/* ===== Design Tokens ===== */
:root {
  /* === Colors (Clean / Trustworthy: Blue & White base) === */
  --color-primary: #1E3A8A;
  --color-primary-light: #3B82F6;
  --color-primary-dark: #0F2557;
  --color-bg: #FFFFFF;
  --color-bg-alt: #F8FAFC;
  --color-text: #0F172A;
  --color-text-muted: #64748B;
  --color-border: #E2E8F0;
  --color-accent: #F59E0B;

  /* === Typography === */
  --font-ja: "Noto Sans JP", sans-serif;
  --font-en: "Inter", sans-serif;
  --font-body: "Noto Sans JP", "Inter", sans-serif;

  /* Font Sizes (rem / root 16px) */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;

  /* Line Height */
  --leading-tight: 1.25;
  --leading-normal: 1.7;

  /* === Spacing === */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* === Layout === */
  --max-width: 1200px;
  --max-width-narrow: 800px;
  --container-padding: clamp(1rem, 4vw, 2rem);

  /* === Border Radius === */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 16px;

  /* === Shadows === */
  --shadow-sm: 0 1px 2px rgba(15, 23, 42, 0.05);
  --shadow-md: 0 4px 12px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 10px 30px rgba(15, 23, 42, 0.12);

  /* === Transitions === */
  --transition-base: 0.2s ease;
  --transition-slow: 0.4s ease;
}

/* ===== Reset ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--color-primary-light);
  text-decoration: none;
  transition: color var(--transition-base);
}

a:hover {
  color: var(--color-primary);
}

ul, ol {
  list-style: none;
}

/* ===== Focus Styles (Accessibility) ===== */
:focus-visible {
  outline: 3px solid var(--color-primary-light);
  outline-offset: 2px;
}

/* ===== Common Components ===== */

/* Container */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

/* Section */
.section {
  padding: var(--space-16) 0;
}

.section--alt {
  background-color: var(--color-bg-alt);
}

.section__header {
  text-align: center;
  margin-bottom: var(--space-12);
}

.section__title {
  font-size: var(--text-3xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-4);
  line-height: var(--leading-tight);
}

.section__subtitle {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

@media (min-width: 768px) {
  .section {
    padding: var(--space-20) 0;
  }

  .section__title {
    font-size: var(--text-4xl);
  }
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-3) var(--space-6);
  font-family: var(--font-body);
  font-size: var(--text-base);
  font-weight: 500;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: background-color var(--transition-base), transform var(--transition-base);
  text-decoration: none;
  line-height: 1.5;
}

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

.btn:active {
  transform: translateY(0);
}

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

.btn--primary:hover {
  background-color: var(--color-primary-dark);
  color: #FFFFFF;
}

.btn--large {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-lg);
}

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

.btn--accent:hover {
  background-color: #E08E00;
}

/* ===== Site Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(8px);
  transition: box-shadow var(--transition-base);
}

.site-header--scrolled {
  box-shadow: var(--shadow-md);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-4) var(--container-padding);
}

.site-header__logo {
  font-family: var(--font-en);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  text-decoration: none;
  letter-spacing: 0.02em;
}

.site-header__logo:hover {
  color: var(--color-primary);
}

.site-header__nav {
  display: none;
}

.site-header__nav ul {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.site-header__nav a {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text);
  transition: color var(--transition-base);
}

.site-header__nav a:hover {
  color: var(--color-primary-light);
}

.site-header__nav .btn {
  font-size: var(--text-sm);
  padding: var(--space-2) var(--space-4);
}

/* Hamburger Menu Toggle */
.site-header__menu-toggle {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.site-header__menu-toggle span {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 1px;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.site-header__menu-toggle.is-active span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.site-header__menu-toggle.is-active span:nth-child(2) {
  opacity: 0;
}

.site-header__menu-toggle.is-active span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* Mobile Navigation */
.mobile-nav {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(255, 255, 255, 0.98);
  z-index: 99;
  padding-top: 80px;
}

.mobile-nav.is-open {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.mobile-nav ul {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-8);
}

.mobile-nav a {
  font-size: var(--text-xl);
  font-weight: 500;
  color: var(--color-text);
}

.mobile-nav a:hover {
  color: var(--color-primary-light);
}

.mobile-nav .btn {
  margin-top: var(--space-4);
}

@media (min-width: 1024px) {
  .site-header__nav {
    display: block;
  }

  .site-header__menu-toggle {
    display: none;
  }
}

/* ===== Hero Section ===== */
.hero {
  position: relative;
  min-height: 80vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 50%, var(--color-primary-light) 100%);
  color: #FFFFFF;
  text-align: center;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: radial-gradient(circle at 30% 50%, rgba(255, 255, 255, 0.08) 0%, transparent 60%);
  pointer-events: none;
}

.hero__inner {
  position: relative;
  max-width: var(--max-width-narrow);
  margin: 0 auto;
  padding: var(--space-16) var(--container-padding);
}

.hero__title {
  font-size: var(--text-4xl);
  font-weight: 700;
  line-height: var(--leading-tight);
  margin-bottom: var(--space-6);
  letter-spacing: 0.04em;
}

.hero__subtitle {
  font-size: var(--text-lg);
  line-height: var(--leading-normal);
  margin-bottom: var(--space-8);
  opacity: 0.9;
}

.hero__cta .btn {
  font-size: var(--text-lg);
  padding: var(--space-4) var(--space-8);
  background-color: var(--color-accent);
  color: var(--color-text);
  font-weight: 700;
}

.hero__cta .btn:hover {
  background-color: #E08E00;
  color: var(--color-text);
}

@media (min-width: 768px) {
  .hero {
    min-height: 90vh;
  }

  .hero__title {
    font-size: var(--text-5xl);
  }

  .hero__subtitle {
    font-size: var(--text-xl);
  }
}

/* ===== Problem Section ===== */
.problem {
  background-color: var(--color-bg-alt);
}

.problem__cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
  margin-bottom: var(--space-8);
}

.problem-card {
  background-color: var(--color-bg);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  box-shadow: var(--shadow-sm);
  text-align: center;
  transition: box-shadow var(--transition-base);
}

.problem-card:hover {
  box-shadow: var(--shadow-md);
}

.problem-card__icon {
  font-size: var(--text-4xl);
  margin-bottom: var(--space-4);
}

.problem-card__text {
  font-size: var(--text-lg);
  font-weight: 500;
  color: var(--color-text);
  line-height: var(--leading-normal);
}

.problem__closing {
  text-align: center;
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-primary);
}

@media (min-width: 768px) {
  .problem__cards {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ===== Services Section ===== */
.services__cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
  margin-bottom: var(--space-8);
}

.service-card {
  background-color: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  transition: box-shadow var(--transition-base);
}

.service-card:hover {
  box-shadow: var(--shadow-md);
}

.service-card__icon {
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--color-bg-alt);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
  font-size: var(--text-2xl);
}

.service-card__title {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.service-card__desc {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.service-card__list {
  margin-bottom: var(--space-4);
  padding-left: var(--space-4);
}

.service-card__list li {
  position: relative;
  padding-left: var(--space-4);
  margin-bottom: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-text);
}

.service-card__list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 6px;
  height: 6px;
  background-color: var(--color-primary-light);
  border-radius: 50%;
}

.service-card__note {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.service-card__price {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-primary);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-border);
}

.service-card__price a {
  color: var(--color-primary);
  font-weight: 700;
}

.services__more {
  text-align: center;
  font-size: var(--text-lg);
  color: var(--color-text-muted);
}

.services__more a {
  font-weight: 700;
}

@media (min-width: 768px) {
  .services__cards {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* ===== Testimonials Section ===== */
.testimonials {
  background-color: var(--color-bg-alt);
}

.testimonials__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
}

.testimonial-card {
  background-color: var(--color-bg);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.testimonial-card__video {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
}

.testimonial-card__video iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

.testimonial-card__info {
  padding: var(--space-6);
}

.testimonial-card__name {
  font-size: var(--text-base);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.testimonial-card__title {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--space-3);
}

.testimonial-card__comment {
  font-size: var(--text-sm);
  color: var(--color-text);
  font-style: italic;
}

@media (min-width: 768px) {
  .testimonials__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* ===== Lectures Section ===== */
.lectures-gallery {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
}

.lecture-item {
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.lecture-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.lecture-item img {
  width: 100%;
  aspect-ratio: 3 / 2;
  object-fit: cover;
}

.lecture-item figcaption {
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  background-color: var(--color-bg);
}

@media (min-width: 768px) {
  .lectures-gallery {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* Lightbox */
.lightbox {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.9);
  z-index: 200;
  align-items: center;
  justify-content: center;
  cursor: pointer;
}

.lightbox.is-open {
  display: flex;
}

.lightbox__img {
  max-width: 90vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: var(--radius-md);
}

.lightbox__close {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  color: #FFFFFF;
  font-size: var(--text-2xl);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ===== Profile Section ===== */
.profile {
  background-color: var(--color-bg-alt);
}

.profile__content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
  align-items: start;
}

.profile__image img {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  object-fit: cover;
  margin: 0 auto;
  box-shadow: var(--shadow-md);
}

.profile__name {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.profile__name span {
  font-size: var(--text-lg);
  font-weight: 400;
  color: var(--color-text-muted);
}

.profile__role {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}

.profile__bio h3,
.profile__message h3 {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}

.profile__bio ul {
  padding-left: var(--space-4);
  margin-bottom: var(--space-6);
}

.profile__bio li {
  position: relative;
  padding-left: var(--space-4);
  margin-bottom: var(--space-2);
  font-size: var(--text-base);
}

.profile__bio li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.65em;
  width: 6px;
  height: 6px;
  background-color: var(--color-primary-light);
  border-radius: 50%;
}

.profile__message p {
  font-size: var(--text-base);
  line-height: var(--leading-normal);
}

@media (min-width: 768px) {
  .profile__content {
    grid-template-columns: 1fr 2fr;
  }

  .profile__image img {
    width: 250px;
    height: 250px;
    margin: 0;
  }
}

/* ===== Company Section ===== */
.company__table {
  max-width: var(--max-width-narrow);
  margin: 0 auto;
}

.company__row {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-1);
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--color-border);
}

.company__row dt {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-primary);
}

.company__row dd {
  font-size: var(--text-base);
  color: var(--color-text);
}

@media (min-width: 768px) {
  .company__row {
    grid-template-columns: 160px 1fr;
    gap: var(--space-4);
  }
}

/* ===== Contact Section ===== */
.contact {
  background: linear-gradient(135deg, var(--color-primary-dark) 0%, var(--color-primary) 100%);
  color: #FFFFFF;
  text-align: center;
}

.contact .section__title {
  color: #FFFFFF;
}

.contact .section__subtitle {
  color: rgba(255, 255, 255, 0.85);
}

.contact__methods {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  max-width: 480px;
  margin: 0 auto var(--space-6);
}

.contact__btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-6);
  border-radius: var(--radius-md);
  font-size: var(--text-lg);
  font-weight: 700;
  text-decoration: none;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.contact__btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.contact__btn--email {
  background-color: #FFFFFF;
  color: var(--color-primary);
}

.contact__btn--email:hover {
  color: var(--color-primary-dark);
}

.contact__btn--tel {
  background-color: rgba(255, 255, 255, 0.15);
  color: #FFFFFF;
  border: 2px solid rgba(255, 255, 255, 0.4);
}

.contact__btn--tel:hover {
  background-color: rgba(255, 255, 255, 0.25);
  color: #FFFFFF;
}

.contact__icon {
  font-size: var(--text-xl);
}

.contact__hours {
  font-size: var(--text-sm);
  color: rgba(255, 255, 255, 0.7);
}

@media (min-width: 768px) {
  .contact__methods {
    flex-direction: row;
    max-width: 600px;
  }

  .contact__btn {
    flex: 1;
  }
}

/* ===== Footer ===== */
.site-footer {
  background-color: var(--color-primary-dark);
  color: rgba(255, 255, 255, 0.7);
  text-align: center;
  padding: var(--space-8) var(--container-padding);
}

.site-footer__name {
  font-family: var(--font-en);
  font-size: var(--text-sm);
  font-weight: 500;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: var(--space-2);
}

.site-footer__copy {
  font-size: var(--text-xs);
}

.site-footer__links {
  margin-top: var(--space-4);
}

.site-footer__links a {
  font-size: var(--text-xs);
  color: rgba(255, 255, 255, 0.6);
}

.site-footer__links a:hover {
  color: #FFFFFF;
}

/* ===== Fade-in Animation ===== */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.fade-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}