/* ============================
   Variables & Reset
   ============================ */
:root {
  --bg: #FFFFFF;
  --primary: #FCD13E;
  --secondary: #009FE8;
  --accent: #009D95;
  --text: #1a1a2e;
  --text-light: #555;
  --gray-light: #f5f5f7;
  --radius: 12px;
  --transition: 0.6s cubic-bezier(0.22, 1, 0.36, 1);
}

*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  max-width: 100%;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: 'LINE Seed JP', sans-serif;
  color: var(--text);
  background: var(--bg);
  overflow-x: hidden;
  line-height: 1.8;
  width: 100%;
}

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

ul {
  list-style: none;
}

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

strong {
  background: linear-gradient(transparent 55%, rgba(252, 209, 62, 0.5) 55%);
  font-weight: 700;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

.sp-only {
  display: none;
}

/* ============================
   Header
   ============================ */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transition: transform 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

.header--hidden {
  transform: translateY(-100%);
}

.header__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header__logo {
  display: flex;
  align-items: center;
  flex-shrink: 0;
}

.header__logo img {
  height: 48px;
  width: auto;
  display: block;
}

.header__nav {
  display: flex;
  align-items: center;
  gap: 28px;
  font-size: 0.875rem;
  font-weight: 700;
}

.header__nav a {
  position: relative;
  transition: color 0.3s;
}

.header__nav a:not(.header__cta-btn)::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--secondary);
  transition: width 0.3s;
}

.header__nav a:not(.header__cta-btn):hover::after {
  width: 100%;
}

.header__cta-btn {
  background: var(--primary);
  color: var(--text) !important;
  padding: 8px 20px;
  border-radius: 100px;
  font-weight: 700;
  transition: transform 0.3s, box-shadow 0.3s;
}

.header__cta-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(252, 209, 62, 0.4);
}

/* hamburger removed - using section label on SP instead */

/* ============================
   Buttons
   ============================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  border-radius: 100px;
  transition: transform 0.3s, box-shadow 0.3s;
  cursor: pointer;
  border: none;
  font-family: inherit;
}

.btn--primary {
  background: var(--primary);
  color: var(--text);
}

.btn--lg {
  padding: 16px 36px;
  font-size: 1.05rem;
}

.btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(252, 209, 62, 0.35);
}

.btn__arrow {
  transition: transform 0.3s;
}

.btn:hover .btn__arrow {
  transform: translateX(4px);
}

/* ============================
   Hero
   ============================ */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 120px 24px 80px;
  overflow: hidden;
  background: linear-gradient(160deg, #f8f9ff 0%, #eef7ff 50%, #f0fffe 100%);
}

.hero__bg-grid {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 159, 232, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 159, 232, 0.06) 1px, transparent 1px);
  background-size: 60px 60px;
  animation: gridMove 20s linear infinite;
}

@keyframes gridMove {
  0% {
    transform: translate(0, 0);
  }

  100% {
    transform: translate(60px, 60px);
  }
}

.hero__content {
  position: relative;
  text-align: center;
  max-width: 800px;
}

.hero__label {
  display: inline-block;
  background: var(--secondary);
  color: #fff;
  padding: 6px 20px;
  border-radius: 100px;
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 28px;
  animation: fadeInDown 0.8s ease-out;
}

.hero__title {
  font-family: 'Noto Sans JP', sans-serif;
  font-size: clamp(1.6rem, 5vw, 3rem);
  font-weight: 900;
  line-height: 2;
  margin-bottom: 24px;
}

.hero__title-line {
  display: block;
  animation: fadeInUp 0.8s ease-out both;
}

.hero__title-line:nth-child(1) {
  animation-delay: 0.2s;
}

.hero__title-line:nth-child(2) {
  animation-delay: 0.4s;
}

.hero__title-line:nth-child(3) {
  animation-delay: 0.6s;
}

.hero__title-accent {
  color: var(--secondary);
  position: relative;
  width: fit-content;
  margin: 0 auto;
}

.hero__title-accent::after {
  content: '';
  position: absolute;
  bottom: 0.25em;
  left: -4px;
  right: -4px;
  height: 0.4em;
  background: var(--primary);
  opacity: 0.4;
  z-index: -1;
  border-radius: 4px;
}

.hero__sub {
  font-size: 1.05rem;
  color: var(--text-light);
  margin-bottom: 40px;
  animation: fadeInUp 0.8s ease-out 0.8s both;
  line-height: 2;
}

.hero__cta {
  animation: fadeInUp 0.8s ease-out 1s both;
}

.hero__scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-size: 1rem;
  color: var(--text-light);
  letter-spacing: 0.1em;
  text-align: center;
  animation: scrollHintFadeIn 0.8s ease-out 1.2s both;
}

@keyframes scrollHintFadeIn {
  from {
    opacity: 0;
    transform: translate(-50%, 20px);
  }

  to {
    opacity: 1;
    transform: translate(-50%, 0);
  }
}

.hero__scroll-line {
  width: 1px;
  height: 40px;
  background: var(--secondary);
  animation: scrollLine 1.5s ease-in-out infinite;
}

@keyframes scrollLine {
  0% {
    transform: scaleY(0);
    transform-origin: top;
  }

  50% {
    transform: scaleY(1);
    transform-origin: top;
  }

  51% {
    transform-origin: bottom;
  }

  100% {
    transform: scaleY(0);
    transform-origin: bottom;
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ============================
   Sections (Common)
   ============================ */
.section {
  padding: 100px 0;
  overflow-x: hidden;
  position: relative;
}

.section__header {
  text-align: center;
  margin-bottom: 60px;
}

.section__number {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--secondary);
  background: rgba(0, 159, 232, 0.08);
  padding: 4px 16px;
  border-radius: 100px;
  margin-bottom: 16px;
  letter-spacing: 0.1em;
}

.section__title {
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  font-weight: 900;
  line-height: 1.6;
}

/* ============================
   Reveal Animations
   ============================ */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity var(--transition), transform var(--transition);
}

.reveal--left {
  transform: translateX(-60px);
}

.reveal--right {
  transform: translateX(60px);
}

.reveal--up {
  transform: translateY(60px);
}

.reveal.is-visible {
  opacity: 1;
  transform: translate(0, 0);
}

/* stagger delay for cards */
.reveal[style*="--delay: 1"] {
  transition-delay: 0.15s;
}

.reveal[style*="--delay: 2"] {
  transition-delay: 0.3s;
}

.reveal[style*="--delay: 3"] {
  transition-delay: 0.45s;
}

/* ============================
   Section: Problem
   ============================ */
.section--problem {
  background: var(--gray-light);
}

.problem__intro {
  max-width: 960px;
  margin: 0 auto 60px;
  display: flex;
  align-items: center;
  gap: 40px;
  font-size: 1.05rem;
  line-height: 2;
}

.problem__intro-text {
  flex: 1;
}

.problem__intro-img {
  flex: 1;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.problem__intro-img img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
}

.problem__note {
  margin-top: 20px;
  background: #fff;
  border-left: 4px solid var(--accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 20px 28px;
  text-align: left;
}

.problem__note-label {
  display: inline-block;
  background: var(--accent);
  color: #fff;
  padding: 2px 12px;
  border-radius: 4px;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 8px;
}

.problem__note p {
  font-size: 1rem;
  color: var(--text-light);
  line-height: 1.8;
}

.problem__note-link {
  display: inline-block;
  margin-top: 8px;
  color: var(--accent);
  font-weight: 700;
  font-size: 0.85rem;
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: opacity 0.2s;
}

.problem__note-link:hover {
  opacity: 0.7;
}

.problem__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
}

.problem__card {
  background: #fff;
  border-radius: var(--radius);
  padding: 40px 32px;
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.04);
  transition: transform 0.3s, box-shadow 0.3s;
}

.problem__card:hover {
  transform: translateY(-6px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
}

.problem__icon {
  width: 56px;
  height: 56px;
  color: var(--secondary);
  margin-bottom: 20px;
}

.problem__card h3 {
  font-size: 1.2rem;
  margin-bottom: 12px;
  color: var(--text);
}

.problem__card p {
  color: var(--text-light);
  font-size: 1rem;
  line-height: 1.9;
}

.problem__message {
  grid-column: 1 / -1;
  text-align: center;
  background: linear-gradient(135deg, var(--secondary), var(--accent));
  color: #fff;
  border-radius: var(--radius);
  padding: 40px 16px;
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 2;
}

.problem__message strong {
  font-size: 1.15rem;
}

/* ============================
   Section: Solution
   ============================ */
.solution__content {
  max-width: 880px;
  margin: 0 auto;
}

.solution__badge {
  display: block;
  width: fit-content;
  margin: 0 auto 28px;
  background: var(--primary);
  color: var(--text);
  padding: 6px 20px;
  border-radius: 100px;
  font-size: 0.85rem;
  font-weight: 700;
  text-align: center;
}

.solution__info-wrapper {
  display: flex;
  align-items: center;
  gap: 40px;
  margin-bottom: 60px;
}

.solution__info {
  flex: 1;
}

.solution__info-img {
  flex: 1;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.solution__info-img img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
}

.solution__info h3 {
  font-size: 1.3rem;
  margin-bottom: 16px;
}

.solution__info p {
  color: var(--text-light);
  line-height: 2;
}

.solution__info strong {
  color: var(--secondary);
}

.solution__timeline {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  flex-wrap: wrap;
}

.solution__step {
  background: var(--gray-light);
  border-radius: var(--radius);
  padding: 28px 24px;
  text-align: center;
  flex: 1;
  min-width: 180px;
  transition: transform 0.3s, box-shadow 0.3s;
}

.solution__step:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.06);
}

.solution__step-num {
  font-weight: 900;
  font-size: 1.1rem;
  color: var(--secondary);
  margin-bottom: 8px;
}

.solution__step p {
  font-size: 1rem;
  color: var(--text-light);
}

.solution__step-arrow {
  font-size: 1.5rem;
  color: var(--accent);
  font-weight: 700;
}

/* ============================
   Section: Advantage
   ============================ */
.section--advantage {
  background: var(--gray-light);
}

.advantage__comparison {
  display: flex;
  align-items: stretch;
  gap: 0;
}

.advantage__col {
  flex: 1;
  padding: 40px 32px;
  border-radius: var(--radius);
}

.advantage__col--other {
  background: #fff;
  border: 2px solid #e0e0e0;
}

.advantage__col--hack {
  background: linear-gradient(135deg, rgba(0, 159, 232, 0.04), rgba(0, 157, 149, 0.04));
  border: 2px solid var(--secondary);
  position: relative;
}

.advantage__col--hack::before {
  position: absolute;
  top: -12px;
  right: 24px;
  background: var(--primary);
  color: var(--text);
  padding: 4px 16px;
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 700;
}

.advantage__col-label {
  font-weight: 900;
  font-size: 1.15rem;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 2px solid currentColor;
}

.advantage__col--other .advantage__col-label {
  color: var(--text-light);
  border-color: #e0e0e0;
}

.advantage__col--hack .advantage__col-label {
  color: var(--secondary);
  border-color: var(--secondary);
}

.advantage__col li {
  padding: 12px 0;
  border-bottom: 1px solid rgba(0, 0, 0, 0.05);
  font-size: 1rem;
  line-height: 1.7;
}

.advantage__col--other li {
  color: var(--text-light);
}

.advantage__col--hack li strong {
  display: block;
  color: var(--accent);
  font-size: 1rem;
  margin-bottom: 4px;
}

.advantage__col--hack li span {
  color: var(--text-light);
  font-size: 1rem;
}

.advantage__vs {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 56px;
  min-width: 56px;
  font-weight: 900;
  font-size: 1.1rem;
  color: var(--text-light);
}

/* ============================
   Section: Curriculum
   ============================ */
.curriculum__cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 28px;
}

.curriculum__card {
  background: #fff;
  border-radius: var(--radius);
  box-shadow: 0 2px 20px rgba(0, 0, 0, 0.04);
  transition: transform 0.3s, box-shadow 0.3s;
  position: relative;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.curriculum__card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--secondary), var(--accent));
  transform: scaleX(0);
  transition: transform 0.4s ease;
  z-index: 1;
}

.curriculum__card.is-visible::before {
  transform: scaleX(1);
}

.curriculum__card:hover {
  transform: translateY(-8px);
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.1);
}

.curriculum__card-img {
  width: 100%;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--gray-light);
}

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

.curriculum__card-body {
  padding: 28px 24px;
  flex: 1;
}

.curriculum__card-body h3 {
  font-size: 1.15rem;
  margin-bottom: 16px;
}

.curriculum__card-body p {
  color: var(--text-light);
  font-size: 1rem;
  line-height: 1.9;
}

/* ============================
   Section: CTA Final
   ============================ */
.section--cta {
  background: linear-gradient(160deg, var(--secondary), var(--accent));
  color: #fff;
  text-align: center;
  padding: 100px 0;
}

.cta__title {
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  font-weight: 900;
  line-height: 1.6;
  margin-bottom: 20px;
}

.cta__sub {
  font-size: 1.05rem;
  opacity: 0.9;
  margin-bottom: 40px;
}

.section--cta .btn--primary {
  background: var(--primary);
  color: var(--text);
}

/* ============================
   Footer
   ============================ */
.footer {
  background: var(--text);
  color: #fff;
  padding: 40px 0;
}

.footer__inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
  text-align: center;
}

.footer__info {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
}

.footer__logo img {
  height: 40px;
  width: auto;
  filter: brightness(0) invert(1);
}

.footer__name {
  font-size: 0.95rem;
  font-weight: 700;
}

.footer__address {
  font-style: normal;
  font-size: 0.85rem;
  line-height: 1.7;
  opacity: 0.7;
}

.footer__tel {
  font-size: 0.85rem;
  opacity: 0.7;
}

.footer__tel a {
  color: inherit;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.footer__copy {
  font-size: 0.75rem;
  opacity: 0.5;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  width: 100%;
}

/* ============================
   Active Section Indicator
   ============================ */
.section.is-active-section::after {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(to bottom, var(--secondary), var(--accent));
  animation: slideDown 0.6s ease-out;
}

@keyframes slideDown {
  from {
    transform: scaleY(0);
    transform-origin: top;
  }

  to {
    transform: scaleY(1);
    transform-origin: top;
  }
}

/* ============================
   Section Indicator Bar
   ============================ */
.section-indicator {
  position: fixed;
  top: 80px;
  left: 0;
  width: 100%;
  z-index: 99;
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transform: translateY(-100%);
  transition: transform 0.35s cubic-bezier(0.22, 1, 0.36, 1);
  overflow: hidden;
}

.section-indicator.is-visible {
  transform: translateY(0);
}

/* ヘッダーが隠れたらtop:0に移動 */
.section-indicator.is-header-hidden {
  top: 0;
}

.section-indicator__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  height: 40px;
  display: flex;
  align-items: center;
  overflow: hidden;
}

.section-indicator__track {
  display: flex;
  align-items: center;
  gap: 0;
  white-space: nowrap;
  transition: transform 0.7s cubic-bezier(0.22, 1, 0.36, 1);
  will-change: transform;
}

.section-indicator__item {
  font-size: 1rem;
  font-weight: 700;
  color: var(--text);
  opacity: 0.25;
  flex-shrink: 0;
  transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}

.section-indicator__item.is-active {
  opacity: 1;
}

.section-indicator__item.is-past {
  opacity: 0;
}

.section-indicator__separator {
  flex-shrink: 0;
  margin: 0 16px;
  font-size: 0.85rem;
  color: var(--text);
  opacity: 0.15;
  transition: opacity 0.7s cubic-bezier(0.22, 1, 0.36, 1);
}

.section-indicator__separator.is-past {
  opacity: 0;
}

/* ============================
   Responsive
   ============================ */
@media (max-width: 768px) {
  .sp-only {
    display: inline;
  }

  .header__inner {
    height: 56px;
    padding: 0 16px;
  }

  .header__logo img {
    height: 36px;
  }

  .header__nav {
    display: none;
  }

  .section-indicator {
    top: 56px;
  }

  .problem__grid {
    grid-template-columns: 1fr;
  }

  .problem__intro,
  .solution__info-wrapper {
    flex-direction: column;
    gap: 24px;
    text-align: center;
  }

  .problem__note {
    text-align: left;
  }

  .advantage__comparison {
    flex-direction: column;
    gap: 24px;
  }

  .advantage__vs {
    width: auto;
    min-width: auto;
    padding: 8px 0;
  }

  .curriculum__cards {
    grid-template-columns: 1fr;
  }

  .solution__timeline {
    flex-direction: column;
  }

  .solution__step-arrow {
    transform: rotate(90deg);
  }

  .footer__inner {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }

  .section.is-active-section::after {
    display: none;
  }
}