*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg: #0f1117;
  --surface: #1a1d27;
  --surface2: #232638;
  --border: #2e3250;
  --accent: #4f6ef7;
  --accent-hover: #6b87ff;
  --green: #2ecc71;
  --red: #e74c3c;
  --yellow: #f39c12;
  --text: #e2e4f0;
  --text-muted: #8890b0;
  --font: 'Segoe UI', system-ui, sans-serif;
  --mono: 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
  --sidebar-w: 230px;
  --header-h: 52px;
}

html, body { height: 100%; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  font-size: 14px;
  line-height: 1.6;
}

/* ── Header ── */
.app-header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-h);
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  z-index: 100;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 20px;
  height: 100%;
  padding: 0 20px;
}

.app-title {
  font-weight: 700;
  font-size: 16px;
  letter-spacing: 0.03em;
  color: var(--accent);
}

.tab-nav { display: flex; gap: 4px; }

.tab-btn {
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 6px 16px;
  border-radius: 6px;
  cursor: pointer;
  font-size: 13px;
  font-family: var(--font);
  transition: color .15s, border-color .15s, background .15s;
}

.tab-btn:hover { color: var(--text); border-color: var(--text-muted); background: var(--surface-raised, var(--surface)); }
.tab-btn.active { color: var(--accent); border-color: var(--accent); background: rgba(79,110,247,.1); }
.source-btn { text-decoration: none; display: inline-flex; align-items: center; }

/* ── Layout ── */
main { padding-top: var(--header-h); padding-bottom: 32px; height: 100vh; }

.tab-content { height: 100%; }
.tab-content.hidden { display: none; }

/* ── Portal layout ── */
.portal-layout {
  display: flex;
  height: 100%;
}

/* ── Sidebar ── */
.event-sidebar {
  width: var(--sidebar-w);
  min-width: var(--sidebar-w);
  background: var(--surface);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 12px 0 24px;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.global-score {
  padding: 12px 16px 14px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 8px;
}

.score-label { font-size: 11px; text-transform: uppercase; letter-spacing: .06em; color: var(--text-muted); display: block; }
.score-count { font-size: 20px; font-weight: 700; display: block; margin: 2px 0 6px; }

.progress-bar {
  height: 4px;
  background: var(--border);
  border-radius: 2px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: var(--accent);
  border-radius: 2px;
  transition: width .3s ease;
}

.event-btn {
  display: block;
  width: 100%;
  text-align: left;
  background: none;
  border: none;
  border-left: 3px solid transparent;
  padding: 10px 14px;
  cursor: pointer;
  color: var(--text);
  font-family: var(--font);
  transition: background .1s, border-color .1s;
}

.event-btn:hover { background: var(--surface2); }
.event-btn.active { border-left-color: var(--accent); background: rgba(79,110,247,.08); }

.event-name { font-size: 13px; font-weight: 600; margin-bottom: 2px; }
.event-meta { display: flex; justify-content: space-between; font-size: 11px; color: var(--text-muted); margin-bottom: 5px; }
.event-score { font-weight: 600; color: var(--text); }

.reset-progress-btn {
  display: block;
  width: 100%;
  margin-top: 10px;
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 4px 0;
  border-radius: 4px;
  cursor: pointer;
  font-size: 11px;
  font-family: var(--font);
  transition: border-color .15s, color .15s;
}

.reset-progress-btn:hover { border-color: var(--red); color: var(--red); }

/* ── Detail pane ── */
.event-detail {
  flex: 1;
  overflow-y: auto;
  padding: 24px 32px 48px;
}

.placeholder {
  color: var(--text-muted);
  text-align: center;
  margin-top: 80px;
  font-size: 15px;
}

.event-header {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--border);
}

.event-title-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.event-header h2 { font-size: 22px; font-weight: 700; }

.difficulty-label, .flag-format-label {
  font-size: 12px;
  color: var(--text-muted);
  display: inline-block;
  margin-right: 12px;
}

.flash-btn {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  padding: 8px 16px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  white-space: nowrap;
  transition: background .15s;
  flex-shrink: 0;
}

.flash-btn:hover { background: var(--accent-hover); }

/* ── Challenge overview banner ── */
.challenge-overview {
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 8px;
  padding: 12px 14px 14px;
  margin-bottom: 16px;
}

.challenge-overview-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding-bottom: 10px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

.challenge-overview-title {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--accent);
}

.challenge-overview-count {
  font-size: 11px;
  color: var(--text-muted);
  margin-left: auto;
}

.challenge-overview-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

/* Shared pill base — also styles .attachment-link (see Attachments below). */
.attachment-link, .overview-chip {
  display: inline-flex;
  align-items: center;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 5px;
  font-size: 12px;
}

.attachment-link:hover, .overview-chip:hover { border-color: var(--accent); color: var(--accent); }

.overview-chip {
  gap: 6px;
  padding: 5px 11px;
  font-family: var(--font);
  color: var(--text);
  cursor: pointer;
  transition: border-color .15s, color .15s, background .15s;
}

.overview-chip:hover { background: rgba(79,110,247,.08); }

/* The ✓/□ icon inherits the chip's color (muted text → green when captured). */
.overview-chip.captured { border-color: var(--green); color: var(--green); background: rgba(46,204,113,.08); }

/* ── Challenge cards ── */
.challenges-list { display: flex; flex-direction: column; gap: 16px; }

.challenge-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  transition: border-color .15s;
}

.challenge-card.captured { border-color: var(--green); }

.challenge-header { padding: 12px 16px 10px; border-bottom: 1px solid var(--border); }

.challenge-title-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.status-icon {
  font-size: 16px;
  color: var(--text-muted);
  width: 20px;
  flex-shrink: 0;
}

.status-icon.captured { color: var(--green); }

.challenge-title {
  font-size: 15px;
  font-weight: 600;
  margin: 0;
}

.ecu-badge {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 1px 7px;
  font-size: 11px;
  font-weight: 600;
  font-family: var(--mono);
  color: var(--text-muted);
}

.tag {
  background: rgba(79,110,247,.15);
  color: var(--accent);
  border-radius: 4px;
  padding: 1px 7px;
  font-size: 11px;
  font-weight: 500;
}

.difficulty-badge {
  border-radius: 4px;
  padding: 1px 7px;
  font-size: 11px;
  font-weight: 600;
  margin-left: auto;
}

.difficulty-badge.difficulty-easy              { background: rgba(46,204,113,.15); color: var(--green); }
.difficulty-badge.difficulty-easy-medium       { background: rgba(46,204,113,.1); color: #a8e6be; }
.difficulty-badge.difficulty-medium            { background: rgba(243,156,18,.15); color: var(--yellow); }
.difficulty-badge.difficulty-medium-difficult  { background: rgba(243,156,18,.12); color: #f0c060; }
.difficulty-badge.difficulty-difficult         { background: rgba(231,76,60,.15); color: var(--red); }
.difficulty-badge.difficulty-hard              { background: rgba(231,76,60,.15); color: var(--red); }
.difficulty-badge.difficulty-medium-hard       { background: rgba(231,76,60,.12); color: #f08080; }
.difficulty-badge.difficulty-very-difficult    { background: rgba(231,76,60,.25); color: #ff6b6b; }
.difficulty-badge.difficulty-very-hard         { background: rgba(231,76,60,.25); color: #ff6b6b; }

.challenge-body { padding: 16px; display: flex; flex-direction: column; gap: 12px; }

.description { color: var(--text); }
.description p { margin-bottom: 8px; }
.description p:last-child { margin-bottom: 0; }
.description code { font-family: var(--mono); background: var(--surface2); padding: 1px 5px; border-radius: 3px; font-size: 12px; }
.description pre { background: var(--surface2); padding: 10px; border-radius: 6px; overflow-x: auto; }
.description a { color: var(--accent); }

/* Attachments */
.attachments-area { display: flex; flex-wrap: wrap; gap: 8px; }

.attachment-link {
  gap: 4px;
  padding: 4px 10px;
  font-family: var(--mono);
  color: var(--text-muted);
  text-decoration: none;
  transition: border-color .15s, color .15s;
}

.full-solution-area { display: flex; flex-direction: column; gap: 8px; }

.full-solution-btn {
  background: var(--surface2);
  border: 1px solid var(--border);
  color: var(--text-muted);
  padding: 5px 12px;
  border-radius: 5px;
  cursor: pointer;
  font-size: 12px;
  font-family: var(--font);
  transition: border-color .15s, background .15s, color .15s;
  align-self: flex-start;
}

.full-solution-btn:hover { border-color: var(--green); color: var(--green); }

.full-solution-block {
  background: var(--surface2);
  border-left: 3px solid var(--green);
  border-radius: 0 5px 5px 0;
  padding: 14px 16px;
  font-size: 13px;
  line-height: 1.7;
}

.full-solution-label {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--green);
  font-weight: 700;
  margin-bottom: 10px;
}

.full-solution-block h2 { font-size: 15px; font-weight: 700; margin: 14px 0 6px; }
.full-solution-block h3 { font-size: 13px; font-weight: 700; margin: 12px 0 4px; }
.full-solution-block p { margin-bottom: 8px; }
.full-solution-block p:last-child { margin-bottom: 0; }
.full-solution-block code { font-family: var(--mono); background: rgba(0,0,0,.3); padding: 1px 5px; border-radius: 3px; font-size: 12px; }
.full-solution-block pre { background: rgba(0,0,0,.35); padding: 10px 12px; border-radius: 6px; overflow-x: auto; margin: 8px 0; }
.full-solution-block pre code { background: none; padding: 0; font-size: 12px; }
.full-solution-block a { color: var(--accent); }
.full-solution-block ul, .full-solution-block ol { padding-left: 20px; margin-bottom: 8px; }
.full-solution-block li { margin-bottom: 3px; }
.full-solution-block table { border-collapse: collapse; width: 100%; margin: 8px 0; font-size: 12px; }
.full-solution-block th, .full-solution-block td { border: 1px solid var(--border); padding: 4px 8px; text-align: left; }
.full-solution-block th { background: rgba(79,110,247,.1); font-weight: 600; }
.full-solution-block blockquote { border-left: 2px solid var(--border); padding-left: 10px; color: var(--text-muted); margin: 6px 0; }

/* Flag area */
.flag-form {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.flag-input {
  background: var(--surface2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 6px 10px;
  border-radius: 5px;
  font-family: var(--mono);
  font-size: 13px;
  min-width: 240px;
  outline: none;
  transition: border-color .15s;
}

.flag-input:focus { border-color: var(--accent); }

.submit-btn {
  background: var(--accent);
  border: none;
  color: #fff;
  padding: 6px 14px;
  border-radius: 5px;
  cursor: pointer;
  font-size: 13px;
  font-family: var(--font);
  font-weight: 600;
  transition: background .15s;
}

.submit-btn:hover { background: var(--accent-hover); }

.flag-error { color: var(--red); font-size: 12px; }

.flag-captured {
  background: rgba(46,204,113,.1);
  border: 1px solid rgba(46,204,113,.3);
  border-radius: 5px;
  padding: 6px 12px;
  font-size: 13px;
  color: var(--green);
}

.flag-captured code { font-family: var(--mono); font-size: 12px; }
.captured-check { font-size: 15px; margin-right: 4px; }

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%       { transform: translateX(-6px); }
  40%       { transform: translateX(6px); }
  60%       { transform: translateX(-4px); }
  80%       { transform: translateX(4px); }
}

.shake { animation: shake .35s ease; }

/* ── Reset tab ── */
.reset-panel {
  max-width: 640px;
  margin: 40px auto;
  padding: 0 24px;
}

.reset-panel h2 { font-size: 20px; margin-bottom: 12px; }
.reset-panel p { color: var(--text-muted); margin-bottom: 10px; }
.reset-panel code { font-family: var(--mono); background: var(--surface2); padding: 1px 5px; border-radius: 3px; font-size: 12px; color: var(--text); }

.reset-btn {
  display: inline-block;
  margin: 16px 0 20px;
  background: var(--accent);
  border: none;
  color: #fff;
  padding: 10px 24px;
  border-radius: 7px;
  cursor: pointer;
  font-size: 14px;
  font-family: var(--font);
  font-weight: 600;
  transition: background .15s;
}

.reset-btn:hover  { background: var(--accent-hover); }
.reset-btn:disabled { opacity: .5; cursor: not-allowed; }

.serial-log {
  background: #0a0c12;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 12px;
  min-height: 120px;
  max-height: 300px;
  overflow-y: auto;
  font-family: var(--mono);
  font-size: 12px;
  margin-bottom: 16px;
}

.log-line { padding: 1px 0; }
.log-ok   { color: var(--green); }
.log-warn { color: var(--yellow); }
.log-error { color: var(--red); }

.reset-success {
  background: rgba(46,204,113,.1);
  border: 1px solid rgba(46,204,113,.3);
  border-radius: 6px;
  padding: 14px 16px;
  color: var(--green);
  line-height: 1.7;
}

.reset-success a { color: var(--accent); }

/* ── Footer ── */
.app-footer {
  position: fixed;
  bottom: 0; left: 0; right: 0;
  padding: 6px 20px;
  background: var(--surface);
  border-top: 1px solid var(--border);
  font-size: 11px;
  color: var(--text-muted);
  text-align: center;
  z-index: 100;
}

.app-footer a { color: var(--text-muted); text-decoration: underline; }
.app-footer a:hover { color: var(--text); }

/* ── Scrollbar ── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #4a4f70; }

/* ── Mobile / narrow viewports ── */
@media (max-width: 720px) {
  /* Header: let the title + tabs wrap, keep tap targets comfortable */
  .header-inner { padding: 0 12px; gap: 8px; }
  .app-title { font-size: 14px; }
  .tab-btn { padding: 8px 12px; }

  /* Stack the sidebar above the detail pane instead of side-by-side */
  .portal-layout { flex-direction: column; }

  .event-sidebar {
    width: 100%;
    min-width: 0;
    max-height: 40vh;
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding-bottom: 12px;
  }

  .event-detail { padding: 16px 16px 64px; }


  /* Flag form: let the input go full-width and the row wrap */
  .flag-input { min-width: 0; flex: 1 1 100%; }

  /* Reset tool fits the viewport */
  .reset-panel { margin: 24px auto; padding: 0 16px; }
}

/* ── Sources / citation links ─────────────────────────────────────────────── */
.sources-area {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin-top: 10px;
}
.sources-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--text-muted);
}
.source-link {
  font-size: 12px;
  color: var(--accent);
  text-decoration: none;
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 2px 8px;
  transition: border-color .1s, color .1s;
}
.source-link:hover { border-color: var(--accent); color: var(--accent-hover); }

/* ── Mermaid diagrams (rendered inside write-ups) ──────────────────────────── */
.mermaid {
  margin: 14px 0;
  padding: 12px;
  text-align: center;
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow-x: auto;
}
.mermaid svg { max-width: 100%; height: auto; }