/*
 * Landing page styles for AI検定 (株式会社ZETTAI).
 * Self-contained; no dependency on the eiken-derived stylesheet.
 * Palette mirrors the navy used in /ai-kentei/.
 */

:root {
  --navy: #1b3b8b;
  --navy-deep: #0e255a;
  --accent: #2f6fed;
  --tint: #eaf0fb;
  --ink: #0e1726;
  --ink-soft: #44546a;
  --line: #d9dee8;
  --bg: #ffffff;
  --bg-soft: #f4f6fa;
  --max: 1200px;
  --pad: clamp(20px, 4vw, 48px);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body.lp {
  margin: 0;
  font-family: -apple-system, "Hiragino Kaku Gothic ProN", "Hiragino Sans",
    "Noto Sans JP", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.75;
  font-feature-settings: "palt";
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }

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

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

.lp-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.lp-header__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 14px var(--pad);
  display: flex;
  align-items: center;
  gap: 24px;
}

.lp-logo {
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
}

.lp-logo svg { height: 44px; width: auto; display: block; }

.lp-nav {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
}

.lp-nav__link {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  text-decoration: none;
  color: var(--ink);
  padding: 6px 12px;
  border-radius: 6px;
  transition: background 0.15s ease, color 0.15s ease;
  line-height: 1.2;
}

.lp-nav__link:hover {
  background: var(--tint);
  color: var(--navy);
}

.lp-nav__en {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.lp-nav__jp {
  font-size: 10px;
  color: var(--ink-soft);
  margin-top: 2px;
}

.lp-header__cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 22px;
  border: 1.5px solid var(--ink);
  text-decoration: none;
  font-weight: 700;
  font-size: 14px;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
  white-space: nowrap;
}

.lp-header__cta:hover {
  background: var(--navy);
  color: #fff;
  border-color: var(--navy);
}

@media (max-width: 900px) {
  .lp-nav { display: none; }
}

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

.lp-hero { position: relative; }

/*
 * Hero photo is a wide brand banner (3840x900 ≈ 4.27:1) with
 * "AI検定 / 株式会社ZETTAI" centered in the frame. The visible aspect is
 * pulled in slightly to 7:2 (3.5:1) so the photo has more vertical
 * presence on desktop; that crops ~150px off each side at 1440vw, which
 * is well outside the centered lettering and the central composition, so
 * nothing essential is lost and the sides do not feel awkwardly chopped.
 *
 * Below ~720px the wide ratio becomes an unreadably thin strip, so we
 * swap to a near-square aspect via media query.
 */
.lp-hero__media {
  position: relative;
  width: 100%;
  aspect-ratio: 7 / 2;
  overflow: hidden;
  background: #eef3fb;
}

.lp-hero__media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

.lp-hero__tint {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(255, 255, 255, 0) 0%,
    rgba(255, 255, 255, 0) 60%,
    rgba(14, 37, 90, 0.12) 100%
  );
  pointer-events: none;
}

@media (max-width: 720px) {
  .lp-hero__media { aspect-ratio: 750 / 760; }
}

.lp-hero__band {
  background: var(--navy);
  color: #fff;
  position: relative;
}

.lp-hero__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 56px var(--pad) 72px;
}

.lp-hero__en {
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 800;
  letter-spacing: 0.15em;
  margin: 0 0 8px;
  color: #fff;
}

.lp-hero__title {
  font-size: clamp(28px, 4.5vw, 48px);
  line-height: 1.35;
  margin: 0 0 20px;
  font-weight: 800;
}

.lp-hero__lead {
  font-size: clamp(15px, 1.6vw, 18px);
  margin: 0 0 28px;
  max-width: 720px;
  color: rgba(255, 255, 255, 0.92);
}

.lp-hero__ctas {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

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

.lp-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 32px;
  text-decoration: none;
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.04em;
  transition: transform 0.1s ease, background 0.15s ease, color 0.15s ease;
}

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

.lp-btn--primary {
  background: #fff;
  color: var(--navy);
}

.lp-btn--primary:hover { background: var(--tint); }

.lp-btn--ghost {
  background: transparent;
  color: #fff;
  border: 1.5px solid #fff;
}

.lp-btn--ghost:hover {
  background: #fff;
  color: var(--navy);
}

/* ------- Sections ------- */

.lp-section {
  max-width: var(--max);
  margin: 0 auto;
  padding: 88px var(--pad);
}

.lp-section__head { margin-bottom: 48px; }

.lp-h2 {
  display: flex;
  align-items: baseline;
  gap: 16px;
  flex-wrap: wrap;
  margin: 0;
  font-size: clamp(22px, 2.6vw, 30px);
  font-weight: 800;
  color: var(--navy-deep);
}

.lp-h2__en {
  font-size: clamp(28px, 4vw, 42px);
  letter-spacing: 0.15em;
  color: var(--navy-deep);
}

.lp-h2__sep { color: var(--line); font-weight: 400; }

.lp-h2__jp { font-size: clamp(16px, 1.8vw, 22px); color: var(--ink-soft); }

.lp-section__lead {
  margin: 12px 0 0;
  color: var(--ink-soft);
  font-size: 15px;
}

/* ------- About ------- */

.lp-about { background: var(--bg-soft); max-width: none; }
.lp-about > .lp-section__head,
.lp-about > .lp-about__grid {
  max-width: var(--max);
  margin-left: auto;
  margin-right: auto;
}

.lp-about__grid {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 32px;
  align-items: start;
}

.lp-about__label {
  background: var(--accent);
  color: #fff;
  font-weight: 800;
  font-size: 22px;
  padding: 22px 28px;
}

.lp-about__body p { margin: 0 0 16px; font-size: 16px; }

.lp-about__body strong { color: var(--navy); }

.lp-about__body em { font-style: normal; border-bottom: 2px solid var(--accent); padding-bottom: 1px; }

@media (max-width: 760px) {
  .lp-about__grid { grid-template-columns: 1fr; }
}

/* ------- Exams ------- */

.lp-exams__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
}

.lp-exam {
  background: #fff;
  border: 1px solid var(--line);
  padding: 28px 24px;
  position: relative;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.lp-exam:hover {
  transform: translateY(-2px);
  box-shadow: 0 14px 32px -16px rgba(14, 37, 90, 0.25);
}

.lp-exam__code {
  display: inline-block;
  background: var(--navy);
  color: #fff;
  font-weight: 800;
  font-size: 13px;
  letter-spacing: 0.14em;
  padding: 4px 10px;
  margin-bottom: 14px;
}

.lp-exam__title {
  font-size: 19px;
  font-weight: 800;
  color: var(--navy-deep);
  margin: 0 0 6px;
  line-height: 1.4;
}

.lp-exam__level {
  font-size: 13px;
  color: var(--accent);
  font-weight: 700;
  margin: 0 0 14px;
  letter-spacing: 0.04em;
}

.lp-exam__desc {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0 0 14px;
  line-height: 1.75;
}

.lp-exam__topics {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.lp-exam__topics li {
  background: var(--tint);
  color: var(--navy);
  font-size: 12px;
  padding: 4px 10px;
  border-radius: 999px;
  font-weight: 600;
}

/* ------- Steps ------- */

.lp-steps__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  counter-reset: lp-step;
}

.lp-step {
  background: #fff;
  border: 1px solid var(--line);
  padding: 36px 28px;
  position: relative;
}

.lp-step__num {
  font-size: 36px;
  font-weight: 800;
  color: var(--accent);
  letter-spacing: 0.05em;
  margin-bottom: 10px;
  font-family: -apple-system, Helvetica, Arial, sans-serif;
}

.lp-step__title {
  font-size: 20px;
  font-weight: 800;
  color: var(--navy-deep);
  margin: 0 0 10px;
}

.lp-step__body {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0;
}

@media (max-width: 760px) {
  .lp-steps__list { grid-template-columns: 1fr; }
}

/* ------- Features ------- */

.lp-features { background: var(--bg-soft); max-width: none; }
.lp-features > .lp-section__head,
.lp-features > .lp-features__grid {
  max-width: var(--max);
  margin-left: auto;
  margin-right: auto;
}

.lp-features__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 28px;
}

.lp-feature {
  padding: 24px 20px;
  border-left: 4px solid var(--accent);
  background: #fff;
}

.lp-feature__title {
  font-size: 18px;
  font-weight: 800;
  color: var(--navy-deep);
  margin: 0 0 10px;
}

.lp-feature__body {
  font-size: 14px;
  color: var(--ink-soft);
  margin: 0;
}

/* ------- Partners ------- */

.lp-partners__list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 16px;
}

.lp-partner {
  background: #fff;
  border: 1px solid var(--line);
  padding: 28px 16px;
  text-align: center;
  font-weight: 700;
  color: var(--navy-deep);
  font-size: 15px;
}

/* ------- Voices ------- */

.lp-voices { background: var(--navy); color: #fff; max-width: none; }
.lp-voices > .lp-section__head,
.lp-voices > .lp-voices__grid {
  max-width: var(--max);
  margin-left: auto;
  margin-right: auto;
}
.lp-voices .lp-h2,
.lp-voices .lp-h2__en,
.lp-voices .lp-h2__jp { color: #fff; }
.lp-voices .lp-h2__sep { color: rgba(255, 255, 255, 0.4); }

.lp-voices__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 24px;
}

.lp-voice {
  margin: 0;
  background: rgba(255, 255, 255, 0.08);
  padding: 28px;
  border-left: 3px solid var(--accent);
}

.lp-voice__quote {
  margin: 0 0 14px;
  font-size: 15px;
  line-height: 1.85;
  font-style: normal;
}

.lp-voice__quote::before { content: "“"; font-size: 28px; margin-right: 4px; opacity: 0.7; }

.lp-voice__who {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.75);
  font-weight: 600;
}

/* ------- FAQ ------- */

.lp-faq__list { display: grid; gap: 12px; }

.lp-faq__item {
  background: #fff;
  border: 1px solid var(--line);
  padding: 18px 24px;
}

.lp-faq__item[open] { border-color: var(--accent); }

.lp-faq__q {
  font-weight: 700;
  font-size: 16px;
  color: var(--navy-deep);
  cursor: pointer;
  list-style: none;
  position: relative;
  padding-right: 32px;
}

.lp-faq__q::-webkit-details-marker { display: none; }

.lp-faq__q::after {
  content: "+";
  position: absolute;
  right: 0;
  top: 0;
  font-size: 22px;
  color: var(--accent);
  transition: transform 0.15s ease;
}

.lp-faq__item[open] .lp-faq__q::after { content: "−"; }

.lp-faq__a {
  margin: 12px 0 0;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.85;
}

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

.lp-cta {
  background: linear-gradient(135deg, var(--navy-deep) 0%, var(--navy) 60%, var(--accent) 100%);
  color: #fff;
}

.lp-cta__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 88px var(--pad);
  text-align: center;
}

.lp-cta__en {
  font-size: clamp(24px, 3vw, 36px);
  letter-spacing: 0.18em;
  font-weight: 800;
  margin: 0 0 10px;
}

.lp-cta__title {
  font-size: clamp(24px, 3.4vw, 36px);
  margin: 0 0 16px;
  font-weight: 800;
}

.lp-cta__lead {
  font-size: 16px;
  margin: 0 0 28px;
  color: rgba(255, 255, 255, 0.9);
}

.lp-cta__btns {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  justify-content: center;
}

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

.lp-footer { background: #0a1730; color: #c7cfdd; }

.lp-footer__inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 44px var(--pad);
  display: grid;
  grid-template-columns: auto 1fr auto;
  align-items: center;
  gap: 24px;
}

.lp-footer__brand svg { height: 40px; }
.lp-footer__brand svg text { fill: #fff; }
.lp-footer__brand svg circle:first-child { fill: #fff; }
.lp-footer__brand svg circle:nth-child(2) { stroke: var(--accent); }
.lp-footer__brand svg g text { fill: var(--navy); }

.lp-footer__copy { margin: 0; font-size: 12px; color: #8290a8; }

.lp-footer__nav {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  justify-content: flex-end;
}

.lp-footer__nav a {
  color: #c7cfdd;
  text-decoration: none;
  font-size: 13px;
}

.lp-footer__nav a:hover { color: #fff; }

@media (max-width: 760px) {
  .lp-footer__inner { grid-template-columns: 1fr; text-align: center; }
  .lp-footer__nav { justify-content: center; }
}