/* ==========================================================================
   PrepMora — base layer
   Tokens, reset, typography, and the primitives shared by every page.
   ========================================================================== */

/* --- Theme tokens ------------------------------------------------------- */

:root {
  color-scheme: dark;

  /* Surfaces: near-black with a green cast so turquoise belongs to the family */
  --bg: #060f0e;
  --bg-deep: #030908;
  --surface: #0c1a18;
  --surface-2: #112320;
  --surface-3: #17302c;
  --line: #1b322d;
  --line-soft: #132522;

  /* Ink */
  --text: #e4f1ee;
  --text-2: #a3bdb7;
  --text-3: #6b8983;

  /* Accent */
  --accent: #2fe3c6;
  --accent-2: #12a88f;
  --accent-ink: #04211c;
  --accent-wash: rgba(47, 227, 198, 0.12);
  --accent-line: rgba(47, 227, 198, 0.28);

  /* Domain identity — one hue per SAT domain, used as a card spine */
  --d-1: #4c8dff;
  --d-2: #a97bff;
  --d-3: #ff9f5a;
  --d-4: #2fe3c6;

  /* Status */
  --good: #3fd68c;
  --warn: #ffb454;
  --bad: #ff6f6f;
  --good-wash: rgba(63, 214, 140, 0.13);
  --warn-wash: rgba(255, 180, 84, 0.13);
  --bad-wash: rgba(255, 111, 111, 0.13);

  --shadow-1: 0 1px 2px rgba(0, 0, 0, 0.4);
  --shadow-2: 0 18px 40px -24px rgba(0, 0, 0, 0.9);
  --shadow-3: 0 28px 70px -30px rgba(0, 0, 0, 0.95);

  /* Type */
  --font-display: "Bricolage Grotesque", "Segoe UI", system-ui, sans-serif;
  --font-body: "Public Sans", "Segoe UI", system-ui, -apple-system, sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, "Cascadia Mono", Consolas, monospace;

  /* Question typography — deliberately fixed at 16px */
  --q-size: 16px;
  --q-leading: 1.75;
  --q-measure: 68ch;

  /* Space (4px base) */
  --s1: 4px;
  --s2: 8px;
  --s3: 12px;
  --s4: 16px;
  --s5: 20px;
  --s6: 24px;
  --s7: 32px;
  --s8: 40px;
  --s9: 56px;
  --s10: 72px;
  --s11: 96px;

  /* Radius */
  --r1: 8px;
  --r2: 12px;
  --r3: 16px;
  --r4: 22px;
  --rp: 999px;

  --sidebar-w: 264px;
  --page-max: 1180px;
}

[data-theme="light"] {
  color-scheme: light;

  --bg: #f1f6f5;
  --bg-deep: #e6eeec;
  --surface: #ffffff;
  --surface-2: #f4f8f7;
  --surface-3: #e9f1ef;
  --line: #dce8e5;
  --line-soft: #e9f0ee;

  --text: #08201c;
  --text-2: #456058;
  --text-3: #6d8781;

  --accent: #0b8f79;
  --accent-2: #067a66;
  --accent-ink: #ffffff;
  --accent-wash: rgba(11, 143, 121, 0.09);
  --accent-line: rgba(11, 143, 121, 0.24);

  --d-1: #2f6fe0;
  --d-2: #7d4fdb;
  --d-3: #d97a2b;
  --d-4: #0b9d85;

  --good: #12915d;
  --warn: #b87316;
  --bad: #cf3f3f;
  --good-wash: rgba(18, 145, 93, 0.1);
  --warn-wash: rgba(184, 115, 22, 0.1);
  --bad-wash: rgba(207, 63, 63, 0.1);

  --shadow-1: 0 1px 2px rgba(12, 40, 34, 0.06);
  --shadow-2: 0 16px 34px -22px rgba(12, 40, 34, 0.34);
  --shadow-3: 0 26px 60px -28px rgba(12, 40, 34, 0.4);
}

/* --- Reset -------------------------------------------------------------- */

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

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
  font-weight: 400;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img,
svg {
  display: block;
  max-width: 100%;
}

/* Component classes set `display`, which would otherwise beat the UA rule for
   [hidden]. Everything toggled from JS relies on this winning. */
[hidden] {
  display: none !important;
}

/* Two fractions on consecutive lines (\dfrac, <br>, \dfrac) touched: the upper
   denominator ran into the lower numerator, because a line box ends exactly at
   a tall inline formula's edge (Practice Test #3 math1:21, 2026-09-26). An
   inline-block's margin box counts toward its line box, so a formula carrying a
   fraction or an array gets air above and below it. Display math keeps KaTeX's
   own block margins. Same rule in bluebook.css and exam.css. */
:not(.katex-display) > .katex:has(.mfrac, .mtable) {
  display: inline-block;
  margin: 0.25em 0;
}

button,
input,
select,
textarea {
  font: inherit;
  color: inherit;
}

button {
  background: none;
  border: 0;
  cursor: pointer;
}

a {
  color: inherit;
  text-decoration: none;
}

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

h1,
h2,
h3,
h4,
p {
  margin: 0;
}

table {
  border-collapse: collapse;
  width: 100%;
}

hr {
  border: 0;
  border-top: 1px solid var(--line);
  margin: var(--s6) 0;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

::selection {
  background: var(--accent);
  color: var(--accent-ink);
}

/* --- Typography --------------------------------------------------------- */

.display-xl,
.display,
.h1,
.h2,
.h3 {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.028em;
  line-height: 1.04;
}

.display-xl {
  font-size: clamp(2.6rem, 6.2vw, 4.6rem);
  line-height: 0.98;
  letter-spacing: -0.038em;
}

.display {
  font-size: clamp(1.9rem, 3.6vw, 2.85rem);
  letter-spacing: -0.032em;
}

.h1 {
  font-size: 1.75rem;
  font-weight: 600;
}

.h2 {
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: -0.02em;
}

.h3 {
  font-size: 1.0625rem;
  font-weight: 600;
  letter-spacing: -0.012em;
  line-height: 1.35;
}

.eyebrow {
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.19em;
  text-transform: uppercase;
  color: var(--text-3);
  line-height: 1.4;
}

.eyebrow-accent {
  color: var(--accent);
}

.lede {
  font-size: 1.0625rem;
  line-height: 1.7;
  color: var(--text-2);
}

.muted {
  color: var(--text-2);
}

.dim {
  color: var(--text-3);
}

.small {
  font-size: 0.875rem;
  line-height: 1.55;
}

.tiny {
  font-size: 0.8125rem;
  line-height: 1.5;
}

.mono {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.01em;
}

.num {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-weight: 500;
}

.accent-text {
  color: var(--accent);
}

/* --- Buttons ------------------------------------------------------------ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--s2);
  padding: 11px 18px;
  border-radius: var(--rp);
  border: 1px solid transparent;
  font-size: 0.9375rem;
  font-weight: 600;
  letter-spacing: -0.008em;
  white-space: nowrap;
  transition: background-color 0.16s ease, border-color 0.16s ease,
    color 0.16s ease, transform 0.16s ease, box-shadow 0.16s ease;
}

.btn:active {
  transform: translateY(1px);
}

.btn-primary {
  background: var(--accent);
  color: var(--accent-ink);
  box-shadow: 0 0 0 1px var(--accent-line), 0 10px 26px -14px var(--accent);
}

.btn-primary:hover {
  background: color-mix(in oklab, var(--accent) 88%, #ffffff);
}

.btn-ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--text);
}

.btn-ghost:hover {
  border-color: var(--accent-line);
  background: var(--accent-wash);
  color: var(--accent);
}

.btn-quiet {
  background: var(--surface-2);
  border-color: var(--line);
  color: var(--text-2);
}

.btn-quiet:hover {
  color: var(--text);
  border-color: var(--text-3);
}

.btn-sm {
  padding: 7px 13px;
  font-size: 0.8125rem;
}

.btn-lg {
  padding: 14px 26px;
  font-size: 1rem;
}

.btn-block {
  width: 100%;
}

.btn[disabled],
.btn[aria-disabled="true"] {
  opacity: 0.45;
  pointer-events: none;
}

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  color: var(--accent);
  font-size: 0.8125rem;
  font-weight: 600;
}

.link-arrow svg {
  transition: transform 0.16s ease;
}

.link-arrow:hover svg {
  transform: translateX(3px);
}

/* --- Surfaces ----------------------------------------------------------- */

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r3);
  box-shadow: var(--shadow-1);
}

.card-pad {
  padding: var(--s6);
}

.card-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--s5);
  margin-bottom: var(--s5);
}

/* Domain spine — a 3px rule that encodes which SAT domain a card belongs to */
.spine {
  position: relative;
  overflow: hidden;
}

.spine::before {
  content: "";
  position: absolute;
  inset: 14px auto 14px 0;
  width: 3px;
  border-radius: var(--rp);
  background: var(--spine, var(--accent));
}

.spine-1 {
  --spine: var(--d-1);
}
.spine-2 {
  --spine: var(--d-2);
}
.spine-3 {
  --spine: var(--d-3);
}
.spine-4 {
  --spine: var(--d-4);
}

/* --- Chips, tags, badges ------------------------------------------------ */

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 11px;
  border-radius: var(--rp);
  border: 1px solid var(--line);
  background: var(--surface-2);
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-2);
  letter-spacing: 0.01em;
}

.chip-accent {
  border-color: var(--accent-line);
  background: var(--accent-wash);
  color: var(--accent);
}

.chip-good {
  border-color: transparent;
  background: var(--good-wash);
  color: var(--good);
}

.chip-warn {
  border-color: transparent;
  background: var(--warn-wash);
  color: var(--warn);
}

.chip-bad {
  border-color: transparent;
  background: var(--bad-wash);
  color: var(--bad);
}

.dot {
  width: 7px;
  height: 7px;
  border-radius: var(--rp);
  background: currentColor;
  flex: none;
}

/* --- Forms -------------------------------------------------------------- */

.field {
  display: block;
  margin-bottom: var(--s5);
}

.field-label {
  display: block;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-2);
  margin-bottom: 7px;
}

.input,
.select,
.textarea {
  width: 100%;
  padding: 12px 14px;
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: var(--r2);
  font-size: 0.9375rem;
  transition: border-color 0.15s ease, background-color 0.15s ease;
}

.input::placeholder,
.textarea::placeholder {
  color: var(--text-3);
}

.input:focus,
.select:focus,
.textarea:focus {
  outline: none;
  border-color: var(--accent);
  background: var(--surface);
}

.select {
  appearance: none;
  padding-right: 34px;
  background-image: linear-gradient(45deg, transparent 50%, currentColor 50%),
    linear-gradient(135deg, currentColor 50%, transparent 50%);
  background-position: calc(100% - 17px) 55%, calc(100% - 12px) 55%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
  cursor: pointer;
}

.field-hint {
  font-size: 0.8125rem;
  color: var(--text-3);
  margin-top: 6px;
}

.field-input-wrap {
  position: relative;
}

.field-input-wrap .input {
  padding-right: 44px;
}

.eye-btn {
  position: absolute;
  top: 50%;
  right: 6px;
  transform: translateY(-50%);
  display: grid;
  place-items: center;
  width: 32px;
  height: 32px;
  border-radius: var(--r2);
  color: var(--text-3);
  transition: color 0.15s ease;
}

.eye-btn:hover {
  color: var(--accent);
}

/* --- Segmented control -------------------------------------------------- */

.segment {
  display: inline-flex;
  padding: 4px;
  gap: 2px;
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: var(--rp);
}

.segment button {
  padding: 7px 16px;
  border-radius: var(--rp);
  font-size: 0.8438rem;
  font-weight: 600;
  color: var(--text-3);
  transition: background-color 0.16s ease, color 0.16s ease;
}

.segment button:hover {
  color: var(--text);
}

.segment button[aria-selected="true"] {
  background: var(--accent);
  color: var(--accent-ink);
}

/* --- The signature: 400–1600 score rail --------------------------------- */

.rail {
  --rail-pct: 50%;
  --rail-target: 75%;
  display: block;
  width: 100%;
}

.rail-track {
  position: relative;
  height: 8px;
  border-radius: var(--rp);
  background: var(--surface-3);
  overflow: visible;
}

.rail-fill {
  position: absolute;
  inset: 0 auto 0 0;
  width: var(--rail-pct);
  border-radius: var(--rp);
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  transition: width 1.1s cubic-bezier(0.22, 1, 0.36, 1);
}

.rail-target {
  position: absolute;
  top: -6px;
  bottom: -6px;
  left: var(--rail-target);
  width: 2px;
  background: var(--text-3);
  border-radius: var(--rp);
}

.rail-marker {
  position: absolute;
  top: 50%;
  left: var(--rail-pct);
  width: 16px;
  height: 16px;
  margin: -8px 0 0 -8px;
  border-radius: var(--rp);
  background: var(--accent);
  border: 3px solid var(--bg);
  box-shadow: 0 0 0 1px var(--accent), 0 0 22px -2px var(--accent);
  transition: left 1.1s cubic-bezier(0.22, 1, 0.36, 1);
}

.rail-ticks {
  display: flex;
  justify-content: space-between;
  margin-top: var(--s3);
  font-family: var(--font-mono);
  font-size: 0.6875rem;
  color: var(--text-3);
  letter-spacing: 0.02em;
}

/* --- Progress bars ------------------------------------------------------ */

.bar {
  height: 6px;
  border-radius: var(--rp);
  background: var(--surface-3);
  overflow: hidden;
}

.bar-fill {
  height: 100%;
  border-radius: var(--rp);
  background: var(--accent);
  width: 0;
  transition: width 0.9s cubic-bezier(0.22, 1, 0.36, 1);
}

/* --- Tables ------------------------------------------------------------- */

.table-wrap {
  overflow-x: auto;
}

.table {
  min-width: 640px;
}

.table th {
  text-align: left;
  font-size: 0.6875rem;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--text-3);
  padding: 0 var(--s4) var(--s3);
  white-space: nowrap;
}

.table td {
  padding: var(--s4);
  border-top: 1px solid var(--line-soft);
  font-size: 0.9063rem;
  vertical-align: middle;
}

.table tbody tr {
  transition: background-color 0.14s ease;
}

.table tbody tr:hover {
  background: var(--surface-2);
}

.table .num-cell {
  font-family: var(--font-mono);
  font-variant-numeric: tabular-nums;
  font-size: 0.875rem;
}

/* --- Layout helpers ----------------------------------------------------- */

.stack > * + * {
  margin-top: var(--s5);
}

.stack-tight > * + * {
  margin-top: var(--s3);
}

.stack-loose > * + * {
  margin-top: var(--s7);
}

.row {
  display: flex;
  align-items: center;
  gap: var(--s3);
}

.row-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s4);
}

.wrap {
  flex-wrap: wrap;
}

.grow {
  flex: 1;
  min-width: 0;
}

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--s5);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: var(--s5);
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: var(--s4);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: var(--s4);
  top: -60px;
  z-index: 100;
  padding: 10px 16px;
  border-radius: var(--rp);
  background: var(--accent);
  color: var(--accent-ink);
  font-weight: 600;
  transition: top 0.16s ease;
}

.skip-link:focus {
  top: var(--s4);
}

/* --- Brand mark --------------------------------------------------------- */

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  flex: none;
  border-radius: 10px;
  background: linear-gradient(150deg, var(--accent), var(--accent-2));
  color: var(--accent-ink);
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.0625rem;
  letter-spacing: -0.04em;
  box-shadow: 0 8px 22px -12px var(--accent);
}

.brand-name {
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 700;
  letter-spacing: -0.035em;
}

.brand-name em {
  font-style: normal;
  color: var(--accent);
}

/* PrepMora's own logo: the seal + a vector wordmark (brand/build_logo.py
   writes both inline). A white-label company keeps .brand-mark above. */
.brand-seal {
  display: block;
  width: 34px;
  height: 34px;
  flex: none;
  color: var(--text);
}

.brand-seal svg,
.brand-word svg {
  display: block;
  width: 100%;
  height: 100%;
}

.brand-word {
  display: block;
  height: 25px;
  aspect-ratio: 146.88 / 38;
  color: var(--text);
}

/* --- Motion ------------------------------------------------------------- */

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

@media (max-width: 900px) {
  .grid-3,
  .grid-4 {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 620px) {
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: minmax(0, 1fr);
  }
}