/* Study Lock web — "ink & highlighter", matching ios/StudyLock/DesignSystem/Ink.swift.
   Charcoal ink and ruled paper, one softened marker used only as a fill behind ink text.
   Apple-bundled faces first (as in the app), Google Fonts as fallback elsewhere. */

:root {
  --paper: #E6E8E1;
  --sheet: #F1F2EC;
  --ink: #1E201C;
  --text: #1E201C;
  --text-2: #4C5047;
  --accent: #4A5A14;
  --marker: #D3DE80;
  --rule: #2E312B;
  --rule-soft: rgba(46, 49, 43, 0.14);
  --signal: #C8573A;
  --band: #1E201C;
  --band-text: #DDE0D6;
  --band-text-2: #A7AC9E;
  --band-rule: #40443B;
  --plate-filter: none;

  --font-num: "DIN Condensed", "Barlow Condensed", sans-serif;
  --font-title: "Avenir Next Condensed", "Barlow Condensed", sans-serif;
  --font-body: "Avenir Next", "Barlow", sans-serif;
  --font-mono: Menlo, "IBM Plex Mono", ui-monospace, monospace;

  --gutter: clamp(16px, 4vw, 40px);
  --max: 1120px;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #171915;
    --sheet: #20231E;
    --text: #DDE0D6;
    --text-2: #A7AC9E;
    --accent: #B4C26C;
    --marker: #B4C26C;
    --rule: #40443B;
    --rule-soft: rgba(221, 224, 214, 0.08);
    --signal: #D97556;
    --band: #0F110E;
    --band-rule: #343830;
    --plate-filter: brightness(0.86) contrast(1.02);
  }
}

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

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background-color: var(--paper);
  /* Faint ruled-paper lines. */
  background-image: repeating-linear-gradient(to bottom, transparent 0 31px, var(--rule-soft) 31px 32px);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }

.skip {
  position: absolute; left: 12px; top: -48px; z-index: 10;
  background: var(--marker); color: var(--ink); padding: 8px 12px;
  font-family: var(--font-mono); font-size: 13px; font-weight: 700; text-decoration: none;
  border: 2px solid var(--ink);
}
.skip:focus { top: 12px; }

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

.wrap { max-width: var(--max); margin: 0 auto; padding: 0 var(--gutter); }

/* Typewriter eyebrow label. */
.stamp {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-2);
  margin: 0;
}

/* Highlighter stroke behind ink text. */
.hl {
  background: linear-gradient(176deg, transparent 22%, var(--marker) 22%, var(--marker) 86%, transparent 86%);
  -webkit-box-decoration-break: clone;
  box-decoration-break: clone;
  padding: 0 0.12em;
  margin: 0 -0.06em;
  color: var(--ink);
}

h1, h2, h3 {
  font-family: var(--font-title);
  font-weight: 800;
  line-height: 1.02;
  letter-spacing: -0.005em;
  margin: 0;
  text-wrap: balance;
}

/* ---------- Header ---------- */

.site-header { border-bottom: 2px solid var(--rule); background: var(--paper); }
.site-header .wrap {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  min-height: 64px;
}
.brand {
  display: inline-flex; align-items: center; gap: 10px;
  text-decoration: none;
  font-family: var(--font-title); font-weight: 800; font-size: 22px; letter-spacing: 0.02em;
  text-transform: uppercase;
}
.brand-mark {
  width: 34px; height: 34px; background: var(--ink); display: grid; place-items: center;
}
.brand-mark img { width: 30px; height: 30px; }
.site-nav { display: flex; align-items: center; gap: 22px; }
.site-nav a:not(.btn) {
  font-family: var(--font-mono); font-size: 12px; font-weight: 700; letter-spacing: 0.12em;
  text-transform: uppercase; text-decoration: none; color: var(--text-2);
}
.site-nav a:not(.btn):hover { color: var(--text); text-decoration: underline; text-underline-offset: 4px; }
@media (max-width: 760px) { .site-nav a:not(.btn) { display: none; } }

/* ---------- Stamp buttons ---------- */

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 10px;
  min-height: 48px; padding: 0 22px;
  font-family: var(--font-mono); font-size: 13px; font-weight: 700; letter-spacing: 0.12em;
  text-transform: uppercase; text-decoration: none;
  color: var(--ink); background: var(--marker);
  border: 2px solid var(--ink);
  box-shadow: 4px 4px 0 var(--rule);
  transition: transform 80ms ease, box-shadow 80ms ease;
}
.btn:hover { transform: translate(-1px, -1px); box-shadow: 5px 5px 0 var(--rule); }
.btn:active { transform: translate(4px, 4px); box-shadow: 0 0 0 var(--rule); }
.btn-small { min-height: 40px; padding: 0 14px; font-size: 12px; box-shadow: 3px 3px 0 var(--rule); }
.btn-ghost { background: transparent; color: var(--text); border-color: var(--text); box-shadow: none; }
.btn-ghost:hover { transform: none; box-shadow: none; background: var(--rule-soft); }
.btn-ghost:active { transform: none; }
@media (prefers-color-scheme: dark) {
  .btn { border-color: #0F110E; box-shadow: 4px 4px 0 #0A0B09; }
  .btn:hover { box-shadow: 5px 5px 0 #0A0B09; }
  .btn-small { box-shadow: 3px 3px 0 #0A0B09; }
  .btn-ghost { border-color: var(--text); box-shadow: none; }
  .btn-ghost:hover { box-shadow: none; }
}
@media (prefers-reduced-motion: reduce) { .btn { transition: none; } }

/* ---------- Hero ---------- */

.hero { padding: clamp(40px, 7vw, 88px) 0 clamp(48px, 7vw, 96px); border-bottom: 2px solid var(--rule); }
.hero .wrap {
  display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, 0.9fr);
  gap: clamp(32px, 5vw, 72px); align-items: center;
}
.hero h1 { font-size: clamp(48px, 8.4vw, 104px); text-transform: uppercase; margin: 18px 0 22px; }
.hero .lede { font-size: clamp(18px, 1.8vw, 20px); color: var(--text-2); max-width: 36ch; margin: 0 0 32px; }
.hero .lede strong { color: var(--text); font-weight: 600; }
.actions { display: flex; flex-wrap: wrap; gap: 14px 18px; align-items: center; }
.hero .note { margin-top: 22px; }

/* Session ticket: a printed mock of the in-app timer. */
.ticket {
  position: relative;
  background: var(--sheet);
  border: 2px solid var(--rule);
  box-shadow: 8px 8px 0 var(--rule);
  padding: 0;
}
@media (prefers-color-scheme: dark) { .ticket { box-shadow: 8px 8px 0 #0A0B09; } }
.ticket-plate { border-bottom: 2px solid var(--rule); background: #E6E8E1; }
.ticket-plate img { filter: var(--plate-filter); }
.ticket-body { padding: 20px 22px 24px; }
.ticket-row { display: flex; justify-content: space-between; align-items: baseline; gap: 12px; }
.clock {
  font-family: var(--font-num); font-weight: 700;
  font-size: clamp(72px, 9vw, 112px); line-height: 0.9; letter-spacing: 0.01em;
  font-variant-numeric: tabular-nums;
  margin: 10px 0 14px;
}
.bar { height: 16px; border: 2px solid var(--rule); background: transparent; position: relative; }
.bar span {
  position: absolute; inset: 0 auto 0 0; width: 38%; background: var(--marker);
  clip-path: polygon(0 0, 100% 6%, 97% 100%, 0 100%);
}
.ticket-foot { margin-top: 14px; font-size: 15px; color: var(--text-2); }

@media (max-width: 860px) {
  .hero .wrap { grid-template-columns: 1fr; }
  .ticket { max-width: 520px; }
}

/* ---------- Facts strip ---------- */

.facts { border-bottom: 2px solid var(--rule); background: var(--sheet); }
.facts ul {
  list-style: none; margin: 0 auto; padding: 0;
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr));
}
.facts li { padding: 26px var(--gutter) 24px; border-left: 1px solid var(--rule); }
.facts li:first-child { border-left: 0; }
.facts .num {
  font-family: var(--font-num); font-weight: 700; font-size: clamp(40px, 5vw, 56px); line-height: 1;
  display: block; margin-bottom: 6px;
}
.facts .num small { font-size: 0.45em; letter-spacing: 0.04em; margin-left: 4px; }
@media (max-width: 760px) {
  .facts ul { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .facts li:nth-child(3) { border-left: 0; }
  .facts li:nth-child(n+3) { border-top: 1px solid var(--rule); }
}

/* ---------- Ledger (features) ---------- */

.section { padding: clamp(56px, 8vw, 104px) 0; }
.section-head { display: grid; gap: 14px; margin-bottom: clamp(32px, 5vw, 56px); max-width: 720px; }
.section-head h2 { font-size: clamp(38px, 5.6vw, 64px); text-transform: uppercase; }
.section-head p:not(.stamp) { margin: 0; color: var(--text-2); font-size: 18px; }

.ledger { list-style: none; margin: 0; padding: 0; border-top: 2px solid var(--rule); }
.entry {
  display: grid;
  grid-template-columns: 96px minmax(0, 1fr) minmax(0, 0.8fr);
  gap: clamp(20px, 4vw, 48px);
  padding: clamp(28px, 4vw, 44px) 0;
  border-bottom: 1px solid var(--rule);
  align-items: start;
}
.entry-no {
  font-family: var(--font-num); font-weight: 700; font-size: 72px; line-height: 0.8;
  color: var(--text); letter-spacing: 0.01em;
}
.entry h3 { font-size: clamp(28px, 3.4vw, 40px); text-transform: uppercase; margin: 8px 0 14px; }
.entry ul { margin: 0; padding: 0; list-style: none; display: grid; gap: 10px; }
.entry li { padding-left: 26px; position: relative; color: var(--text-2); }
.entry li strong { color: var(--text); font-weight: 600; }
.entry li::before {
  content: ""; position: absolute; left: 0; top: 0.62em; width: 14px; height: 8px;
  background: var(--marker); transform: skewX(-14deg);
}
.plate { border: 2px solid var(--rule); background: #E6E8E1; }
.plate img { filter: var(--plate-filter); aspect-ratio: 3 / 2; object-fit: cover; width: 100%; }
@media (max-width: 860px) {
  .entry { grid-template-columns: 64px minmax(0, 1fr); }
  .entry-no { font-size: 56px; }
  .entry .plate { grid-column: 2; max-width: 440px; }
}
@media (max-width: 480px) {
  .entry { grid-template-columns: 1fr; gap: 14px; }
  .entry .plate { grid-column: 1; }
}

/* ---------- Privacy band (ink) ---------- */

.band { background: var(--band); color: var(--band-text); border-top: 2px solid var(--rule); border-bottom: 2px solid var(--rule); }
.band .wrap {
  display: grid; grid-template-columns: minmax(0, 0.8fr) minmax(0, 1.2fr);
  gap: clamp(32px, 6vw, 80px); align-items: center;
}
.band .stamp { color: var(--band-text-2); }
.band h2 { font-size: clamp(38px, 5.6vw, 64px); text-transform: uppercase; margin: 14px 0 0; }
.band .hl { color: #1E201C; }
.band-mark { width: min(300px, 70%); margin: 0 auto; }
.checks { list-style: none; margin: 28px 0 0; padding: 0; display: grid; gap: 0; }
.checks li {
  display: grid; grid-template-columns: 40px minmax(0, 1fr); gap: 14px;
  padding: 16px 0; border-top: 1px solid var(--band-rule); color: var(--band-text-2);
}
.checks li:last-child { border-bottom: 1px solid var(--band-rule); }
.checks strong { color: var(--band-text); font-weight: 600; display: block; }
.tick {
  width: 28px; height: 28px; border: 2px solid var(--band-text); display: grid; place-items: center;
  font-family: var(--font-mono); font-weight: 700; font-size: 14px; color: var(--band-text);
}
.band a { color: var(--band-text); text-underline-offset: 4px; }
@media (max-width: 860px) {
  .band .wrap { grid-template-columns: 1fr; }
  .band-mark { width: 180px; margin: 0; }
}

/* ---------- Pricing ---------- */

.plans { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: clamp(20px, 3vw, 36px); max-width: 880px; }
.plan {
  background: var(--sheet); border: 2px solid var(--rule); padding: 26px 26px 28px;
  display: flex; flex-direction: column; gap: 6px; position: relative;
}
.plan-featured { box-shadow: 8px 8px 0 var(--rule); }
@media (prefers-color-scheme: dark) { .plan-featured { box-shadow: 8px 8px 0 #0A0B09; } }
.plan h3 { font-size: 30px; text-transform: uppercase; }
.price { font-family: var(--font-num); font-weight: 700; font-size: clamp(64px, 8vw, 84px); line-height: 0.95; margin: 14px 0 0; }
.price small { font-family: var(--font-mono); font-size: 14px; font-weight: 700; letter-spacing: 0.08em; margin-left: 6px; color: var(--text-2); }
.plan .detail { margin: 6px 0 0; color: var(--text-2); }
.plan .trial { align-self: flex-start; margin-top: 2px; }
.flag {
  position: absolute; top: -14px; right: 18px;
  background: var(--marker); color: var(--ink); border: 2px solid var(--ink);
  font-family: var(--font-mono); font-size: 11px; font-weight: 700; letter-spacing: 0.14em; text-transform: uppercase;
  padding: 4px 8px; transform: rotate(2deg);
}
.fine { margin-top: 32px; max-width: 760px; font-size: 14px; color: var(--text-2); }
.fine p { margin: 0 0 10px; }
@media (max-width: 680px) { .plans { grid-template-columns: 1fr; } }

/* ---------- Closing CTA ---------- */

.closing { border-top: 2px solid var(--rule); }
.closing .wrap {
  display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 0.7fr); gap: clamp(28px, 5vw, 64px); align-items: center;
}
.closing h2 { font-size: clamp(40px, 6vw, 72px); text-transform: uppercase; margin: 14px 0 26px; }
@media (max-width: 760px) { .closing .wrap { grid-template-columns: 1fr; } .closing .plate { max-width: 440px; } }

/* ---------- Footer ---------- */

.site-footer { border-top: 2px solid var(--rule); padding: 28px 0 40px; font-size: 14px; color: var(--text-2); }
.site-footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 16px 32px; align-items: center; }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 8px 24px; }
.site-footer a { font-family: var(--font-mono); font-size: 12px; font-weight: 700; letter-spacing: 0.12em; text-transform: uppercase; text-underline-offset: 4px; }

/* ---------- Legal page ---------- */

.legal { padding: clamp(40px, 6vw, 80px) 0 clamp(56px, 8vw, 104px); }
.legal .wrap { max-width: 760px; }
.legal h1 { font-size: clamp(44px, 7vw, 80px); text-transform: uppercase; margin: 14px 0 16px; }
.legal .meta { margin: 0 0 28px; padding-bottom: 24px; border-bottom: 2px solid var(--rule); }
.legal .summary {
  font-size: 19px; margin: 0 0 8px; padding: 18px 20px; background: var(--sheet); border: 2px solid var(--rule);
}
.legal h2 {
  font-size: clamp(26px, 3.2vw, 32px); text-transform: uppercase;
  margin: 44px 0 12px; padding-top: 14px; border-top: 1px solid var(--rule);
}
.legal p, .legal li { color: var(--text); }
.legal ul { padding-left: 0; list-style: none; display: grid; gap: 10px; }
.legal li { padding-left: 26px; position: relative; }
.legal li::before {
  content: ""; position: absolute; left: 0; top: 0.62em; width: 14px; height: 8px;
  background: var(--marker); transform: skewX(-14deg);
}
.legal address { font-style: normal; }
/* Unfilled placeholders from the draft, left visible on purpose. */
.todo {
  font-family: var(--font-mono); font-size: 0.88em;
  border: 1px dashed var(--signal); color: var(--signal); padding: 0 4px;
}