@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;500;600;700&family=Sora:wght@400;600;700&display=swap');

/* ── RESET & BASE ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* ── DESIGN TOKENS ── */
:root {
  --font-body: 'Outfit', -apple-system, sans-serif;
  --font-display: 'Sora', -apple-system, sans-serif;

  /* Light theme */
  --bg:            #F7F7F5;
  --bg2:           #EFEFEC;
  --surface:       #FFFFFF;
  --surface2:      #F4F4F0;
  --border:        #E2E2DC;
  --border-strong: #C8C8C0;

  --text:    #18181A;
  --text2:   #5A5A62;
  --text3:   #9A9AA8;

  --accent:       #3D6FFF;
  --accent-light: #EEF2FF;
  --accent-dim:   #C7D3FF;

  --got-text: #1A7A52;
  --got-bg:   #EDFAF3;
  --got-border: #A7E0C5;

  --nope-text: #B5341A;
  --nope-bg:   #FFF0EE;
  --nope-border: #F5B8AF;

  --flip-text:   #3D6FFF;
  --flip-bg:     #EEF2FF;
  --flip-border: #C7D3FF;

  --note-bg:    #F0F7FF;
  --note-text:  #1D5FAE;
  --note-border:#C0D8F5;

  --prog-bg:   #E5E5E0;
  --prog-fill: #3D6FFF;
  --prog-got:  #2EC87A;

  --card-front-bg:     #FFFFFF;
  --card-front-border: #E2E2DC;
  --card-back-bg:      #F0F5FF;
  --card-back-border:  #C7D3FF;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.06), 0 1px 2px rgba(0,0,0,.04);
  --shadow-md: 0 4px 16px rgba(0,0,0,.08), 0 2px 6px rgba(0,0,0,.04);
  --shadow-lg: 0 12px 40px rgba(0,0,0,.10), 0 4px 12px rgba(0,0,0,.05);
  --shadow-card: 0 2px 8px rgba(0,0,0,.05), 0 8px 32px rgba(0,0,0,.06);
  --shadow-card-hover: 0 4px 16px rgba(61,111,255,.12), 0 12px 40px rgba(0,0,0,.10);

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 26px;

  --transition: 0.2s cubic-bezier(.4,0,.2,1);
  --transition-slow: 0.4s cubic-bezier(.4,0,.2,1);
}

/* ── DARK THEME ── */
body.dark {
  --bg:            #0E0E12;
  --bg2:           #16161C;
  --surface:       #1C1C24;
  --surface2:      #22222C;
  --border:        #2E2E3C;
  --border-strong: #40405A;

  --text:    #F2F2F8;
  --text2:   #9090A8;
  --text3:   #58586A;

  --accent:       #6691FF;
  --accent-light: #111630;
  --accent-dim:   #243060;

  --got-text:  #3DE890;
  --got-bg:    #0A2218;
  --got-border:#1A5A38;

  --nope-text:  #FF8070;
  --nope-bg:    #220C08;
  --nope-border:#5A2010;

  --flip-text:   #6691FF;
  --flip-bg:     #111630;
  --flip-border: #243060;

  --note-bg:    #0E1E38;
  --note-text:  #7AAEF8;
  --note-border:#1E3E68;

  --prog-bg:   #2A2A3A;
  --prog-fill: #6691FF;
  --prog-got:  #2EC87A;

  --card-front-bg:     #1C1C24;
  --card-front-border: #2E2E3C;
  --card-back-bg:      #111628;
  --card-back-border:  #243060;

  --shadow-sm: 0 1px 3px rgba(0,0,0,.3);
  --shadow-md: 0 4px 16px rgba(0,0,0,.4);
  --shadow-lg: 0 12px 40px rgba(0,0,0,.5);
  --shadow-card: 0 2px 8px rgba(0,0,0,.3), 0 8px 32px rgba(0,0,0,.3);
  --shadow-card-hover: 0 4px 16px rgba(102,145,255,.2), 0 12px 40px rgba(0,0,0,.5);
}

/* ── GLOBAL ── */
html { -webkit-text-size-adjust: 100%; }

body {
  font-family: var(--font-body);
  background: var(--bg);
  min-height: 100vh;
  color: var(--text);
  transition: background var(--transition-slow), color var(--transition-slow);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

/* ── DARK TOGGLE ── */
.dark-toggle {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 99px;
  color: var(--text2);
  font-size: 14px;
  padding: 6px 12px;
  cursor: pointer;
  transition: background var(--transition), border-color var(--transition);
  position: absolute;
  right: 0;
  top: 50%;
  transform: translateY(-50%);
  line-height: 1;
}
.dark-toggle:hover { background: var(--border); }

/* ── PAGE HEADER (chapter pages) ── */
.page-header {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 4px;
  padding: 0 44px;
  min-height: 40px;
}

h1 {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  text-align: center;
  letter-spacing: -0.02em;
}

.subtitle {
  font-size: 12px;
  color: var(--text3);
  text-align: center;
  margin-bottom: 1rem;
  font-weight: 400;
}

/* ── BACK LINK ── */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 12px;
  font-weight: 500;
  color: var(--text3);
  text-decoration: none;
  padding: 4px 0;
  transition: color var(--transition);
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
}
.back-link:hover { color: var(--accent); }

/* ── PROGRESS BAR ── */
.top-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 0.875rem;
}
.progress-bar {
  flex: 1;
  height: 5px;
  background: var(--prog-bg);
  border-radius: 99px;
  overflow: hidden;
}
.progress-fill {
  height: 100%;
  background: var(--prog-fill);
  border-radius: 99px;
  transition: width 0.4s ease;
}
.prog-text {
  font-size: 12px;
  font-weight: 600;
  color: var(--text3);
  min-width: 52px;
  text-align: right;
}

/* ── SCORE PILLS ── */
.score-row {
  display: flex;
  gap: 6px;
  justify-content: center;
  margin-bottom: 0.875rem;
  flex-wrap: wrap;
}
.pill {
  font-size: 11px;
  font-weight: 600;
  padding: 4px 12px;
  border-radius: 99px;
  letter-spacing: 0.02em;
}
.p-got  { background: var(--got-bg);  color: var(--got-text);  border: 1px solid var(--got-border); }
.p-nope { background: var(--nope-bg); color: var(--nope-text); border: 1px solid var(--nope-border); }
.p-left { background: var(--accent-light); color: var(--accent); border: 1px solid var(--accent-dim); }

/* ── FILTER PILLS ── */
.filter-row {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 0.875rem;
}
.fb {
  font-size: 11px;
  font-weight: 500;
  padding: 5px 12px;
  border-radius: 99px;
  border: 1px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  color: var(--text2);
  white-space: nowrap;
  transition: background var(--transition), color var(--transition), border-color var(--transition), transform 0.1s;
  touch-action: manipulation;
}
.fb:active { transform: scale(0.96); }
.fb.active {
  background: var(--text);
  color: var(--bg);
  border-color: var(--text);
}
.fb-sub {
  font-size: 10px;
  padding: 4px 10px;
  opacity: 0.85;
}
.fb-sub.active { opacity: 1; }

/* ── FLASHCARD ── */
.card-area {
  perspective: 1400px;
  max-width: 600px;
  margin: 0 auto 0.875rem;
}

.card-wrap {
  width: 100%;
  min-height: 230px;
  cursor: pointer;
  -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
}

.card-inner {
  position: relative;
  width: 100%;
  min-height: 230px;
  transform-style: preserve-3d;
  transition: transform 0.45s cubic-bezier(.4,0,.2,1);
}
.card-inner.flipped { transform: rotateY(180deg); }

.face {
  position: absolute;
  width: 100%;
  min-height: 230px;
  backface-visibility: hidden;
  -webkit-backface-visibility: hidden;
  border-radius: var(--radius-xl);
  padding: 1.5rem 1.375rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  transition: background var(--transition-slow), border-color var(--transition-slow);
  box-shadow: var(--shadow-card);
}
.front {
  background: var(--card-front-bg);
  border: 1px solid var(--card-front-border);
}
.back {
  background: var(--card-back-bg);
  border: 1px solid var(--card-back-border);
  transform: rotateY(180deg);
}

/* card text */
.face-tag {
  font-size: 10px;
  font-weight: 600;
  color: var(--text3);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 10px;
}
.face-main {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  line-height: 1.6;
  margin-bottom: 8px;
  white-space: pre-line;
}
.face-sub {
  font-size: 12px;
  color: var(--text2);
  line-height: 1.55;
  white-space: pre-line;
}
.face-hint {
  font-size: 11px;
  color: var(--text3);
  margin-top: 14px;
  text-align: center;
  letter-spacing: 0.03em;
}
.face-note {
  font-size: 12px;
  color: var(--note-text);
  background: var(--note-bg);
  border: 1px solid var(--note-border);
  border-radius: var(--radius-sm);
  padding: 9px 12px;
  margin-top: 12px;
  line-height: 1.55;
}

/* cat badge */
.cat-badge {
  display: inline-block;
  font-size: 10px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 99px;
  margin-bottom: 10px;
  letter-spacing: 0.04em;
}

/* ── NAV BAR (prev / grid / next) ── */
#card-nav {
  display: flex;
  gap: 8px;
  align-items: center;
  justify-content: center;
  max-width: 600px;
  margin: 0 auto 0.75rem;
}
.nav-btn {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  padding: 10px 16px;
  min-height: 44px;
  min-width: 80px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  transition: opacity var(--transition), background var(--transition);
}
.nav-btn:not(:disabled):hover { background: var(--surface2); }
.nav-btn:disabled { opacity: 0.25; cursor: default; }
.nav-grid-btn {
  flex: 1;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 600;
  padding: 10px 12px;
  min-height: 44px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text2);
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  transition: background var(--transition);
}
.nav-grid-btn:hover { background: var(--surface2); }

/* ── ACTION BUTTONS ── */
.btn-flip {
  display: block;
  width: 100%;
  max-width: 600px;
  margin: 0 auto 0.75rem;
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 600;
  padding: 13px;
  min-height: 50px;
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--flip-border);
  background: var(--flip-bg);
  color: var(--flip-text);
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  transition: background var(--transition), border-color var(--transition), transform 0.1s;
  letter-spacing: 0.01em;
}
.btn-flip:active { transform: scale(0.99); }

.btn-row {
  display: flex;
  gap: 10px;
  justify-content: center;
  max-width: 600px;
  margin: 0 auto 0.875rem;
  padding: 0 2px;
}
.btn {
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 600;
  padding: 14px 20px;
  min-height: 52px;
  border-radius: var(--radius-lg);
  border: 1.5px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  flex: 1;
  color: var(--text);
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  transition: background var(--transition), border-color var(--transition), transform 0.1s;
}
.btn:active { transform: scale(0.98); }
.btn-got  {
  border-color: var(--got-border);
  color: var(--got-text);
  background: var(--got-bg);
}
.btn-nope {
  border-color: var(--nope-border);
  color: var(--nope-text);
  background: var(--nope-bg);
}
.btn-got:active  { background: var(--got-bg); }
.btn-nope:active { background: var(--nope-bg); }

/* ── DONE SCREEN ── */
.done-screen {
  text-align: center;
  padding: 2rem 1rem 3rem;
  max-width: 400px;
  margin: 0 auto;
}
.done-screen h2 {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text);
  letter-spacing: -0.02em;
}
.done-screen p {
  color: var(--text2);
  font-size: 13px;
  margin-bottom: 1.25rem;
  line-height: 1.6;
}
.restart-btn {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  padding: 11px 26px;
  border-radius: var(--radius-md);
  border: 1.5px solid var(--border);
  background: var(--surface);
  cursor: pointer;
  color: var(--text);
  transition: background var(--transition), border-color var(--transition);
}
.restart-btn:hover { background: var(--surface2); }

/* ── GRID OVERLAY ── */
#grid-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  z-index: 900;
}
#grid-overlay.active { display: block; }

#grid-panel {
  position: fixed;
  top: 0;
  right: -100%;
  width: min(88vw, 320px);
  height: 100%;
  background: var(--surface);
  border-left: 1px solid var(--border);
  z-index: 901;
  transition: right 0.3s cubic-bezier(.4,0,.2,1);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}
#grid-panel.active { right: 0; }

.grid-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 16px 14px;
  border-bottom: 1px solid var(--border);
}
#grid-title {
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
}
.grid-close-btn {
  background: var(--surface2);
  border: 1px solid var(--border);
  font-size: 14px;
  color: var(--text2);
  cursor: pointer;
  padding: 4px 9px;
  border-radius: var(--radius-sm);
  touch-action: manipulation;
  line-height: 1.4;
}

.grid-legend {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  padding: 10px 16px;
  font-size: 10px;
  font-weight: 500;
  color: var(--text3);
  border-bottom: 1px solid var(--border);
  letter-spacing: 0.03em;
}
.gl-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-right: 3px;
  vertical-align: middle;
}
.gl-unseen { background: var(--prog-bg); }
.gl-got    { background: var(--prog-got); }
.gl-nope   { background: #E05020; }
.gl-cur    { background: var(--prog-fill); }

#grid-dots {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 54px));
  gap: 10px;
  padding: 16px;
  overflow-y: auto;
  flex: 1;
  justify-content: start;
  -webkit-overflow-scrolling: touch;
}
.grid-dot {
  width: 100%;
  max-width: 54px;
  aspect-ratio: 1;
  border-radius: 50%;
  border: none;
  background: var(--surface2);
  color: var(--text3);
  font-size: 11px;
  font-weight: 700;
  cursor: pointer;
  touch-action: manipulation;
  -webkit-tap-highlight-color: transparent;
  transition: transform 0.1s, background 0.15s;
  display: flex;
  align-items: center;
  justify-content: center;
}
.grid-dot:active { transform: scale(0.9); }
.gd-cur  { background: var(--prog-fill); color: #fff; }
.gd-got  { background: var(--prog-got); color: #fff; }
.gd-nope { background: #E05020; color: #fff; }

/* ── WIP BADGE ── */
.wip-badge {
  display: inline-block;
  font-size: 10px;
  font-weight: 600;
  background: #FFF3DA;
  color: #7a4b00;
  border-radius: 99px;
  padding: 2px 8px;
  margin-left: 6px;
  vertical-align: middle;
}
body.dark .wip-badge { background: #221400; color: #e0b050; }

/* ── CATEGORY BADGE COLOURS — GIC ── */
.c-disp { background:#FFF1E0; color:#7A3D00; }
.c-hydro { background:#E8F5E0; color:#2E6010; }
.c-heat  { background:#FFEDEC; color:#A02020; }
.c-redox { background:#EEECFF; color:#3830A0; }
.c-misc  { background:#E0F6F0; color:#0A5040; }
.c-acid  { background:#FAEAE0; color:#7A2010; }
.c-dehy  { background:#F0EEE8; color:#5A5840; }
body.dark .c-disp { background:#2A1800; color:#F0A040; }
body.dark .c-hydro{ background:#0A2008; color:#60C040; }
body.dark .c-heat { background:#280808; color:#E06060; }
body.dark .c-redox{ background:#100E3A; color:#9888F8; }
body.dark .c-misc { background:#041A10; color:#40C890; }
body.dark .c-acid { background:#200A06; color:#E08060; }
body.dark .c-dehy { background:#18180E; color:#A0A080; }

/* ── QA CATION BADGES ── */
.c-qa-grp1 { background:#E4F2FC; color:#0B4A78; }
.c-qa-grp2a{ background:#FFF0DC; color:#633806; }
.c-qa-grp2b{ background:#FFF5DC; color:#7A4B00; }
.c-qa-grp3 { background:#EDEAFF; color:#3A3098; }
.c-qa-grp4 { background:#E6F5E0; color:#306010; }
.c-qa-grp5 { background:#FAE8E0; color:#722010; }
.c-qa-grp6 { background:#DCF8F0; color:#086040; }
.c-qa-grp7 { background:#F5F0FF; color:#5B3D9E; }
.c-qa-nh4  { background:#FFF0F8; color:#8A2060; }
.c-qa-pb   { background:#E4F2FC; color:#0B4A78; }
.c-qa-ag   { background:#F5F5E4; color:#585800; }
.c-qa-hg2  { background:#F2E8FC; color:#5A2080; }
body.dark .c-qa-grp1 { background:#081828; color:#70B8E8; }
body.dark .c-qa-grp2a{ background:#2A1808; color:#E8A050; }
body.dark .c-qa-grp2b{ background:#221400; color:#E0B050; }
body.dark .c-qa-grp3 { background:#120E3A; color:#A088F0; }
body.dark .c-qa-grp4 { background:#0A2008; color:#70C050; }
body.dark .c-qa-grp5 { background:#220A06; color:#E08870; }
body.dark .c-qa-grp6 { background:#061A12; color:#48D098; }
body.dark .c-qa-grp7 { background:#180C30; color:#B088F0; }
body.dark .c-qa-nh4  { background:#280A18; color:#E078B0; }
body.dark .c-qa-pb   { background:#081828; color:#70B0E0; }
body.dark .c-qa-ag   { background:#181810; color:#C0C038; }
body.dark .c-qa-hg2  { background:#180828; color:#C080E8; }

/* ── P-BLOCK BADGES ── */
.c-pb13 { background:#E4F2FC; color:#0E4F7A; }
.c-pb14 { background:#E8F4DE; color:#3B6D11; }
.c-pb15 { background:#FAF0DA; color:#633806; }
.c-pb16 { background:#FAE8E0; color:#712B13; }
.c-pb17 { background:#EEEEFF; color:#3C3499; }
.c-pb18 { background:#DCFAF0; color:#085041; }
body.dark .c-pb13 { background:#081828; color:#70B0E0; }
body.dark .c-pb14 { background:#0E2210; color:#70C050; }
body.dark .c-pb15 { background:#2A1808; color:#E8A050; }
body.dark .c-pb16 { background:#220A06; color:#E09070; }
body.dark .c-pb17 { background:#10103A; color:#A090F8; }
body.dark .c-pb18 { background:#061A14; color:#50D0A0; }

/* ── D&F BLOCK BADGES ── */
.c-db-ov   { background:#E4F2FC; color:#0E4F7A; }
.c-db-prop { background:#FAF0DA; color:#633806; }
.c-db-cat  { background:#E8F4DE; color:#3B6D11; }
.c-db-cmpd { background:#EEEEFF; color:#3C3499; }
.c-fb-ov   { background:#FAE8E0; color:#712B13; }
.c-fb-ln   { background:#DCFAF0; color:#085041; }
.c-fb-ac   { background:#F5F0FF; color:#5B3D9E; }
body.dark .c-db-ov   { background:#081828; color:#70B0E0; }
body.dark .c-db-prop { background:#2A1808; color:#E8A050; }
body.dark .c-db-cat  { background:#0E2210; color:#70C050; }
body.dark .c-db-cmpd { background:#10103A; color:#A090F8; }
body.dark .c-fb-ov   { background:#220A06; color:#E09070; }
body.dark .c-fb-ln   { background:#061A14; color:#50D0A0; }
body.dark .c-fb-ac   { background:#180C30; color:#B090F0; }

/* ── CH5 ANION BADGES ── */
.c-an-ov   { background:#EEF5FF; color:#1A4A80; }
.c-an-se   { background:#FFFAEC; color:#6B4200; }
.c-an-sol  { background:#F3EFFE; color:#4A2A90; }
.c-an-dil  { background:#EAFAF2; color:#0A5A30; }
.c-an-co3  { background:#E4F2FC; color:#0E4F7A; }
.c-an-s2   { background:#FFF5DA; color:#7A4B00; }
.c-an-no2  { background:#FAE8E0; color:#712B13; }
.c-an-conc { background:#FFF0F0; color:#8A1A1A; }
.c-an-cl   { background:#E8F5DE; color:#2A5A10; }
.c-an-br   { background:#FAF0DA; color:#633806; }
.c-an-i    { background:#F4EFFE; color:#4A1A8A; }
.c-an-no3  { background:#FAE8E0; color:#8A3010; }
.c-an-ox   { background:#E0FFF0; color:#0A5A40; }
.c-an-so4  { background:#F0F0FF; color:#2A2A8A; }
body.dark .c-an-ov   { background:#081828; color:#70B0E8; }
body.dark .c-an-se   { background:#221400; color:#D0A040; }
body.dark .c-an-sol  { background:#14083A; color:#B08AF0; }
body.dark .c-an-dil  { background:#061A10; color:#50D080; }
body.dark .c-an-co3  { background:#081830; color:#70B8E8; }
body.dark .c-an-s2   { background:#221400; color:#E0B050; }
body.dark .c-an-no2  { background:#220808; color:#E09070; }
body.dark .c-an-conc { background:#280808; color:#F08080; }
body.dark .c-an-cl   { background:#0E2208; color:#80D050; }
body.dark .c-an-br   { background:#2A1808; color:#E8A050; }
body.dark .c-an-i    { background:#180830; color:#C088F0; }
body.dark .c-an-no3  { background:#280E08; color:#F0A070; }
body.dark .c-an-ox   { background:#061A14; color:#50D0A0; }
body.dark .c-an-so4  { background:#0E0E30; color:#9090F8; }

/* ── CH6 S-BLOCK BADGES (if any) ── */
.c-h2    { background:#E4F2FC; color:#0E4F7A; }
.c-h2o2  { background:#EEEEFF; color:#3C3499; }
.c-li    { background:#E8F4DE; color:#3B6D11; }
.c-na    { background:#FAF0DA; color:#633806; }
.c-k     { background:#FAE8E0; color:#712B13; }
.c-be    { background:#DCFAF0; color:#085041; }
.c-mg    { background:#F5F0FF; color:#5B3D9E; }
.c-ca    { background:#EEF5FF; color:#1A4A80; }
.c-s1    { background:#E8F4DE; color:#3B6D11; }
.c-s2b   { background:#FAF0DA; color:#633806; }
body.dark .c-h2   { background:#081828; color:#70B0E0; }
body.dark .c-h2o2 { background:#10103A; color:#A090F8; }
body.dark .c-li   { background:#0E2210; color:#70C050; }
body.dark .c-na   { background:#2A1808; color:#E8A050; }
body.dark .c-k    { background:#220A06; color:#E09070; }
body.dark .c-be   { background:#061A14; color:#50D0A0; }
body.dark .c-mg   { background:#180C30; color:#B090F0; }
body.dark .c-ca   { background:#081828; color:#70B0E0; }
body.dark .c-s1   { background:#0E2210; color:#70C050; }
body.dark .c-s2b  { background:#2A1808; color:#E8A050; }

/* ── KEYBOARD SHORTCUT HINT ── */
.kb-hint {
  display: none;
  text-align: center;
  font-size: 10px;
  color: var(--text3);
  margin-bottom: 0.5rem;
  letter-spacing: 0.04em;
}
@media (pointer: fine) {
  .kb-hint { display: block; }
}

/* ── RAPID MODE TOGGLE ── */
.rapid-toggle-wrap {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-bottom: 0.75rem;
}
.rapid-label {
  font-size: 11px;
  font-weight: 600;
  color: var(--text3);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.rapid-toggle {
  position: relative;
  width: 36px;
  height: 20px;
  cursor: pointer;
}
.rapid-toggle input {
  opacity: 0;
  width: 0;
  height: 0;
  position: absolute;
}
.rapid-slider {
  position: absolute;
  inset: 0;
  background: var(--prog-bg);
  border-radius: 99px;
  transition: background 0.2s;
}
.rapid-slider::before {
  content: '';
  position: absolute;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: #fff;
  top: 3px;
  left: 3px;
  transition: transform 0.2s;
  box-shadow: 0 1px 3px rgba(0,0,0,.2);
}
.rapid-toggle input:checked + .rapid-slider { background: var(--accent); }
.rapid-toggle input:checked + .rapid-slider::before { transform: translateX(16px); }

/* ── RAPID MODE CARD HIGHLIGHT ── */
body.rapid-mode .card-wrap { cursor: default; }
body.rapid-mode .face-hint { display: none; }

/* ── RESPONSIVE ── */
@media (max-width: 480px) {
  .face-main { font-size: 14px; }
  .btn { font-size: 14px; padding: 12px 16px; }
}