:root{
  --navy:#1F3864; --blue:#2E75B6; --green:#548235; --amber:#B5851F;
  --bg:#f4f6fb; --card:#ffffff; --ink:#1f2733; --muted:#667085; --line:#e3e8f0;
  --m1:#1F3864; --m2:#2E75B6; --m3:#9C4A1A; --m4:#548235;
  --radius:14px; --shadow:0 1px 3px rgba(20,40,80,.08),0 4px 18px rgba(20,40,80,.06);
}
*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Arial,sans-serif;background:var(--bg);color:var(--ink);line-height:1.5}
h1,h2,h3{margin:0}
.link{color:var(--blue);cursor:pointer;text-decoration:underline}

/* header */
.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;
  background:linear-gradient(120deg,var(--navy),var(--blue));color:#fff;padding:14px 22px;flex-wrap:wrap}
.brand{display:flex;align-items:center;gap:14px}
.logo{width:42px;height:42px;border-radius:12px;background:rgba(255,255,255,.18);
  display:flex;align-items:center;justify-content:center;font-weight:800;font-size:22px}
.logo-img{height:46px;width:auto;display:block;background:#fff;padding:5px 9px;border-radius:10px}
.topbar h1{font-size:20px;font-weight:700}
.sub{margin:2px 0 0;font-size:12.5px;opacity:.85}
.countdown{display:flex;gap:8px;flex-wrap:wrap}
.cd-pill{background:rgba(255,255,255,.14);border-radius:10px;padding:6px 10px;font-size:12px;text-align:center;min-width:78px}
.cd-pill b{display:block;font-size:16px}
.cd-pill.soon{background:rgba(255,210,120,.30)}

/* tabs */
.tabs{display:flex;gap:4px;overflow-x:auto;background:#fff;padding:8px 14px;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}
.tabs button{border:0;background:transparent;padding:9px 14px;border-radius:10px;font-size:14px;font-weight:600;color:var(--muted);cursor:pointer;white-space:nowrap}
.tabs button:hover{background:var(--bg)}
.tabs button.active{background:var(--navy);color:#fff}

main{max-width:980px;margin:0 auto;padding:22px 16px 40px}
.foot{max-width:980px;margin:0 auto;padding:18px 16px 40px;color:var(--muted);font-size:12.5px;text-align:center}

.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow);padding:18px;margin-bottom:16px}
.row{display:flex;gap:12px;flex-wrap:wrap;align-items:center}
.spacer{flex:1}
.muted{color:var(--muted)}
.small{font-size:12.5px}
.center{text-align:center}

/* buttons */
button.btn,a.btn{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line);background:#fff;color:var(--ink);
  padding:8px 13px;border-radius:10px;font-size:13.5px;font-weight:600;cursor:pointer;text-decoration:none}
button.btn:hover,a.btn:hover{border-color:var(--blue);color:var(--blue)}
.btn.primary{background:var(--navy);color:#fff;border-color:var(--navy)}
.btn.primary:hover{background:var(--blue);border-color:var(--blue);color:#fff}
.btn.ghost{background:transparent}
.btn.sm{padding:5px 9px;font-size:12.5px}
.btn:disabled{opacity:.45;cursor:default}

/* phase + module chips */
.chip{display:inline-block;padding:3px 9px;border-radius:999px;font-size:11.5px;font-weight:700;color:#fff}
.phase{background:var(--blue)}
.phase.light{background:var(--amber)}
.phase.exam{background:#c0392b}
.mtag{font-weight:700}
.m1{color:var(--m1)} .m2{color:var(--m2)} .m3{color:var(--m3)} .m4{color:var(--m4)}
.dotbar{height:5px;border-radius:5px;margin:-18px -18px 14px;border-top-left-radius:14px;border-top-right-radius:14px}

/* today */
.daynav{display:flex;align-items:center;gap:10px;margin-bottom:14px;flex-wrap:wrap}
.daynav select{padding:8px;border-radius:9px;border:1px solid var(--line);font-size:14px}
.tip{background:#eef5ec;border-left:4px solid var(--green);padding:11px 14px;border-radius:8px;color:#2e4a22;font-size:14px;margin:12px 0}
.task{display:flex;gap:11px;align-items:flex-start;padding:11px 0;border-top:1px solid var(--line)}
.task:first-of-type{border-top:0}
.task input[type=checkbox]{width:20px;height:20px;margin-top:2px;flex:none;accent-color:var(--navy)}
.task .tbody{flex:1}
.task .acts{display:flex;gap:7px;flex-wrap:wrap;margin-top:7px}
.done-text{text-decoration:line-through;color:var(--muted)}

/* plan list */
.planday{display:flex;gap:12px;align-items:center;padding:9px 12px;border:1px solid var(--line);border-radius:10px;margin-bottom:7px;cursor:pointer;background:#fff}
.planday:hover{border-color:var(--blue)}
.planday.now{border-color:var(--navy);box-shadow:0 0 0 2px rgba(31,56,100,.15)}
.planday .dn{font-weight:800;color:var(--navy);min-width:54px}
.planday .pd-date{min-width:78px;font-size:13px}
.planday .pd-phase{font-size:12px}
.weekhdr{font-weight:800;color:var(--navy);margin:16px 0 8px;font-size:15px}

/* flashcards */
.fc-wrap{max-width:620px;margin:0 auto}
.flashcard{perspective:1400px;height:300px;margin:14px 0;cursor:pointer}
.fc-inner{position:relative;width:100%;height:100%;transition:transform .5s;transform-style:preserve-3d}
.flashcard.flipped .fc-inner{transform:rotateY(180deg)}
.fc-face{position:absolute;inset:0;backface-visibility:hidden;border-radius:16px;border:1px solid var(--line);
  display:flex;flex-direction:column;align-items:center;justify-content:center;padding:26px;text-align:center;box-shadow:var(--shadow);background:#fff}
.fc-face .lbl{position:absolute;top:12px;left:16px;font-size:11px;font-weight:700;letter-spacing:.5px;text-transform:uppercase;color:var(--muted)}
.fc-front{font-size:21px;font-weight:700;color:var(--navy)}
.fc-back{transform:rotateY(180deg);font-size:17px;color:var(--ink);background:#fbfcff}
.fc-controls{display:flex;gap:8px;justify-content:center;flex-wrap:wrap;margin-top:6px}
.fc-meta{text-align:center;color:var(--muted);font-size:13px;margin-top:6px}

/* mcq */
.mcq-q{margin:14px 0;padding:14px;border:1px solid var(--line);border-radius:12px}
.mcq-q .qtext{font-weight:600;margin-bottom:8px}
.opt{display:block;padding:9px 12px;border:1px solid var(--line);border-radius:9px;margin:6px 0;cursor:pointer;font-size:14px}
.opt:hover{border-color:var(--blue)}
.opt.sel{border-color:var(--navy);background:#eef2fa}
.opt.correct{border-color:var(--green);background:#eaf5e4}
.opt.wrong{border-color:#c0392b;background:#fbe9e7}
.expl{font-size:13px;color:var(--muted);margin-top:7px;padding-left:4px}
.scorebox{font-size:18px;font-weight:800}

/* long answers */
.la-q{font-weight:700;color:var(--navy);font-size:16px;margin-bottom:6px}
textarea.la{width:100%;min-height:230px;border:1px solid var(--line);border-radius:10px;padding:12px;font-size:14.5px;font-family:inherit;resize:vertical}
.model{background:#f7f9fd;border:1px solid var(--line);border-radius:10px;padding:14px;margin-top:12px}
.model ul{margin:8px 0 0;padding-left:20px}
.model li{margin:4px 0;font-size:14px}
.timer{font-variant-numeric:tabular-nums;font-weight:800;font-size:18px;color:var(--navy)}

/* material */
.lec{display:flex;gap:10px;align-items:center;padding:8px 11px;border:1px solid var(--line);border-radius:9px;margin-bottom:6px;cursor:pointer;background:#fff;font-size:14px}
.lec:hover{border-color:var(--blue)}
.lec .num{font-weight:800;color:var(--muted);min-width:26px;text-align:center}
.viewer{width:100%;height:78vh;border:1px solid var(--line);border-radius:10px;margin-top:10px}
.search{width:100%;padding:10px 12px;border:1px solid var(--line);border-radius:10px;font-size:14px;margin-bottom:10px}

/* progress */
.bar{height:12px;background:#eef1f7;border-radius:7px;overflow:hidden}
.bar > i{display:block;height:100%;background:var(--green)}
.statgrid{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:12px}
.stat{padding:14px;border:1px solid var(--line);border-radius:12px;text-align:center}
.stat b{display:block;font-size:26px;color:var(--navy)}

.modtabs{display:flex;gap:6px;flex-wrap:wrap;margin-bottom:12px}
.modtabs button{border:1px solid var(--line);background:#fff;border-radius:999px;padding:6px 13px;font-size:13px;font-weight:600;cursor:pointer}
.modtabs button.active{color:#fff}
.modtabs button[data-m="0"].active{background:var(--navy);border-color:var(--navy)}
.modtabs button[data-m="1"].active{background:var(--m1);border-color:var(--m1)}
.modtabs button[data-m="2"].active{background:var(--m2);border-color:var(--m2)}
.modtabs button[data-m="3"].active{background:var(--m3);border-color:var(--m3)}
.modtabs button[data-m="4"].active{background:var(--m4);border-color:var(--m4)}

/* ---------- graphical lift ---------- */
.chip{box-shadow:0 1px 2px rgba(0,0,0,.12)}
.topicchip{background:#eef2f8;color:#33415c;max-width:60%;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.fc-topic{margin:10px 0 0}
/* colourful flashcard faces keyed to the module colour (--mc) */
.fc-front{border-top:6px solid var(--mc,var(--navy));background:linear-gradient(180deg,#ffffff 0%,#f5f8ff 100%)}
.fc-back{border-top:6px solid var(--mc,var(--green));background:linear-gradient(180deg,#fbfdff 0%,#eef4ff 100%)}
.fc-face .lbl{color:var(--mc,var(--muted));opacity:.85}
.flashcard{box-shadow:0 8px 26px rgba(20,40,80,.10)}
/* smooth, subtle interactions */
button.btn,a.btn,.modtabs button,.planday,.lec,.tabs button{transition:transform .12s ease,box-shadow .12s ease,border-color .12s ease,background .12s ease}
button.btn:hover,a.btn:hover{transform:translateY(-1px)}
.planday:hover,.lec:hover{transform:translateY(-1px);box-shadow:var(--shadow)}
.btn.primary{box-shadow:0 2px 8px rgba(31,56,100,.25)}
.tabs button.active{box-shadow:0 2px 8px rgba(31,56,100,.25)}
/* gentle colour wash on the progress stats */
.stat{background:linear-gradient(180deg,#ffffff,#f4f8ff)}
.stat b{background:linear-gradient(90deg,var(--navy),var(--blue));-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
/* sync status pill in footer */
.sync{display:inline-block;padding:2px 9px;border-radius:999px;background:#eef2f8;color:var(--muted)}
.sync.ok{background:#e7f3e1;color:#2e7d32}
.sync.warn{background:#fdf1dc;color:#9a6a12}
.foot .sep{opacity:.5;margin:0 2px}

/* ---------- responsive / mobile ---------- */
/* prevent iOS auto-zoom by keeping form text >=16px, and smooth touch scroll */
.tabs{-webkit-overflow-scrolling:touch}

/* respect the iPhone notch / safe areas when launched as a home-screen app */
@supports(padding:env(safe-area-inset-top)){
  .topbar{padding-top:calc(14px + env(safe-area-inset-top))}
  .tabs{padding-left:calc(14px + env(safe-area-inset-left));padding-right:calc(14px + env(safe-area-inset-right))}
  .foot{padding-bottom:calc(40px + env(safe-area-inset-bottom))}
}

@media(max-width:760px){
  main{padding:16px 12px 36px}
  .card{padding:15px}
  .topbar{padding:12px 14px}
  .viewer{height:70vh}
}

@media(max-width:560px){
  /* header stacks, logo + title shrink, countdown scrolls on its own row */
  .topbar{flex-direction:column;align-items:flex-start;gap:10px}
  .topbar h1{font-size:17px}
  .sub{font-size:11.5px}
  .logo-img{height:40px}
  .countdown{width:100%;overflow-x:auto;flex-wrap:nowrap;padding-bottom:2px}
  .cd-pill{min-width:72px;flex:0 0 auto}

  /* tabs wrap so every section is tappable without hidden side-scroll */
  .tabs{flex-wrap:wrap;overflow:visible;gap:6px;padding:8px 10px}
  .tabs button{flex:1 1 auto;white-space:normal;text-align:center;padding:9px 10px;font-size:13px}

  /* bigger, finger-friendly controls; 16px inputs = no iOS zoom */
  button.btn,a.btn{padding:10px 14px;font-size:14px}
  .btn.sm{padding:8px 11px;font-size:13px}
  input,select,textarea,.search{font-size:16px !important}
  .task input[type=checkbox]{width:24px;height:24px}

  /* flashcards: replace 3D flip with show/hide so cards size to their text */
  .flashcard{height:auto;perspective:none}
  .fc-inner{transform:none !important;min-height:200px}
  .fc-face{position:relative;inset:auto;backface-visibility:visible;min-height:200px;transform:none !important}
  .fc-back{display:none}
  .flashcard.flipped .fc-front{display:none}
  .flashcard.flipped .fc-back{display:flex}
  .fc-front{font-size:19px}
  .fc-back{font-size:16px}

  /* plan rows wrap neatly */
  .planday{flex-wrap:wrap}
  .planday .pd-date{min-width:auto}
  .statgrid{grid-template-columns:1fr 1fr}
}

@media(max-width:380px){
  .tabs button{flex:1 1 40%}
  .statgrid{grid-template-columns:1fr}
}