8px; }
.stat { padding: 16px; }
.stat .num { font-size: 1.8rem; font-weight: 800; color: var(--green-700); line-height: 1.1; }
.stat .lbl { color: var(--ink-2); font-size: 13px; }

/* ---------- Buttons / inputs ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 6px; border: 1px solid transparent; border-radius: 8px; padding: 9px 16px; font: inherit; font-weight: 600; cursor: pointer; text-decoration: none; background: var(--green-700); color: #fff; transition: background .15s, transform .05s; white-space: nowrap; }
.btn:hover { background: var(--green-600); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: .55; cursor: not-allowed; }
.btn.secondary { background: #fff; color: var(--green-800); border-color: var(--line); }
.btn.secondary:hover { background: var(--green-50); }
.btn.danger { background: var(--red); }
.btn.danger:hover { background: #a93226; }
.btn.amber { background: var(--amber); color: var(--green-900); }
.btn.ghost { background: transparent; color: var(--ink-2); }
.btn.ghost:hover { background: var(--green-50); }
.btn.sm { padding: 5px 10px; font-size: 13px; }
.btn.lg { padding: 13px 22px; font-size: 16px; }
.btn.block { width: 100%; }
label { display: block; font-weight: 600; font-size: 13px; color: var(--ink-2); margin-bottom: 4px; }
input[type=text], input[type=password], input[type=email], input[type=number], input[type=url], input[type=datetime-local], input[type=search], select, textarea {
  width: 100%; font: inherit; color: var(--ink); background: #fff; border: 1px solid #cdd6d0; border-radius: 8px; padding: 9px 11px; outline: none;
}
input:focus, select:focus, textarea:focus { border-color: var(--green-600); box-shadow: 0 0 0 3px rgba(19, 122, 75, .15); }
textarea { resize: vertical; min-height: 80px; }
.field { margin-bottom: 12px; }
.check { display: block; position: relative; padding-left: 26px; font-weight: 500; color: var(--ink); font-size: 14px; margin: 0; cursor: pointer; }
.check input { position: absolute; left: 0; top: 2px; width: 17px; height: 17px; margin: 0; accent-color: var(--green-700); }
.help { font-size: 12.5px; color: var(--ink-3); margin-top: 3px; }

/* ---------- Tables ---------- */
.table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: #fff; }
table { border-collapse: collapse; width: 100%; font-size: 14px; }
th, td { padding: 9px 12px; text-align: left; border-bottom: 1px solid var(--line); vertical-align: top; }
th { background: var(--green-50); font-size: 12px; text-transform: uppercase; letter-spacing: .04em; color: var(--ink-2); white-space: nowrap; position: sticky; top: 0; }
tr:last-child td { border-bottom: none; }
tbody tr:hover { background: #fafcfb; }
td.num, th.num { text-align: right; font-variant-numeric: tabular-nums; }

/* ---------- Pills ---------- */
.pill { display: inline-block; padding: 2px 9px; border-radius: 99px; font-size: 12px; font-weight: 600; background: var(--green-100); color: var(--green-800); white-space: nowrap; }
.pill.amber { background: var(--amber-100); color: #8a5d00; }
.pill.red { background: var(--red-100); color: var(--red); }
.pill.blue { background: var(--blue-100); color: var(--blue); }
.pill.grey { background: #eceeed; color: var(--ink-2); }

/* ---------- Tabs ---------- */
.tabs { display: flex; gap: 4px; border-bottom: 1px solid var(--line); margin-bottom: 18px; overflow-x: auto; }
.tabs button { background: none; border: none; font: inherit; font-weight: 600; color: var(--ink-2); padding: 10px 14px; cursor: pointer; border-bottom: 3px solid transparent; white-space: nowrap; }
.tabs button.active { color: var(--green-700); border-bottom-color: var(--green-700); }

/* ---------- Modal / toast ---------- */
.modal-back { position: fixed; inset: 0; background: rgba(6, 30, 18, .5); display: flex; align-items: flex-start; justify-content: center; padding: 40px 16px; z-index: 50; overflow-y: auto; }
.modal { background: #fff; border-radius: 12px; width: 100%; max-width: 640px; box-shadow: 0 20px 60px rgba(0,0,0,.25); }
.modal.wide { max-width: 980px; }
.modal header { padding: 16px 20px; border-bottom: 1px solid var(--line); display: flex; align-items: center; gap: 10px; }
.modal header h3 { margin: 0; flex: 1; }
.modal .body { padding: 18px 20px; }
.modal footer { padding: 14px 20px; border-top: 1px solid var(--line); display: flex; justify-content: flex-end; gap: 8px; flex-wrap: wrap; }
.toasts { position: fixed; bottom: 18px; left: 50%; transform: translateX(-50%); z-index: 99; display: flex; flex-direction: column; gap: 8px; align-items: center; width: calc(100% - 32px); max-width: 460px; }
.toast { background: var(--green-900); color: #fff; padding: 10px 16px; border-radius: 8px; box-shadow: var(--shadow); font-size: 14px; animation: pop .2s ease-out; }
.toast.error { background: var(--red); }
.toast.warn { background: var(--amber); color: var(--green-900); }
@keyframes pop { from { opacity: 0; transform: translateY(8px); } }

.banner { padding: 10px 14px; border-radius: 8px; font-size: 14px; margin-bottom: 14px; }
.banner.demo { background: var(--amber-100); color: #6d4a00; border: 1px solid #f1d58f; }
.banner.info { background: var(--blue-100); color: #174f80; }
.banner.error { background: var(--red-100); color: var(--red); }
.empty { text-align: center; color: var(--ink-3); padding: 36px 16px; }

/* ---------- Landing ---------- */
.hero { background: radial-gradient(1200px 400px at 80% -10%, #1d8a57 0%, transparent 60%), var(--green-800); color: #fff; }
.hero .inner { max-width: 1100px; margin: 0 auto; padding: 48px 16px 64px; display: grid; grid-template-columns: 1.2fr 1fr; gap: 40px; align-items: center; }
.hero h1 { font-size: 2.4rem; color: #fff; }
.hero p.lead { color: #cfe6d9; font-size: 1.08rem; max-width: 520px; }
.hero .feats { display: grid; grid-template-columns: 1fr 1fr; gap: 10px 18px; margin-top: 22px; color: #e3f2ea; font-size: 14px; }
.hero .feats div::before { content: "✓"; color: var(--amber); font-weight: 800; margin-right: 8px; }
.login-card { background: #fff; color: var(--ink); border-radius: 14px; padding: 26px; box-shadow: 0 20px 50px rgba(0,0,0,.25); }
@media (max-width: 820px) { .hero .inner { grid-template-columns: 1fr; padding: 30px 16px 40px; } .hero h1 { font-size: 1.8rem; } }

/* ---------- Exam room ---------- */
body.exam { background: #eef2ef; user-select: none; -webkit-user-select: none; }
.exam-top { background: var(--green-900); color: #fff; position: sticky; top: 0; z-index: 20; }
.exam-top .inner { max-width: 1200px; margin: 0 auto; padding: 10px 16px; display: flex; align-items: center; gap: 14px; flex-wrap: wrap; }
.timer { font-variant-numeric: tabular-nums; font-weight: 800; font-size: 1.35rem; background: rgba(255,255,255,.1); padding: 4px 14px; border-radius: 8px; letter-spacing: .03em; }
.timer.low { background: var(--red); animation: blink 1s steps(2) infinite; }
@keyframes blink { 50% { opacity: .75; } }
.save-state { font-size: 12px; color: #b9d8c7; }
.save-state.off { color: #ffcf6e; }
.subject-tabs { background: #fff; border-bottom: 1px solid var(--line); }
.subject-tabs .inner { max-width: 1200px; margin: 0 auto; padding: 0 16px; display: flex; gap: 2px; overflow-x: auto; }
.subject-tabs button { border: none; background: none; font: inherit; font-weight: 700; padding: 12px 16px; color: var(--ink-2); cursor: pointer; border-bottom: 3px solid transparent; white-space: nowrap; }
.subject-tabs button.active { color: var(--green-700); border-bottom-color: var(--amber); }
.subject-tabs button .cnt { font-weight: 500; font-size: 12px; color: var(--ink-3); margin-left: 4px; }
.exam-body { max-width: 1200px; margin: 0 auto; padding: 18px 16px 40px; display: grid; grid-template-columns: 1fr 320px; gap: 18px; }
@media (max-width: 900px) { .exam-body { grid-template-columns: 1fr; } }
.qcard { background: #fff; border-radius: 12px; border: 1px solid var(--line); padding: 22px; min-height: 360px; display: flex; flex-direction: column; }
.qnum { font-size: 13px; font-weight: 700; color: var(--green-700); text-transform: uppercase; letter-spacing: .05em; margin-bottom: 10px; }
.qtext { font-size: 1.12rem; line-height: 1.6; margin-bottom: 18px; }
.qtext img, .rich img { max-width: 100%; border-radius: 6px; }
.opts { display: flex; flex-direction: column; gap: 10px; }
.opt { display: flex; gap: 12px; align-items: flex-start; border: 2px solid var(--line); border-radius: 10px; padding: 12px 14px; cursor: pointer; transition: border-color .1s, background .1s; font-size: 1.02rem; }
.opt:hover { border-color: #a9c9b7; }
.opt .letter { flex: none; width: 30px; height: 30px; border-radius: 50%; border: 2px solid #b8c6bd; display: grid; place-items: center; font-weight: 800; font-size: 14px; color: var(--ink-2); }
.opt.selected { border-color: var(--green-600); background: var(--green-50); }
.opt.selected .letter { background: var(--green-700); border-color: var(--green-700); color: #fff; }
.opt .otext { padding-top: 3px; }
.qnav { margin-top: auto; padding-top: 20px; display: flex; gap: 10px; flex-wrap: wrap; }
.palette { background: #fff; border-radius: 12px; border: 1px solid var(--line); padding: 16px; align-self: start; position: sticky; top: 120px; }
.palette .grid-q { display: grid; grid-template-columns: repeat(auto-fill, minmax(38px, 1fr)); gap: 6px; max-height: 340px; overflow-y: auto; padding: 2px; }
.palette .grid-q button { border: 1px solid #ccd6cf; background: #f4f6f5; border-radius: 6px; height: 36px; font: inherit; font-size: 13px; font-weight: 700; color: var(--ink-2); cursor: pointer; }
.palette .grid-q button.done { background: var(--green-600); border-color: var(--green-600); color: #fff; }
.palette .grid-q button.flag { box-shadow: inset 0 -4px 0 var(--amber); }
.palette .grid-q button.current { outline: 3px solid var(--amber); outline-offset: 1px; }
.legend { display: flex; gap: 14px; flex-wrap: wrap; font-size: 12px; color: var(--ink-2); margin: 10px 0 12px; }
.legend span::before { content: ""; display: inline-block; width: 12px; height: 12px; border-radius: 3px; margin-right: 5px; vertical-align: -2px; background: #f4f6f5; border: 1px solid #ccd6cf; }
.legend .l-done::before { background: var(--green-600); border-color: var(--green-600); }
.legend .l-flag::before { box-shadow: inset 0 -4px 0 var(--amber); }
.kbd { font-size: 12px; color: var(--ink-3); margin-top: 12px; line-height: 1.7; }
kbd { background: #f1f3f2; border: 1px solid #d5ddd8; border-bottom-width: 2px; border-radius: 4px; padding: 0 5px; font-family: inherit; font-size: 11px; }
.calc { width: 260px; }
.calc .screen { background: var(--green-900); color: #fff; font-size: 1.4rem; text-align: right; padding: 10px; border-radius: 8px; min-height: 52px; word-break: break-all; font-variant-numeric: tabular-nums; }
.calc .keys { display: grid; grid-template-columns: repeat(4, 1fr); gap: 6px; margin-top: 8px; }
.calc .keys button { height: 42px; border-radius: 8px; border: 1px solid var(--line); background: #f6f8f7; font: inherit; font-weight: 700; font-size: 16px; cursor: pointer; }
.calc .keys button.op { background: var(--green-100); }
.calc .keys button.eq { background: var(--green-700); color: #fff; }

/* ---------- Results / review ---------- */
.score-hero { background: var(--green-800); color: #fff; border-radius: 14px; padding: 24px; display: flex; gap: 24px; align-items: center; flex-wrap: wrap; }
.score-big { font-size: 3rem; font-weight: 800; line-height: 1; }
.score-big small { font-size: 1.2rem; color: #b9d8c7; }
.bar { height: 10px; background: #e7ece9; border-radius: 99px; overflow: hidden; }
.bar > i { display: block; height: 100%; background: var(--green-600); border-radius: 99px; }
.bar.amber > i { background: var(--amber); }
.bar.red > i { background: var(--red); }
.rv-q { border: 1px solid var(--line); border-radius: 10px; padding: 14px 16px; background: #fff; margin-bottom: 10px; }
.rv-q .head { display: flex; gap: 8px; align-items: center; margin-bottom: 6px; font-size: 13px; font-weight: 700; color: var(--ink-2); }
.rv-opt { padding: 6px 10px; border-radius: 6px; margin: 3px 0; display: flex; gap: 8px; }
.rv-opt.correct { background: var(--green-100); color: var(--green-900); font-weight: 600; }
.rv-opt.wrong { background: var(--red-100); color: var(--red); text-decoration: line-through; }
.rv-exp { margin-top: 8px; background: var(--amber-100); border-radius: 8px; padding: 8px 12px; font-size: 14px; }

/* ---------- Notes ---------- */
.rich { line-height: 1.7; font-size: 15.5px; }
.rich h1, .rich h2, .rich h3 { margin-top: 1.2em; color: var(--green-800); }
.rich table { margin: 10px 0; border: 1px solid var(--line); }
.rich td, .rich th { border: 1px solid var(--line); }
.rich blockquote { border-left: 4px solid var(--amber); margin: 10px 0; padding: 6px 14px; background: var(--amber-100); border-radius: 0 8px 8px 0; }
.rich code { background: #f1f3f2; padding: 1px 5px; border-radius: 4px; }
.rich pre { background: #f1f3f2; padding: 12px; border-radius: 8px; overflow-x: auto; }
.note-list a { display: block; padding: 10px 12px; border-radius: 8px; text-decoration: none; color: var(--ink); border: 1px solid var(--line); background: #fff; margin-bottom: 6px; }
.note-list a:hover { border-color: var(--green-600); }

/* ---------- Admin layout ---------- */
.admin-shell { display: grid; grid-template-columns: 230px 1fr; min-height: 100vh; }
.side { background: var(--green-900); color: #cfe6d9; padding: 16px 12px; position: sticky; top: 0; height: 100vh; overflow-y: auto; }
.side .brand { padding: 4px 8px 18px; }
.side nav a { display: flex; align-items: center; gap: 10px; padding: 9px 12px; border-radius: 8px; color: #cfe6d9; text-decoration: none; font-weight: 600; font-size: 14px; margin-bottom: 2px; }
.side nav a:hover { background: rgba(255,255,255,.07); color: #fff; }
.side nav a.active { background: var(--green-700); color: #fff; }
.side nav .ico { width: 18px; text-align: center; opacity: .9; }
.admin-main { padding: 24px 28px 60px; min-width: 0; }
.admin-main > header { display: flex; align-items: center; gap: 12px; margin-bottom: 18px; flex-wrap: wrap; }
.admin-main > header h1 { margin: 0; flex: 1; }
.mobile-nav { display: none; }
@media (max-width: 860px) {
  .admin-shell { grid-template-columns: 1fr; }
  .side { display: none; }
  .side.open { display: block; position: fixed; inset: 0 30% 0 0; z-index: 40; height: 100%; }
  .mobile-nav { display: flex; align-items: center; gap: 10px; background: var(--green-900); color: #fff; padding: 10px 16px; position: sticky; top: 0; z-index: 30; }
  .admin-main { padding: 18px 16px 60px; }
}
.toolbar { display: flex; gap: 10px; flex-wrap: wrap; align-items: end; margin-bottom: 14px; }
.toolbar .field { margin: 0; min-width: 160px; }
.qprev { font-size: 14px; max-width: 520px; }
.qprev .o { color: var(--ink-2); font-size: 13px; }
.chk-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(190px, 1fr)); gap: 6px 14px; }
.hbar { display: grid; grid-template-columns: 150px 1fr 50px; gap: 10px; align-items: center; font-size: 13.5px; margin-bottom: 7px; }

/* ---------- Print ---------- */
.print-only { display: none; }
@media print {
  body { background: #fff; }
  .no-print, .topbar, .side, .mobile-nav, .tabs, .toolbar, .btn { display: none !important; }
  .print-only { display: block; }
  .admin-shell { display: block; }
  .admin-main, .wrap { padding: 0; max-width: none; }
  .card { box-shadow: none; border-color: #bbb; }
  .page-break { page-break-after: always; break-after: page; }
  .table-wrap { border: none; overflow: visible; }
}
.slip-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.slip { border: 1.5px dashed #888; border-radius: 8px; padding: 12px 14px; font-size: 14px; break-inside: avoid; }
.slip b { font-size: 15px; }
.slip .big { font-family: ui-monospace, Menlo, monospace; font-size: 16px; font-weight: 700; }
.report { max-width: 820px; margin: 0 auto; }
.report .rhead { text-align: center; border-bottom: 3px double var(--green-800); padding-bottom: 10px; margin-bottom: 14px; }
.report .rhead h2 { color: var(--green-800); margin: 0; }
@media (max-width: 600px) {
  .exam-top .inner { flex-wrap: nowrap; padding: 8px 12px; gap: 10px; }
  .exam-top .inner > div:first-child { overflow: hidden; }
  #ex-title { display: block; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; font-size: 14px; }
  .exam-top .who { display: none; }
  .timer { font-size: 1.1rem; padding: 3px 10px; }
  .qcard { padding: 16px; min-height: 0; }
  .qtext { font-size: 1.05rem; }
  .exam-body { padding: 12px 12px 30px; }
  .qnav .grow { display: none; }
  .qnav #submit { width: 100%; }
}
.wa-btn { position: fixed; right: 16px; bottom: 16px; z-index: 40; display: flex; align-items: center; gap: 6px; background: #25d366; color: #fff; text-decoration: none; font-weight: 700; padding: 10px 14px; border-radius: 99px; box-shadow: 0 6px 18px rgba(0,0,0,.2); }
body.exam .wa-btn { display: none; }
.announce { border-left: 4px solid var(--amber); }
.site-foot { text-align: center; font-size: 13px; color: var(--ink-3); padding: 20px 16px 30px; }
.site-foot a { color: var(--ink-2); margin: 0 8px; }
.rv-report { font-size: 12.5px; color: var(--ink-3); background: none; border: 0; cursor: pointer; text-decoration: underline; padding: 0; margin-top: 6px; font: inherit; }

body.noprint { -webkit-user-select: none; user-select: none; }
@media print { body.noprint > * { display: none !important; } body.noprint::after { content: "Printing has been turned off by your school."; display: block; padding: 40px; font: 16px sans-serif; } }
.seg { display: inline-flex; border: 1px solid var(--line); border-radius: 10px; overflow: hidden; background: #fff; flex-wrap: wrap; }
.seg button { border: 0; background: none; padding: 9px 14px; font: inherit; font-weight: 600; color: var(--ink-2); cursor: pointer; }
.seg button.active { background: var(--green-700); color: #fff; }
.rm-sub { border-left: 4px solid var(--green-600); }
.check-row { display: flex; gap: 10px; align-items: flex-start; padding: 8px 0; border-bottom: 1px dashed var(--line); }
.check-row:last-child { border-bottom: 0; }
/* study notes: subjects as drop-downs */
.note-acc details { border: 1px solid var(--line); border-radius: 10px; background: #fff; margin-bottom: 8px; }
.note-acc summary { cursor: pointer; padding: 11px 12px; list-style: none; display: flex; gap: 6px; align-items: center; flex-wrap: wrap; }
.note-acc summary::-webkit-details-marker { display: none; }
.note-acc summary::before { content: "▸"; color: var(--green-700); transition: transform .15s; }
.note-acc details[open] summary::before { transform: rotate(90deg); }
.note-acc .note-list { padding: 0 10px 8px; }
.note-list a.locked { color: var(--ink-3); background: var(--line, #f3f3f3); }
/* watermark + protection */
#wm { position: fixed; inset: 0; pointer-events: none; z-index: 9990; background-repeat: repeat; }
#wm.single { background-image: var(--wm-big) !important; background-repeat: no-repeat; background-position: center; background-size: min(90vw, 900px) auto; }
#wmc { position: fixed; right: 8px; bottom: 6px; font: 600 10px/1 Arial, sans-serif; color: rgba(20, 40, 30, .35); pointer-events: none; z-index: 9991; letter-spacing: .5px; }
body.protected .rich, body.protected #nbody, body.protected .qtext, body.protected .opts { -webkit-user-select: none; user-select: none; -webkit-touch-callout: none; }
body.blurred #view, body.blurred #body, body.blurred main { filter: blur(14px); transition: filter .1s; }
@media print { #wm, #wmc { display: block !important; -webkit-print-color-adjust: exact; print-color-adjust: exact; } }