:root {
  --navy: #13263f;
  --navy-2: #1b3555;
  --navy-3: #244568;
  --orange: #f06d3f;
  --orange-soft: #fff0ea;
  --cream: #f7f4ef;
  --paper: #ffffff;
  --ink: #172033;
  --muted: #667085;
  --line: #e3e7ed;
  --green: #198754;
  --yellow: #a66a00;
  --shadow: 0 12px 34px rgba(19, 38, 63, .11);
  --radius: 20px;
  --sidebar: 270px;
  color-scheme: light;
}

body.dark {
  --cream: #0d1726;
  --paper: #15243a;
  --ink: #f4f7fb;
  --muted: #a9b5c5;
  --line: #2c405a;
  --orange-soft: #3a241f;
  --shadow: 0 16px 40px rgba(0,0,0,.28);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--cream);
  color: var(--ink);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}
button, input, select, textarea { font: inherit; }
button { cursor: pointer; }
a { color: inherit; }

.app-shell { min-height: 100vh; display: flex; }
.sidebar {
  width: var(--sidebar);
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 20;
  display: flex;
  flex-direction: column;
  padding: 28px 18px 22px;
  background: linear-gradient(180deg, var(--navy), #0e1d31);
  color: #fff;
  overflow-y: auto;
}
.brand { display: flex; align-items: center; gap: 12px; padding: 4px 10px 28px; }
.brand strong { display: block; letter-spacing: .08em; font-size: 15px; }
.brand small { display: block; opacity: .62; font-size: 10px; letter-spacing: .17em; margin-top: 2px; }
.brand-mark { width: 38px; height: 38px; border-radius: 13px; background: rgba(255,255,255,.09); display: grid; place-content: center; gap: 3px; transform: rotate(-8deg); }
.brand-mark span { display:block; height:4px; border-radius:5px; background:var(--orange); }
.brand-mark span:nth-child(1){ width:22px; }
.brand-mark span:nth-child(2){ width:15px; }
.brand-mark span:nth-child(3){ width:9px; }
nav { display: grid; gap: 5px; }
.nav-item {
  width: 100%; border: 0; background: transparent; color: rgba(255,255,255,.72);
  display: flex; align-items: center; gap: 12px; border-radius: 13px; padding: 11px 12px; text-align: left;
  transition: .18s ease;
}
.nav-item:hover { background: rgba(255,255,255,.07); color: white; }
.nav-item.active { background: rgba(240,109,63,.17); color: white; box-shadow: inset 3px 0 var(--orange); }
.nav-icon { width: 23px; text-align:center; font-size: 17px; }
.nav-label { font-size: 13px; font-weight: 650; }
.sidebar-footer { margin-top: auto; padding: 24px 10px 0; color: rgba(255,255,255,.65); }
.mini-progress { height: 5px; border-radius: 10px; background: rgba(255,255,255,.14); overflow: hidden; margin-bottom: 8px; }
.mini-progress span { display: block; height: 100%; width: 0; background: var(--orange); transition: width .3s; }

.main-column { margin-left: var(--sidebar); width: calc(100% - var(--sidebar)); min-height: 100vh; }
.topbar {
  height: 76px; position: sticky; top: 0; z-index: 12; display:flex; align-items:center; gap:14px;
  padding: 0 34px; background: color-mix(in srgb, var(--cream) 88%, transparent); backdrop-filter: blur(18px);
  border-bottom: 1px solid color-mix(in srgb, var(--line) 75%, transparent);
}
.top-title { flex:1; }
.top-title strong { display:block; font-size:15px; }
.top-title small { color:var(--muted); font-size:12px; }
.top-actions { display:flex; align-items:center; gap:9px; }
.icon-btn, .avatar {
  border:1px solid var(--line); background:var(--paper); color:var(--ink); width:40px; height:40px; border-radius:13px;
  display:grid; place-items:center; box-shadow:0 5px 18px rgba(19,38,63,.05);
}
.icon-btn:hover, .avatar:hover { transform: translateY(-1px); box-shadow: var(--shadow); }
.avatar { background: var(--orange); border-color: var(--orange); color:white; font-weight:800; font-size:12px; }
.menu-btn { display:none; }
main { padding: 34px; max-width: 1500px; margin: 0 auto; }

.hero {
  position:relative; overflow:hidden; background:linear-gradient(135deg, var(--navy), var(--navy-3)); color:white;
  padding:38px; border-radius:28px; box-shadow:var(--shadow); min-height:255px;
}
.hero::after { content:""; position:absolute; width:320px; height:320px; border:65px solid rgba(255,255,255,.045); border-radius:50%; right:-100px; top:-105px; }
.hero-grid { display:grid; grid-template-columns: minmax(0,1.5fr) minmax(260px,.7fr); gap:28px; position:relative; z-index:1; }
.eyebrow { color:var(--orange); letter-spacing:.14em; font-weight:800; font-size:10px; }
.hero h1 { font-size:clamp(28px,4vw,49px); line-height:1.08; margin:10px 0 15px; max-width:850px; }
.hero p { color:rgba(255,255,255,.76); max-width:780px; margin:0; }
.hero-actions { display:flex; flex-wrap:wrap; gap:10px; margin-top:25px; }
.btn {
  border:0; border-radius:13px; padding:11px 16px; font-weight:750; background:var(--orange); color:white;
  display:inline-flex; align-items:center; justify-content:center; gap:8px; text-decoration:none;
}
.btn:hover { filter:brightness(1.05); transform:translateY(-1px); }
.btn.secondary { background:rgba(255,255,255,.1); border:1px solid rgba(255,255,255,.2); }
.btn.ghost { background:var(--paper); color:var(--ink); border:1px solid var(--line); }
.btn.small { padding:8px 11px; border-radius:10px; font-size:12px; }
.countdown-card { align-self:stretch; background:rgba(255,255,255,.09); border:1px solid rgba(255,255,255,.13); border-radius:20px; padding:22px; display:flex; flex-direction:column; justify-content:center; }
.countdown { display:grid; grid-template-columns:repeat(3,1fr); gap:8px; margin:15px 0; }
.countdown div { background:rgba(0,0,0,.14); border-radius:12px; padding:12px 6px; text-align:center; }
.countdown strong { display:block; font-size:23px; }
.countdown small { opacity:.65; font-size:9px; text-transform:uppercase; letter-spacing:.08em; }

.section-head { display:flex; justify-content:space-between; align-items:end; gap:20px; margin:34px 0 15px; }
.section-head h2 { margin:4px 0 0; font-size:23px; }
.section-head p { color:var(--muted); margin:0; max-width:700px; font-size:13px; }
.grid { display:grid; gap:16px; }
.grid.two { grid-template-columns:repeat(2,minmax(0,1fr)); }
.grid.three { grid-template-columns:repeat(3,minmax(0,1fr)); }
.grid.four { grid-template-columns:repeat(4,minmax(0,1fr)); }
.card {
  background:var(--paper); border:1px solid var(--line); border-radius:var(--radius); padding:22px; box-shadow:0 5px 18px rgba(19,38,63,.035);
}
.card:hover.lift { transform:translateY(-2px); box-shadow:var(--shadow); }
.card h3 { margin:0 0 8px; font-size:16px; }
.card p { margin:0; color:var(--muted); font-size:13.5px; }
.card .meta { display:flex; flex-wrap:wrap; align-items:center; gap:7px; margin-bottom:11px; }
.tag { display:inline-flex; align-items:center; gap:5px; padding:5px 9px; border-radius:99px; background:var(--orange-soft); color:var(--orange); font-size:10px; font-weight:800; letter-spacing:.03em; }
.tag.navy { background:color-mix(in srgb, var(--navy) 10%, var(--paper)); color:var(--navy-3); }
body.dark .tag.navy { color:#a8c9ed; }
.tag.green { background:color-mix(in srgb, var(--green) 12%, var(--paper)); color:var(--green); }
.metric { background:var(--paper); border:1px solid var(--line); border-radius:18px; padding:19px; }
.metric strong { font-size:25px; display:block; margin-top:4px; }
.metric small { color:var(--muted); }
.metric .metric-icon { font-size:20px; }

.callout { border-left:4px solid var(--orange); background:var(--orange-soft); border-radius:0 16px 16px 0; padding:18px 20px; }
.callout strong { display:block; margin-bottom:5px; }
.callout p { margin:0; color:var(--ink); }
.quote { font-size:18px; line-height:1.55; font-weight:650; }
.copy-row { display:flex; justify-content:space-between; align-items:start; gap:14px; }
.copy-row .btn { flex:0 0 auto; }

.tabs { display:flex; gap:8px; flex-wrap:wrap; margin-bottom:16px; }
.tab { border:1px solid var(--line); color:var(--muted); background:var(--paper); padding:8px 13px; border-radius:99px; font-size:12px; font-weight:700; }
.tab.active { background:var(--navy); color:white; border-color:var(--navy); }

.accordion { display:grid; gap:11px; }
.acc-item { background:var(--paper); border:1px solid var(--line); border-radius:17px; overflow:hidden; }
.acc-head { width:100%; border:0; background:transparent; color:var(--ink); display:flex; align-items:center; gap:12px; padding:17px 19px; text-align:left; }
.acc-head .grow { flex:1; }
.acc-head strong { display:block; font-size:14px; }
.acc-head small { color:var(--muted); }
.acc-head .chev { transition:transform .2s; }
.acc-item.open .chev { transform:rotate(180deg); }
.acc-body { display:none; border-top:1px solid var(--line); padding:18px 19px 20px; }
.acc-item.open .acc-body { display:block; }
.answer { font-size:14px; }
.answer p { margin:0 0 12px; }
.answer ul, .clean-list { margin:8px 0 0; padding-left:19px; }
.answer li, .clean-list li { margin:6px 0; }
.warning { background:color-mix(in srgb, #f5a623 11%, var(--paper)); border:1px solid color-mix(in srgb, #f5a623 26%, var(--line)); padding:12px; border-radius:12px; color:var(--ink); font-size:12px; }
.keyword-row { display:flex; flex-wrap:wrap; gap:6px; margin-top:13px; }

.step-list { position:relative; display:grid; gap:14px; }
.step { display:grid; grid-template-columns:48px 1fr; gap:14px; align-items:start; }
.step-number { width:43px; height:43px; border-radius:14px; background:var(--navy); color:white; display:grid; place-items:center; font-weight:900; }
.step h3 { margin:0 0 4px; }
.step p { margin:0; color:var(--muted); }

.timeline { display:grid; gap:15px; }
.timeline-card { display:grid; grid-template-columns:180px 1fr; gap:20px; }
.timeline-card .company { background:var(--navy); color:white; border-radius:16px; padding:18px; }
.timeline-card .company h3 { margin:0 0 5px; }
.timeline-card .company small { opacity:.7; }
.timeline-card .content { padding:3px 0; }
.timeline-card ul { margin:7px 0 12px; padding-left:18px; }
.timeline-card li { margin:4px 0; }

.filters { display:flex; flex-wrap:wrap; gap:9px; margin-bottom:17px; }
.filters select, .filters input, .notes-area {
  border:1px solid var(--line); background:var(--paper); color:var(--ink); border-radius:12px; padding:10px 12px; outline:none;
}
.filters input { min-width:240px; flex:1; }
.filters select:focus, .filters input:focus, .notes-area:focus { border-color:var(--orange); box-shadow:0 0 0 3px color-mix(in srgb, var(--orange) 13%, transparent); }

.flashcard {
  min-height:270px; perspective:1100px; cursor:pointer;
}
.flash-inner { position:relative; width:100%; min-height:270px; transition:transform .55s; transform-style:preserve-3d; }
.flashcard.flipped .flash-inner { transform:rotateY(180deg); }
.flash-front, .flash-back { position:absolute; inset:0; backface-visibility:hidden; background:var(--paper); border:1px solid var(--line); border-radius:22px; padding:28px; box-shadow:var(--shadow); display:flex; flex-direction:column; justify-content:center; }
.flash-back { transform:rotateY(180deg); }
.flash-front h2 { font-size:28px; margin:7px 0; }
.flash-back h3 { margin:0 0 12px; }
.flash-back .example { margin-top:18px; border-left:3px solid var(--orange); padding-left:13px; color:var(--muted); }
.flash-controls { display:flex; justify-content:center; gap:10px; margin-top:16px; flex-wrap:wrap; }

.practice-card { max-width:850px; margin:0 auto; }
.practice-question { font-size:clamp(22px,4vw,34px); line-height:1.3; margin:16px 0 22px; }
.timer-ring { width:75px; height:75px; border-radius:50%; background:conic-gradient(var(--orange) var(--timer, 0%), var(--line) 0); display:grid; place-items:center; }
.timer-ring::before { content:""; width:59px; height:59px; border-radius:50%; background:var(--paper); position:absolute; }
.timer-ring span { position:relative; font-weight:900; font-size:12px; }
.practice-toolbar { display:flex; justify-content:space-between; align-items:center; gap:12px; flex-wrap:wrap; }
.reveal { display:none; margin-top:19px; }
.reveal.show { display:block; }

.notes-area { width:100%; min-height:300px; resize:vertical; line-height:1.55; }
.notes-status { color:var(--muted); font-size:12px; margin-top:8px; }
.check-list { display:grid; gap:9px; }
.check-row { display:flex; gap:11px; align-items:flex-start; background:var(--paper); border:1px solid var(--line); border-radius:14px; padding:13px; }
.check-row input { margin-top:4px; accent-color:var(--orange); }
.check-row.done span { text-decoration:line-through; color:var(--muted); }

.table-wrap { overflow:auto; border:1px solid var(--line); border-radius:17px; }
table { width:100%; border-collapse:collapse; min-width:720px; background:var(--paper); }
th, td { padding:13px 15px; border-bottom:1px solid var(--line); text-align:left; vertical-align:top; font-size:13px; }
th { color:var(--muted); font-size:10px; letter-spacing:.08em; text-transform:uppercase; background:color-mix(in srgb, var(--cream) 60%, var(--paper)); }
tr:last-child td { border-bottom:0; }

.modal-backdrop { position:fixed; inset:0; z-index:50; background:rgba(5,12,22,.65); backdrop-filter:blur(8px); display:grid; place-items:center; padding:20px; }
.modal { background:var(--paper); color:var(--ink); width:min(900px,100%); max-height:90vh; overflow:auto; border-radius:25px; padding:26px; box-shadow:0 30px 80px rgba(0,0,0,.4); }
.modal-head { display:flex; justify-content:space-between; align-items:start; gap:20px; margin-bottom:20px; }
.modal-head h2 { margin:5px 0 0; }
.hidden { display:none !important; }
.toast { position:fixed; right:25px; bottom:25px; z-index:70; background:var(--navy); color:white; border-radius:12px; padding:12px 16px; box-shadow:var(--shadow); font-size:13px; }

.source-link { display:flex; align-items:center; justify-content:space-between; gap:14px; text-decoration:none; background:var(--paper); border:1px solid var(--line); border-radius:13px; padding:13px 15px; }
.source-link:hover { border-color:var(--orange); }

@media (max-width: 1050px) {
  .grid.four { grid-template-columns:repeat(2,minmax(0,1fr)); }
  .grid.three { grid-template-columns:repeat(2,minmax(0,1fr)); }
  .hero-grid { grid-template-columns:1fr; }
  .countdown-card { max-width:420px; }
}

@media (max-width: 820px) {
  .sidebar { transform:translateX(-101%); transition:transform .25s; box-shadow:20px 0 50px rgba(0,0,0,.3); }
  .sidebar.open { transform:translateX(0); }
  .main-column { margin-left:0; width:100%; }
  .menu-btn { display:grid; }
  .topbar { padding:0 17px; height:68px; }
  main { padding:18px 15px 90px; }
  .hero { padding:25px 21px; border-radius:22px; }
  .grid.two, .grid.three, .grid.four { grid-template-columns:1fr; }
  .timeline-card { grid-template-columns:1fr; }
  .timeline-card .company { padding:15px; }
  .section-head { align-items:start; flex-direction:column; gap:5px; }
}

@media (max-width: 520px) {
  .top-title small { display:none; }
  .hero h1 { font-size:29px; }
  .hero-actions .btn { width:100%; }
  .countdown strong { font-size:19px; }
  .copy-row { flex-direction:column; }
  .copy-row .btn { width:100%; }
  .filters { display:grid; grid-template-columns:1fr; }
  .filters input { min-width:0; width:100%; }
  .practice-toolbar { align-items:flex-start; }
  .modal { padding:20px 16px; border-radius:20px; }
}

@media print {
  .sidebar, .topbar, .hero-actions, .btn, .filters { display:none !important; }
  .main-column { margin:0; width:100%; }
  main { padding:0; }
  .card, .hero { box-shadow:none; break-inside:avoid; }
}