/* ============================================
   masatotahara.com — Style Sheet
   Design Guide: 「夜明け前の図書館」
   ============================================ */

/* --- Google Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Cormorant+Garamond:ital,wght@0,300;0,400;0,600;1,400&family=Noto+Serif+JP:wght@200;300;400;600&display=swap');

/* --- Custom Properties --- */
:root {
  /* Colors */
  --color-primary:       #1a2639;
  --color-primary-light: #3d5a80;
  --color-accent:        #c77b3c;
  --color-accent-soft:   #d4a574;
  --color-bg:            #f5f0eb;
  --color-surface:       #eae4dc;
  --color-surface-dark:  #ddd5ca;
  --color-text:          #2c3e50;
  --color-text-light:    #c8c0b8;

  /* Typography */
  --font-jp: 'Noto Serif JP', '游明朝', 'YuMincho', serif;
  --font-en: 'Cormorant Garamond', Georgia, serif;
  --line-height-body: 2.0;
  --line-height-heading: 1.4;

  /* Spacing */
  --section-padding: 120px;
  --content-max-width: 960px;
  --content-padding: 40px;

  /* Animation */
  --transition-slow: 0.8s ease;
  --transition-base: 0.3s ease;
}

@media (max-width: 768px) {
  :root {
    --section-padding: 80px;
    --content-padding: 20px;
  }
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-jp);
  font-weight: 300;
  font-size: 1.125rem;
  line-height: var(--line-height-body);
  color: var(--color-text);
  background: 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;
  border-bottom: 1px solid transparent;
  transition: border-color var(--transition-base);
}

a:hover {
  border-bottom-color: var(--color-accent);
}

h1, h2, h3, h4 {
  font-weight: 400;
  line-height: var(--line-height-heading);
  color: var(--color-primary);
}

/* --- Utility --- */
.container {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 var(--content-padding);
}

.text-center {
  text-align: center;
}

.divider {
  width: 60px;
  height: 1px;
  background: var(--color-accent);
  margin: 56px auto;
  opacity: 0.5;
}

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

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

/* stagger children */
.fade-in-group > .fade-in:nth-child(2) { transition-delay: 0.15s; }
.fade-in-group > .fade-in:nth-child(3) { transition-delay: 0.3s; }
.fade-in-group > .fade-in:nth-child(4) { transition-delay: 0.45s; }
.fade-in-group > .fade-in:nth-child(5) { transition-delay: 0.6s; }
.fade-in-group > .fade-in:nth-child(6) { transition-delay: 0.75s; }


/* ============================================
   Header / Navigation
   ============================================ */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 40px;
  background: transparent;
  transition: background 0.4s ease;
}

.site-header.scrolled {
  background: rgba(26, 38, 57, 0.95);
}

/* Subpage header: always dark */
.site-header.header-dark {
  background: var(--color-primary);
}

.site-logo a {
  border-bottom: none;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.site-logo a:hover {
  border-bottom: none;
}

.logo-jp {
  font-family: var(--font-jp);
  font-size: 1.125rem;
  font-weight: 400;
  color: var(--color-bg);
}

.logo-en {
  font-family: var(--font-en);
  font-size: 0.75rem;
  font-weight: 300;
  letter-spacing: 0.15em;
  color: var(--color-text-light);
}

.nav-links {
  display: flex;
  gap: 32px;
  list-style: none;
}

.nav-links a {
  font-family: var(--font-jp);
  font-size: 0.875rem;
  font-weight: 300;
  letter-spacing: 0.08em;
  color: var(--color-bg);
  border-bottom: none;
  transition: color var(--transition-base);
}

.nav-links a:hover {
  color: var(--color-accent);
  border-bottom: none;
}

/* Hamburger (SP) */
.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 12px;
  z-index: 110;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 1px;
  background: var(--color-bg);
  margin: 6px 0;
  transition: transform var(--transition-base), opacity var(--transition-base);
}

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

.hamburger.active span:nth-child(2) {
  opacity: 0;
}

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

/* Mobile menu overlay */
.mobile-menu {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--color-primary);
  z-index: 105;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 0;
  opacity: 0;
  transition: opacity 0.4s ease;
  pointer-events: none;
}

.mobile-menu.open {
  opacity: 1;
  pointer-events: auto;
}

.mobile-menu a {
  font-family: var(--font-jp);
  font-size: 1.25rem;
  font-weight: 300;
  color: var(--color-bg);
  padding: 20px 0;
  border-bottom: none;
  transition: color var(--transition-base);
}

.mobile-menu a:hover {
  color: var(--color-accent);
  border-bottom: none;
}

@media (max-width: 768px) {
  .site-header {
    padding: 0 20px;
  }

  .nav-links {
    display: none;
  }

  .hamburger {
    display: block;
  }

  .mobile-menu {
    display: flex;
  }
}


/* ============================================
   Section 1: Hero (#hero)
   ============================================ */
#hero {
  height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 0 var(--content-padding);
  background:
    linear-gradient(180deg,
      rgba(13, 21, 32, 0.85) 0%,
      rgba(26, 38, 57, 0.7) 50%,
      rgba(42, 58, 80, 0.85) 100%
    );
  /* When hero-bg.webp is available, uncomment:
    ,url('../images/hero-bg.webp') center/cover no-repeat; */
  background-color: var(--color-primary);
}

.hero-name-jp {
  font-family: var(--font-jp);
  font-size: 3.2rem;
  font-weight: 600;
  color: var(--color-bg);
  line-height: 1.3;
  opacity: 0;
  animation: heroFadeIn 1.2s ease 0.5s forwards;
}

.hero-name-en {
  font-family: var(--font-en);
  font-size: 1.25rem;
  font-weight: 300;
  letter-spacing: 0.2em;
  color: var(--color-text-light);
  margin-top: 8px;
  opacity: 0;
  animation: heroFadeIn 1.2s ease 0.8s forwards;
}

.hero-tagline {
  font-family: var(--font-jp);
  font-size: 1.5rem;
  font-weight: 200;
  line-height: 1.8;
  color: var(--color-text-light);
  margin-top: 48px;
  opacity: 0;
  animation: heroFadeIn 1.2s ease 1.5s forwards;
}

@keyframes heroFadeIn {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-scroll-indicator {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  width: 1px;
  height: 40px;
  background: var(--color-text-light);
  opacity: 0;
  animation: scrollPulse 2.5s ease-in-out 3s infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0; }
  50% { opacity: 0.5; }
}

@media (max-width: 768px) {
  .hero-name-jp {
    font-size: 2rem;
  }

  .hero-name-en {
    font-size: 1rem;
  }

  .hero-tagline {
    font-size: 1.125rem;
    margin-top: 32px;
  }
}


/* ============================================
   Section 2: Compassion (#compassion)
   ============================================ */
#compassion {
  background: linear-gradient(180deg, var(--color-primary) 0%, #2a3a50 100%);
  padding: 160px 0;
  text-align: center;
}

.compassion-text {
  max-width: 600px;
  margin: 0 auto;
  padding: 0 var(--content-padding);
}

.compassion-text p {
  font-family: var(--font-jp);
  font-size: 1.375rem;
  font-weight: 200;
  line-height: 2.2;
  color: var(--color-text-light);
}

#compassion .divider {
  margin: 56px auto;
}

@media (max-width: 768px) {
  #compassion {
    padding: 120px 0;
  }

  .compassion-text p {
    font-size: 1.125rem;
  }
}


/* ============================================
   Section 3: Resilience (#resilience)
   ============================================ */
#resilience {
  background: var(--color-bg);
  padding: var(--section-padding) 0;
}

.resilience-lead {
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--color-primary);
  margin-bottom: 16px;
}

.paradigm-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 24px;
  align-items: stretch;
  margin: 48px 0;
}

.paradigm-card {
  padding: 32px;
  border-radius: 8px;
}

.paradigm-card--mechanical {
  background: var(--color-surface);
  border: 1px solid var(--color-surface-dark);
}

.paradigm-card--life {
  background: var(--color-bg);
  border: 1px solid var(--color-surface-dark);
  border-left: 3px solid var(--color-accent);
}

.paradigm-card h3 {
  font-size: 1.125rem;
  font-weight: 400;
  margin-bottom: 16px;
}

.paradigm-card--life h3 {
  color: var(--color-accent);
}

.paradigm-card ul {
  list-style: none;
  font-size: 1rem;
  font-weight: 300;
  line-height: 2.0;
}

.paradigm-arrow {
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  color: var(--color-accent);
}

.resilience-body {
  margin-top: 56px;
  font-size: 1.125rem;
  font-weight: 300;
  line-height: 2.0;
  color: var(--color-text);
}

@media (max-width: 768px) {
  .paradigm-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .paradigm-arrow {
    font-size: 1.25rem;
    padding: 8px 0;
  }

  .resilience-lead {
    font-size: 1.25rem;
  }
}


/* ============================================
   Section 4: About (#about-section)
   ============================================ */
#about-section {
  background: var(--color-bg);
  padding: var(--section-padding) 0;
}

.about-grid {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 48px;
  align-items: start;
}

.about-portrait {
  width: 240px;
  height: 240px;
  border-radius: 50%;
  object-fit: cover;
  filter: saturate(0.3);
}

/* Placeholder when no photo yet */
.about-portrait-placeholder {
  width: 240px;
  height: 240px;
  border-radius: 50%;
  background: var(--color-surface);
  border: 1px solid var(--color-surface-dark);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary-light);
  font-size: 0.875rem;
}

.about-text p {
  margin-bottom: 24px;
}

.cta-link {
  display: inline-block;
  font-size: 1rem;
  font-weight: 400;
  color: var(--color-primary-light);
  letter-spacing: 0.1em;
  border-bottom: none;
  margin-top: 24px;
  transition: color var(--transition-base);
}

.cta-link span {
  display: inline-block;
  transition: transform var(--transition-base);
}

.cta-link:hover {
  color: var(--color-accent);
  border-bottom: none;
}

.cta-link:hover span {
  transform: translateX(4px);
}

@media (max-width: 768px) {
  .about-grid {
    grid-template-columns: 1fr;
    justify-items: center;
    gap: 32px;
  }

  .about-portrait,
  .about-portrait-placeholder {
    width: 180px;
    height: 180px;
  }

  .about-text {
    text-align: left;
  }
}


/* ============================================
   Section 5: Philosophy (#philosophy-section)
   ============================================ */
#philosophy-section {
  background: var(--color-surface);
  padding: var(--section-padding) 0;
}

.section-heading {
  font-size: 2rem;
  font-weight: 400;
  text-align: center;
  margin-bottom: 56px;
}

.philosophy-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.philosophy-card {
  background: var(--color-bg);
  border: 1px solid var(--color-surface-dark);
  border-radius: 8px;
  padding: 32px;
  transition:
    background var(--transition-base),
    border-left var(--transition-base);
}

.philosophy-card:hover {
  background: var(--color-surface);
  border-left: 3px solid var(--color-accent);
}

.philosophy-card h3 {
  font-size: 1.125rem;
  font-weight: 400;
  color: var(--color-primary);
  margin-bottom: 12px;
}

.philosophy-card p {
  font-size: 0.9375rem;
  font-weight: 300;
  line-height: 1.8;
  color: var(--color-text);
}

@media (max-width: 1023px) {
  .philosophy-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .philosophy-grid {
    grid-template-columns: 1fr;
  }

  .section-heading {
    font-size: 1.5rem;
    margin-bottom: 40px;
  }
}


/* ============================================
   Section 6: Projects (#projects-section)
   ============================================ */
#projects-section {
  background: var(--color-bg);
  padding: var(--section-padding) 0;
}

.field-card {
  background: var(--color-surface);
  border-left: 3px solid var(--color-accent);
  border-radius: 8px;
  padding: 32px;
  margin-bottom: 20px;
}

.field-label {
  font-size: 0.875rem;
  font-weight: 400;
  color: var(--color-accent);
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}

.field-catchphrase {
  font-size: 1.125rem;
  font-weight: 300;
  color: var(--color-text);
  margin-bottom: 16px;
}

.field-activities {
  font-size: 0.9375rem;
  font-weight: 300;
  color: var(--color-primary-light);
  line-height: 1.8;
}

.field-activities a {
  color: var(--color-primary-light);
}

.field-activities a:hover {
  color: var(--color-accent);
}

.field-activities .separator {
  color: var(--color-surface-dark);
  margin: 0 8px;
}


/* ============================================
   Section 7: Books (#books-section)
   ============================================ */
#books-section {
  background: var(--color-surface);
  padding: var(--section-padding) 0;
}

.books-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 24px;
}

.book-item {
  text-align: center;
}

.book-cover {
  aspect-ratio: 7 / 10;
  background: var(--color-surface-dark);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 12px;
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.book-cover:hover {
  transform: translateY(-4px);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.book-cover img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* Placeholder for missing cover images */
.book-cover--placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
  font-size: 0.75rem;
  color: var(--color-primary-light);
  line-height: 1.4;
}

.book-title {
  font-size: 0.8125rem;
  font-weight: 300;
  color: var(--color-text);
  line-height: 1.5;
}

@media (max-width: 1023px) {
  .books-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

@media (max-width: 768px) {
  .books-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }
}


/* ============================================
   Section 8: Contact (#contact-section)
   ============================================ */
#contact-section {
  background: var(--color-primary);
  /* When cta-bg.webp is available, uncomment:
  background:
    linear-gradient(180deg,
      rgba(26, 38, 57, 0.85) 0%,
      rgba(26, 38, 57, 0.9) 100%
    ),
    url('../images/cta-bg.webp') center/cover no-repeat;
  */
  padding: 160px 0;
  text-align: center;
}

.contact-message {
  font-size: 1.375rem;
  font-weight: 200;
  line-height: 2.0;
  color: var(--color-bg);
  margin-bottom: 0;
}

.contact-buttons {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

.cta-primary {
  display: inline-block;
  background: transparent;
  color: var(--color-accent);
  border: 1px solid var(--color-accent);
  padding: 16px 40px;
  font-family: var(--font-jp);
  font-size: 1rem;
  font-weight: 400;
  letter-spacing: 0.1em;
  text-decoration: none;
  transition: background var(--transition-base), color var(--transition-base);
  cursor: pointer;
  border-radius: 0;
  border-bottom: 1px solid var(--color-accent);
}

.cta-primary:hover {
  background: var(--color-accent);
  color: var(--color-bg);
  border-bottom-color: var(--color-accent);
}

.contact-sns {
  margin-top: 48px;
  font-size: 0.875rem;
  color: var(--color-text-light);
}

.contact-sns a {
  color: var(--color-text-light);
  border-bottom: none;
  transition: color var(--transition-base);
}

.contact-sns a:hover {
  color: var(--color-accent);
  border-bottom: none;
}

.contact-sns .separator {
  margin: 0 12px;
  opacity: 0.5;
}

@media (max-width: 768px) {
  #contact-section {
    padding: 120px 0;
  }

  .contact-message {
    font-size: 1.125rem;
  }

  .cta-primary {
    padding: 14px 32px;
    font-size: 0.9375rem;
    width: 80%;
    max-width: 320px;
  }
}


/* ============================================
   Footer
   ============================================ */
.site-footer {
  background: var(--color-surface-dark);
  padding: 80px 0 40px;
  text-align: center;
}

.footer-nav {
  font-size: 0.875rem;
  color: var(--color-primary-light);
}

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

.footer-nav .separator {
  margin: 0 12px;
  opacity: 0.5;
}

.footer-copyright {
  font-family: var(--font-en);
  font-size: 0.75rem;
  color: var(--color-primary-light);
  margin-top: 40px;
  letter-spacing: 0.05em;
}


/* ============================================
   CTA link (section bottom links)
   ============================================ */
.section-cta {
  text-align: center;
  margin-top: 48px;
}