/* ============================================================
   interview-challenger — public landing
   Same "Prep Desk" tokens as web/src/styles.css: cool paper,
   graphite ink, one highlighter accent. Light/dark via light-dark();
   [data-theme] on <html> overrides the OS preference.
   ============================================================ */

:root {
  color-scheme: light dark;
  font-family: 'Instrument Sans', system-ui, sans-serif;
  font-synthesis: none;
  text-rendering: optimizeLegibility;

  --paper: light-dark(#f2f4f5, #14171a);
  --paper-2: light-dark(#ffffff, #1b1f23);
  --ink: light-dark(#1c2124, #eceff1);
  --graphite: light-dark(#5b666c, #98a2a8);
  --graphite-2: light-dark(#7c868c, #7d878d);
  --hairline: light-dark(#d7dde0, #2a3036);
  --field-line: light-dark(#c9d1d5, #343c43);
  --marker: light-dark(#e4ef4a, #c8d63f);
  --marker-soft: light-dark(#f2f6c4, #232c17);
  --correction: light-dark(#c4453a, #f2695c);

  --display: 'Bricolage Grotesque', 'Instrument Sans', system-ui, sans-serif;
  --mono: 'IBM Plex Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --ease: cubic-bezier(0.32, 0.72, 0, 1);
  --r: 10px;
}
:root[data-theme='light'] { color-scheme: light; }
:root[data-theme='dark'] { color-scheme: dark; }

* { box-sizing: border-box; }
html { background: var(--paper); scroll-padding-top: 16px; }
@media (prefers-reduced-motion: no-preference) { html { scroll-behavior: smooth; } }
body {
  margin: 0;
  min-width: 320px;
  color: var(--ink);
  background: var(--paper);
  font-size: 16px;
  line-height: 1.6;
  overflow-x: clip;
  transition: background-color 0.55s var(--ease), color 0.55s var(--ease);
}
img { display: block; max-width: 100%; height: auto; }
h1, h2, h3, p, ul, ol, dl, dd, figure { margin: 0; }
button { font: inherit; color: inherit; }
a:focus-visible, button:focus-visible {
  outline: 2px solid var(--ink);
  outline-offset: 3px;
  border-radius: 4px;
}

.wrap { width: 100%; max-width: 1240px; margin: 0 auto; padding: 0 40px; }
section { padding-block: clamp(64px, 9vw, 120px); }

.skip {
  position: absolute; left: 16px; top: -64px; z-index: 10;
  padding: 10px 16px; border-radius: var(--r);
  background: var(--ink); color: var(--paper); font-weight: 600; text-decoration: none;
}
.skip:focus { top: 16px; }

/* ---- topbar ----------------------------------------------------------- */
.topbar { display: flex; align-items: center; justify-content: space-between; gap: 16px; min-height: 72px; }
.wordmark { display: inline-flex; align-items: center; gap: 11px; color: var(--ink); text-decoration: none; font-family: var(--display); font-size: 17px; font-weight: 600; letter-spacing: -0.02em; }
.wordmark img { border-radius: 8px; }
.wordmark-light { color: var(--graphite); font-weight: 400; }
.topbar-actions { display: flex; align-items: center; gap: 12px; }
.icon-btn { width: 38px; height: 38px; display: grid; place-items: center; border: 1px solid var(--hairline); border-radius: 8px; background: var(--paper-2); color: var(--ink); cursor: pointer; transition: border-color 0.45s var(--ease), transform 0.45s var(--ease); }
.icon-btn:hover { border-color: var(--ink); }
.icon-btn:active { transform: scale(0.95); }
.seg { display: inline-flex; gap: 2px; padding: 3px; border: 1px solid var(--hairline); border-radius: 9px; background: var(--paper-2); }
.seg button { min-height: 30px; min-width: 38px; padding: 0 10px; border: 0; border-radius: 6px; background: transparent; color: var(--graphite); font-family: var(--mono); font-size: 12px; cursor: pointer; transition: color 0.4s var(--ease), box-shadow 0.4s var(--ease); }
.seg button:hover { color: var(--ink); }
.seg button[aria-pressed='true'] { color: var(--ink); box-shadow: inset 0 -2px 0 var(--marker); }

/* ---- shared type ------------------------------------------------------ */
h1, h2, h3 { font-family: var(--display); letter-spacing: -0.025em; font-weight: 600; }
h2 { font-size: clamp(1.7rem, 3.2vw, 2.5rem); line-height: 1.12; text-wrap: balance; }
h3 { font-size: 1.15rem; line-height: 1.25; }
.sub { color: var(--graphite); font-size: 1.1rem; max-width: 46ch; }
.mk { text-decoration: underline; text-decoration-color: var(--marker); text-decoration-thickness: 0.14em; text-underline-offset: 0.1em; text-decoration-skip-ink: none; }

/* ---- buttons / links -------------------------------------------------- */
.btn {
  display: inline-flex; align-items: center; min-height: 52px; padding: 0 26px;
  border-radius: var(--r); background: var(--ink); color: var(--paper);
  font-weight: 600; text-decoration: none;
  box-shadow: inset 0 -4px 0 var(--marker);
  transition: transform 0.4s var(--ease);
}
.btn:hover { transform: translateY(-2px); }
.btn:active { transform: translateY(0); }
.textlink { color: var(--ink); font-weight: 500; text-underline-offset: 4px; text-decoration-color: var(--graphite); }
.textlink:hover { text-decoration-color: var(--ink); }

/* ---- images ----------------------------------------------------------- */
.shot { border: 1px solid var(--hairline); border-radius: calc(var(--r) + 4px); background: var(--paper-2); overflow: hidden; }
.shot img { width: 100%; }

/* ---- 1. hero ---------------------------------------------------------- */
.hero { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); align-items: center; gap: 56px; padding-block: clamp(32px, 6vw, 72px) clamp(64px, 9vw, 112px); }
.hero h1 { font-size: clamp(1.9rem, 3.4vw, 2.6rem); line-height: 1.1; letter-spacing: -0.03em; }
.hero h1 .line { display: block; }
.hero .lede { margin-top: 24px; max-width: 40ch; color: var(--graphite); font-size: 1.15rem; }
.hero-shot { max-width: 640px; justify-self: end; }
.actions { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 28px; margin-top: 36px; }

/* ---- 2. how it works -------------------------------------------------- */
.how { border-top: 1px solid var(--hairline); }
.how-head { display: grid; grid-template-columns: minmax(0, 7fr) minmax(0, 4fr); align-items: end; gap: 24px 56px; margin-bottom: 56px; }
.how-head .sub { max-width: 32ch; }
.steps { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 32px; padding: 0; list-style: none; }
.step { border-top: 1px solid var(--field-line); padding-top: 0; }
.step::before { content: ''; display: block; width: 36px; height: 4px; margin-top: -1px; background: var(--marker); }
.num { display: block; margin: 18px 0 14px; font-family: var(--mono); font-size: 13px; color: var(--graphite); }
.step h3 { margin-bottom: 10px; }
.step p { color: var(--graphite); font-size: 0.97rem; }

/* ---- 3. practice ------------------------------------------------------ */
.practice { background: var(--paper-2); border-block: 1px solid var(--hairline); }
.split { display: grid; grid-template-columns: minmax(0, 5fr) minmax(0, 7fr); align-items: center; gap: 64px; }
.split-text h2 { margin-bottom: 20px; }
.ticks { display: grid; margin-top: 32px; padding: 0; list-style: none; }
.ticks li { position: relative; padding: 16px 0 16px 30px; border-top: 1px solid var(--hairline); }
.ticks li:last-child { border-bottom: 1px solid var(--hairline); }
.ticks li::before { content: ''; position: absolute; left: 0; top: 1.5em; width: 16px; height: 6px; border-radius: 3px; background: var(--marker); }

/* ---- 4. themes (bento) ------------------------------------------------ */
.themes-head { display: grid; gap: 14px; max-width: 60ch; margin-bottom: 48px; }
.bento { display: grid; grid-template-columns: repeat(12, minmax(0, 1fr)); gap: 14px; padding: 0; list-style: none; }
.cell { position: relative; overflow: hidden; display: flex; flex-direction: column; justify-content: space-between; gap: 40px; min-height: 240px; padding: 26px; border-radius: calc(var(--r) + 6px); }
.cell p { margin: 0; }
.cell h3 { margin-bottom: 2px; }
.cell-foot p { font-size: 0.92rem; }
.c-python { grid-column: span 7; min-height: 300px; }
.c-editorial { grid-column: span 5; }
.c-studio, .c-devops, .c-aurora { grid-column: span 4; }
.note { margin-top: 24px; color: var(--graphite); font-size: 0.95rem; }

.c-python { background: radial-gradient(rgba(70, 224, 138, 0.2) 1px, transparent 1px) 0 0 / 16px 16px, #0c110e; color: #d7f5df; font-family: 'IBM Plex Mono', ui-monospace, monospace; }
.c-python .cell-foot p { color: #8fb09b; }
.c-python .sp-prompt { color: #46e08a; font-size: 0.85rem; }
.c-python .sp-title { margin: 10px 0 16px; font-size: 1.5rem; font-weight: 500; }
.c-python .sp-opts { display: flex; gap: 8px; }
.c-python .sp-opts span { padding: 4px 14px; border: 1px solid #2f4a39; border-radius: 6px; font-size: 0.85rem; }
.c-python .sp-opts .on { background: #46e08a; border-color: #46e08a; color: #0c110e; font-weight: 600; }

.c-editorial { background: #f5eddc; color: #2a1f14; font-family: Georgia, 'Times New Roman', serif; }
.c-editorial h3 { font-family: Georgia, 'Times New Roman', serif; font-weight: 700; letter-spacing: 0; }
.c-editorial .cell-foot p { color: #6b5a46; font-family: 'Instrument Sans', system-ui, sans-serif; }
.c-editorial .sp-kicker { font-size: 0.8rem; font-style: italic; color: #8a4a2c; }
.c-editorial .sp-title { margin: 6px 0 14px; font-size: 2rem; line-height: 1.1; font-style: italic; }
.c-editorial .sp-rule { width: 56px; height: 3px; background: #b4532a; }

.c-studio { background: linear-gradient(160deg, #243248, #1a2331); color: #e8eef7; box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.1); }
.c-studio .cell-foot p { color: #9fb0c6; }
.c-studio .sp-chip { display: inline-block; padding: 3px 12px; border-radius: 999px; background: rgba(77, 163, 255, 0.18); color: #9cccff; font-size: 0.8rem; font-weight: 500; }
.c-studio .sp-title { margin-top: 14px; font-size: 1.35rem; font-weight: 600; line-height: 1.2; }

.c-devops { background: linear-gradient(rgba(120, 160, 255, 0.15) 1px, transparent 1px) 0 0 / 24px 24px, linear-gradient(90deg, rgba(120, 160, 255, 0.15) 1px, transparent 1px) 0 0 / 24px 24px, #0a1b3a; color: #dce8ff; }
.c-devops .cell-foot p { color: #9db4de; }
.c-devops .sp-prompt { font-family: var(--mono); font-size: 0.8rem; color: #9cc0ff; }
.c-devops .sp-title { margin-top: 10px; font-size: 1.3rem; font-weight: 600; line-height: 1.2; }

.c-aurora { background: radial-gradient(60% 80% at 15% 100%, rgba(31, 181, 160, 0.5), transparent 62%), radial-gradient(50% 70% at 95% 0%, rgba(110, 86, 210, 0.4), transparent 62%), radial-gradient(40% 50% at 60% 60%, rgba(228, 239, 74, 0.1), transparent 70%), #050507; color: #f2f4f8; }
.c-aurora .cell-foot p { color: #dfe5ee; }
.c-aurora .sp-title { font-family: var(--display); font-size: 1.9rem; font-weight: 600; line-height: 1.05; letter-spacing: -0.03em; }

/* ---- 5. private site -------------------------------------------------- */
.split-rev { grid-template-columns: minmax(0, 5fr) minmax(0, 6fr); }
.offset { position: relative; max-width: 460px; }
.offset::before { content: ''; position: absolute; inset: 20px 20px -20px -20px; border-radius: calc(var(--r) + 4px); background: var(--marker-soft); border: 1px solid var(--hairline); }
.portrait { position: relative; }
.facts { display: grid; margin-top: 32px; }
.facts > div { padding: 18px 0; border-top: 1px solid var(--hairline); }
.facts > div:last-child { border-bottom: 1px solid var(--hairline); }
.facts dt { font-family: var(--display); font-size: 1.1rem; font-weight: 600; letter-spacing: -0.015em; }
.facts dd { margin-top: 4px; color: var(--graphite); }

/* ---- 6. final band + footer ------------------------------------------ */
.band { background: var(--marker); color: #1c2124; padding-block: clamp(56px, 8vw, 96px); }
.band a:focus-visible { outline-color: #1c2124; }
.band-in { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 28px 48px; }
.band h2 { max-width: 20ch; font-size: clamp(1.8rem, 3.6vw, 2.9rem); }
.band .btn { background: #1c2124; color: #f2f4f5; box-shadow: inset 0 -4px 0 #e4ef4a; }

.foot { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 16px 32px; padding-block: 32px 40px; }
.foot-brand { color: var(--graphite); font-size: 0.9rem; }
.foot-links { display: flex; gap: 24px; }
.foot-links a { color: var(--ink); text-underline-offset: 4px; }

/* ---- responsive ------------------------------------------------------- */
@media (max-width: 1000px) {
  .hero, .split, .split-rev { grid-template-columns: minmax(0, 1fr); gap: 48px; }
  .hero-shot { justify-self: start; }
  .how-head { grid-template-columns: minmax(0, 1fr); }
  .steps { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 40px 32px; }
  .c-python { grid-column: span 12; }
  .c-editorial, .c-studio, .c-devops { grid-column: span 6; }
  .c-aurora { grid-column: span 12; }
  .split-rev .offset { order: 2; }
}
@media (max-width: 620px) {
  .wrap { padding-inline: 20px; }
  .steps { grid-template-columns: minmax(0, 1fr); }
  .cell, .c-python, .c-editorial, .c-studio, .c-devops, .c-aurora { grid-column: span 12; min-height: 200px; }
  .offset::before { inset: 14px 14px -14px -14px; }
  .offset { margin-left: 14px; }
  .actions { gap: 16px 24px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; animation: none !important; }
  .btn:hover, .icon-btn:active { transform: none; }
}