/* ============================================================
   Portfolio — styles.css
   Design System: Academic Mysticism / "The Arcane Editorial"
   ============================================================ */

/* --- Custom Properties --- */
:root {
  /* Core Palette */
  --color-surface:          #0c1420;   /* Prussian Blue — the void */
  --color-surface-low:      #141c28;   /* sections */
  --color-surface-high:     #232a37;   /* hovered cards / modals */
  --color-surface-highest:  #2c3544;   /* inputs */
  --color-surface-shadow:   #070e1a;   /* ambient shadow tint */

  --color-on-surface:       #dbe2f4;   /* Antique White — main text */
  --color-on-surface-sub:   #8a96b3;   /* secondary / meta text */

  --color-primary:          #f7bd48;   /* Aged Brass — CTA / highlight */
  --color-primary-hover:    #e5ac38;
  --color-primary-deep:     #ba880f;   /* container variant */
  --color-on-primary:       #0c1420;

  --color-outline-variant:  rgba(219, 226, 244, 0.15); /* ghost border */

  /* Typography */
  --font-serif:  "Newsreader", "Georgia", serif;
  --font-sans:   "Inter", "Hiragino Kaku Gothic ProN", "Noto Sans JP", sans-serif;

  /* Geometry */
  --radius-sm:   2px;
  --radius-md:   6px;
  --max-width:   960px;

  /* Transition */
  --transition: 0.25s ease;

  /* Spacing tokens */
  --spacing-4:  1.4rem;     /* between list items */
  --spacing-8:  2.75rem;    /* section gap */
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-serif);
  font-size:   1rem;
  line-height: 1.8;
  color:       var(--color-on-surface);
  background:  var(--color-surface);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='300' height='300' filter='url(%23n)' opacity='1'/%3E%3C/svg%3E");
  opacity: 0.035;
  pointer-events: none;
  z-index: 9999;
}

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

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

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

/* --- Focus --- */
:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* --- Container --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 32px;
}

/* ============================================================
   Under Construction Banner
   ============================================================ */
.under-construction-banner {
  position: sticky;
  top: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 24px;
  background:    rgba(35, 42, 55, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-outline-variant);
  font-family: var(--font-sans);
  font-size:   0.82rem;
  line-height: 1.6;
}

.uc-icon {
  font-size:   1.3rem;
  flex-shrink: 0;
}

.uc-text {
  display:        flex;
  flex-direction: column;
  gap: 2px;
}

.uc-en {
  color:       var(--color-on-surface);
  font-weight: 500;
}

.uc-ja {
  color: var(--color-on-surface-sub);
}

.uc-en a,
.uc-ja a {
  color:           var(--color-primary);
  text-decoration: underline;
  font-weight:     600;
}

.uc-en a:hover,
.uc-ja a:hover {
  color: var(--color-primary-hover);
}

.uc-close {
  margin-left: auto;
  flex-shrink: 0;
  background: transparent;
  border: none;
  color: var(--color-on-surface-sub);
  font-size: 1rem;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  transition: color var(--transition);
}

.uc-close:hover {
  color: var(--color-on-surface);
}

@media (max-width: 767px) {
  .under-construction-banner {
    padding:   10px 16px;
    font-size: 0.78rem;
  }
}

/* --- Skip Link --- */
.skip-link {
  position:    absolute;
  top:         -100%;
  left:        16px;
  background:  var(--color-primary);
  color:       var(--color-on-primary);
  padding:     8px 16px;
  border-radius: var(--radius-md);
  font-family: var(--font-sans);
  font-weight: 600;
  z-index:     1000;
  transition:  top var(--transition);
}

.skip-link:focus {
  top:   16px;
  color: var(--color-on-primary);
}

/* ============================================================
   Header / Nav
   ============================================================ */
.site-header {
  position:  fixed;
  top:       0;
  left:      0;
  right:     0;
  z-index:   100;
  /* Glassmorphism nav */
  background: rgba(12, 20, 32, 0.6);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-outline-variant);
}

.header-inner {
  max-width: var(--max-width);
  margin:    0 auto;
  padding:   0 32px;
  height:    64px;
  display:   flex;
  align-items:     center;
  justify-content: space-between;
}

.site-logo {
  font-family:    var(--font-serif);
  font-size:      1.1rem;
  font-weight:    700;
  font-style:     italic;
  color:          var(--color-on-surface);
  letter-spacing: -0.01em;
  transition:     color var(--transition);
}

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

/* --- Desktop Nav --- */
.nav-desktop .nav-list {
  display:     flex;
  gap:         32px;
  list-style:  none;
}

.nav-desktop .nav-list a {
  font-family:    var(--font-sans);
  color:          var(--color-on-surface-sub);
  font-size:      0.78rem;
  font-weight:    500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transition:     color var(--transition);
}

.nav-desktop .nav-list a:hover,
.nav-desktop .nav-list a[aria-current="true"] {
  color: var(--color-primary);
}

/* --- Mobile Nav --- */
.nav-mobile {
  display:  none;
  position: relative;
}

.nav-mobile summary {
  list-style: none;
  cursor:     pointer;
  padding:    8px;
  display:    flex;
  align-items: center;
}

.nav-mobile summary::-webkit-details-marker {
  display: none;
}

.hamburger-icon {
  display:        flex;
  flex-direction: column;
  gap:    5px;
  width:  22px;
}

.hamburger-icon span {
  display:       block;
  height:        2px;
  width:         100%;
  background:    var(--color-on-surface);
  border-radius: 2px;
  transition:    transform var(--transition), opacity var(--transition);
}

.nav-mobile[open] .hamburger-icon span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-mobile[open] .hamburger-icon span:nth-child(2) {
  opacity: 0;
}

.nav-mobile[open] .hamburger-icon span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.nav-list-mobile {
  list-style:   none;
  position:     absolute;
  top:          calc(100% + 12px);
  right:        0;
  background:   rgba(20, 28, 40, 0.95);
  backdrop-filter: blur(12px);
  border:       1px solid var(--color-outline-variant);
  border-radius: var(--radius-md);
  padding:      12px 0;
  min-width:    200px;
  box-shadow:   0 8px 32px rgba(7, 14, 26, 0.5);
}

.nav-list-mobile li a {
  display:        block;
  padding:        10px 24px;
  font-family:    var(--font-sans);
  color:          var(--color-on-surface-sub);
  font-weight:    500;
  font-size:      0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transition:     color var(--transition), background var(--transition);
}

.nav-list-mobile li a:hover {
  color:      var(--color-primary);
  background: rgba(247, 189, 72, 0.06);
}

/* ============================================================
   Hero
   ============================================================ */
.hero-section {
  position:        relative;
  min-height:      100vh;
  display:         flex;
  align-items:     center;
  justify-content: center;
  text-align:      center;
  padding:         140px 32px 100px;
  /* Subtle radial glow from center */
  background: radial-gradient(ellipse 80% 60% at 50% 40%,
      rgba(247, 189, 72, 0.06) 0%,
      var(--color-surface) 70%);
}

.hero-content {
  position: relative;
  z-index:  1;
}

.hero-avatar {
  width:         130px;
  height:        130px;
  margin:        0 auto 32px;
  border-radius: 50%;
  overflow:      hidden;
  /* Ghost border instead of solid */
  border:        1px solid var(--color-outline-variant);
  background:    var(--color-surface-low);
  box-shadow:    0 0 32px rgba(7, 14, 26, 0.5);
}

.hero-avatar svg,
.hero-avatar img {
  width:      100%;
  height:     100%;
  object-fit: cover;
}

.hero-name {
  font-family:    var(--font-serif);
  font-size:      clamp(2.2rem, 5vw, 3.5rem);
  font-weight:    700;
  font-style:     italic;
  letter-spacing: -0.02em;
  color:          var(--color-on-surface);
  margin-bottom:  8px;
  line-height:    1.2;
}

.hero-title {
  font-family: var(--font-sans);
  font-size:   0.78rem;
  color:       var(--color-primary);
  margin-bottom: 12px;
  font-weight:   500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.hero-tagline {
  font-family:   var(--font-serif);
  font-size:     1.05rem;
  font-style:    italic;
  color:         var(--color-on-surface-sub);
  max-width:     480px;
  margin:        0 auto 40px;
}

.hero-links {
  display:         flex;
  gap:             12px;
  justify-content: center;
  flex-wrap:       wrap;
}

/* Buttons — "Brass" Standard */
.hero-link-btn {
  display:     inline-flex;
  align-items: center;
  gap:         6px;
  padding:     9px 20px;
  /* Ghost / secondary style */
  border:        1px solid rgba(247, 189, 72, 0.25);
  border-radius: var(--radius-sm);
  color:         var(--color-primary);
  font-family:   var(--font-sans);
  font-size:     0.75rem;
  font-weight:   500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  background:    transparent;
  transition:    border-color var(--transition), color var(--transition),
                 background var(--transition), box-shadow var(--transition);
}

.hero-link-btn:hover {
  color:        var(--color-on-primary);
  background:   linear-gradient(135deg, var(--color-primary), var(--color-primary-deep));
  border-color: var(--color-primary);
  box-shadow:   0 0 20px rgba(247, 189, 72, 0.2);
}

/* ============================================================
   Section Common
   ============================================================ */
.section {
  padding: 96px 0;
}

/* Tonal section alternation — no lines */
.section-alt {
  background: var(--color-surface-low);
}

/* "Manuscript Header" — Japanese label above English heading */
.section-heading {
  font-family:    var(--font-serif);
  font-size:      clamp(1.5rem, 3vw, 1.75rem);
  font-weight:    700;
  font-style:     italic;
  letter-spacing: -0.02em;
  text-align:     left;
  color:          var(--color-on-surface);
  margin-bottom:  var(--spacing-8);
  /* Intentional asymmetry — left-aligned heading */
  padding-left:   0;
}

/* Japanese "stamp" label above heading */
.section-heading::before {
  content:        attr(data-ja);
  display:        block;
  font-family:    var(--font-sans);
  font-style:     normal;
  font-size:      0.7rem;
  font-weight:    500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color:          var(--color-primary);
  margin-bottom:  0.5rem;
}

/* ============================================================
   About
   ============================================================ */
.about-catch {
  font-family:    var(--font-serif);
  font-style:     italic;
  font-size:      1.1rem;
  font-weight:    400;
  color:          var(--color-primary);
  margin-bottom:  var(--spacing-4);
  letter-spacing: 0.01em;
}

.about-content {
  max-width:    680px;
  margin:       0 0 var(--spacing-4);
}

.about-content p {
  color:         var(--color-on-surface-sub);
  margin-bottom: 16px;
  text-align:    justify;
}

.skill-tags {
  display:   flex;
  flex-wrap: wrap;
  gap:       8px;
}

.tag {
  display:    inline-block;
  padding:    5px 14px;
  background: rgba(247, 189, 72, 0.08);
  color:      var(--color-primary);
  border:     1px solid rgba(247, 189, 72, 0.2);
  border-radius: var(--radius-sm);
  font-family:   var(--font-sans);
  font-size:     0.72rem;
  font-weight:   600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ============================================================
   Works
   ============================================================ */
.works-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--spacing-4);
}

.work-card {
  background:    var(--color-surface-high);
  border-radius: var(--radius-md);
  padding:       28px;
  /* Ambient shadow — no border */
  box-shadow:    0 0 32px rgba(7, 14, 26, 0.08);
  transition:    background var(--transition), box-shadow var(--transition);
}

.work-card:hover {
  background:  var(--color-surface-highest);
  box-shadow:  0 4px 32px rgba(7, 14, 26, 0.3);
}

.work-card h3 {
  font-family:   var(--font-serif);
  font-size:     1.05rem;
  font-weight:   700;
  font-style:    italic;
  margin-bottom: 10px;
  color:         var(--color-on-surface);
  line-height:   1.5;
}

.work-card p {
  font-family:   var(--font-sans);
  color:         var(--color-on-surface-sub);
  font-size:     0.88rem;
  margin-bottom: var(--spacing-4);
  line-height:   1.7;
}

.work-tags {
  display:       flex;
  flex-wrap:     wrap;
  gap:           6px;
  margin-bottom: 16px;
}

.work-tags .tag {
  font-size: 0.68rem;
  padding:   3px 10px;
}

.work-card .card-link {
  font-family:    var(--font-sans);
  font-size:      0.75rem;
  font-weight:    600;
  color:          var(--color-primary);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition:     color var(--transition);
}

.work-card .card-link::after {
  content: " →";
}

/* ============================================================
   Publications
   ============================================================ */
.publications-intro {
  color:       var(--color-on-surface-sub);
  margin-bottom: var(--spacing-4);
  max-width:   500px;
  font-family: var(--font-sans);
  font-size:   0.9rem;
}

.pub-links {
  display:   flex;
  flex-wrap: wrap;
  gap:       var(--spacing-4);
  margin:    0;
}

.pub-link-card {
  display:        flex;
  flex-direction: column;
  align-items:    flex-start;
  gap:            10px;
  padding:        32px 24px;
  flex:           1 1 200px;
  max-width:      280px;
  background:     var(--color-surface-high);
  border-radius:  var(--radius-md);
  color:          var(--color-on-surface);
  box-shadow:     0 0 32px rgba(7, 14, 26, 0.08);
  transition:     background var(--transition), box-shadow var(--transition);
}

.pub-link-card:hover {
  background:  var(--color-surface-highest);
  box-shadow:  0 4px 32px rgba(7, 14, 26, 0.3);
  color:       var(--color-primary);
}

.pub-link-card svg {
  color: var(--color-primary);
}

.pub-link-name {
  font-family: var(--font-serif);
  font-weight: 700;
  font-style:  italic;
  font-size:   1rem;
}

.pub-link-status {
  font-family:   var(--font-sans);
  font-size:     0.72rem;
  color:         var(--color-on-surface-sub);
  background:    var(--color-surface-low);
  padding:       2px 10px;
  border-radius: var(--radius-sm);
  letter-spacing: 0.04em;
}

/* ============================================================
   Presentations
   ============================================================ */
.presentations-list {
  list-style: none;
  max-width:  720px;
  display:    flex;
  flex-direction: column;
  gap: var(--spacing-4);
}

/* No divider lines — tonal stacking only */
.presentation-item {
  display:      flex;
  gap:          20px;
  align-items:  flex-start;
  background:   var(--color-surface-high);
  border-radius: var(--radius-md);
  padding:      24px;
  box-shadow:   0 0 32px rgba(7, 14, 26, 0.08);
  transition:   background var(--transition), box-shadow var(--transition);
}

.presentation-item:hover {
  background:  var(--color-surface-highest);
  box-shadow:  0 4px 32px rgba(7, 14, 26, 0.3);
}

.presentation-date {
  flex-shrink: 0;
  font-family: var(--font-sans);
  font-size:   0.72rem;
  font-weight: 700;
  color:       var(--color-primary);
  background:  rgba(247, 189, 72, 0.08);
  border:      1px solid rgba(247, 189, 72, 0.2);
  border-radius: var(--radius-sm);
  padding:     4px 12px;
  line-height: 1.6;
  letter-spacing: 0.04em;
}

.presentation-body {
  flex:      1;
  min-width: 0;
}

.presentation-title {
  font-family:   var(--font-serif);
  font-size:     0.95rem;
  font-weight:   700;
  font-style:    italic;
  color:         var(--color-on-surface);
  line-height:   1.6;
  margin-bottom: 6px;
}

.presentation-conference {
  font-family:   var(--font-sans);
  font-size:     0.82rem;
  color:         var(--color-on-surface-sub);
  line-height:   1.6;
  margin-bottom: 10px;
}

.presentation-type {
  font-size: 0.68rem;
  padding:   3px 10px;
}

/* --- Award Badge --- */
.award-badge {
  display:       inline-block;
  font-family:   var(--font-sans);
  color:         var(--color-primary);
  font-weight:   800;
  font-size:     0.82rem;
  margin-top:    6px;
  padding:       4px 14px;
  background:    rgba(247, 189, 72, 0.1);
  border:        1px solid rgba(247, 189, 72, 0.3);
  border-radius: var(--radius-sm);
  letter-spacing: 0.04em;
  animation:     award-pulse 2s ease-in-out infinite;
}

@keyframes award-pulse {
  0%,  100% { box-shadow: 0 0 6px rgba(247, 189, 72, 0.25); }
  50%        { box-shadow: 0 0 20px rgba(247, 189, 72, 0.6); }
}

/* ============================================================
   Certifications
   ============================================================ */
.certifications-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap:       var(--spacing-4);
  max-width: 720px;
}

.cert-card {
  display:      flex;
  align-items:  center;
  gap:          20px;
  background:   var(--color-surface-high);
  border-radius: var(--radius-md);
  padding:      24px;
  box-shadow:   0 0 32px rgba(7, 14, 26, 0.08);
  transition:   background var(--transition), box-shadow var(--transition);
}

.cert-card:hover {
  background:  var(--color-surface-highest);
  box-shadow:  0 4px 32px rgba(7, 14, 26, 0.3);
}

.cert-badge-img {
  width:         80px;
  height:        80px;
  flex-shrink:   0;
  border-radius: var(--radius-md);
  object-fit:    contain;
  background:    var(--color-surface-low);
}

.cert-info {
  flex:      1;
  min-width: 0;
}

.cert-name {
  font-family:   var(--font-serif);
  font-size:     0.95rem;
  font-weight:   700;
  font-style:    italic;
  color:         var(--color-on-surface);
  line-height:   1.5;
  margin-bottom: 4px;
}

.cert-issuer {
  font-family:   var(--font-sans);
  font-size:     0.78rem;
  color:         var(--color-on-surface-sub);
  margin-bottom: 4px;
}

.cert-date {
  font-family:   var(--font-sans);
  font-size:     0.72rem;
  color:         var(--color-primary);
  font-weight:   600;
  letter-spacing: 0.04em;
}

/* ============================================================
   Contact
   ============================================================ */
.contact-text {
  color:         var(--color-on-surface-sub);
  font-family:   var(--font-sans);
  max-width:     480px;
  margin:        0 0 32px;
}

/* Primary CTA — Brass Standard */
.btn {
  display:        inline-block;
  padding:        13px 36px;
  border-radius:  var(--radius-sm);
  font-family:    var(--font-sans);
  font-weight:    600;
  font-size:      0.85rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-align:     center;
  cursor:         pointer;
  border:         none;
  transition:     background var(--transition), box-shadow var(--transition),
                  transform var(--transition);
}

.btn:hover {
  box-shadow: 0 6px 24px rgba(247, 189, 72, 0.25);
}

/* Brass gradient */
.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-deep));
  color:      var(--color-on-primary);
}

.btn-primary:hover {
  background: linear-gradient(135deg, var(--color-primary-hover), var(--color-primary-deep));
  color:      var(--color-on-primary);
}

#contact .container {
  text-align: left;
}

/* ============================================================
   Footer
   ============================================================ */
.site-footer {
  padding:    40px 0;
  background: var(--color-surface-low);
  /* No border — tonal shift separates it */
}

.footer-links {
  display:         flex;
  gap:             20px;
  justify-content: flex-start;
  margin-bottom:   16px;
}

.footer-links a {
  color:      var(--color-on-surface-sub);
  transition: color var(--transition), transform var(--transition);
}

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

.footer-copy {
  font-family:    var(--font-sans);
  color:          var(--color-on-surface-sub);
  font-size:      0.78rem;
  letter-spacing: 0.04em;
}

/* ============================================================
   Subsection Heading
   ============================================================ */
.subsection-heading {
  font-family:    var(--font-serif);
  font-size:      1.1rem;
  font-weight:    700;
  font-style:     italic;
  color:          var(--color-on-surface);
  margin-top:     var(--spacing-8);
  margin-bottom:  28px;
  letter-spacing: -0.01em;
}

/* ============================================================
   Bilingual — Japanese 90% size rule (DESIGN.md §3)
   ============================================================ */
.ja {
  font-size: 0.9em;
}

/* ============================================================
   Scroll Reveal (JS adds .is-visible)
   ============================================================ */
.reveal {
  opacity:   0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

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

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 767px) {
  .nav-desktop { display: none; }
  .nav-mobile  { display: block; }

  .hero-section {
    min-height: auto;
    padding:    140px 24px 80px;
  }

  .hero-avatar {
    width:  100px;
    height: 100px;
  }

  .section { padding: 64px 0; }

  .works-grid { grid-template-columns: 1fr; }
  .pub-links  { flex-direction: column; }

  .hero-links {
    flex-direction: column;
    align-items:    center;
  }

  .section-heading { text-align: left; }

  .contact-text { max-width: 100%; }
}

@media (min-width: 768px) and (max-width: 1023px) {
  .works-grid { grid-template-columns: repeat(2, 1fr); }
}

/* ============================================================
   prefers-reduced-motion
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }

  *,
  *::before,
  *::after {
    transition-duration:       0.01ms !important;
    animation-duration:        0.01ms !important;
    animation-iteration-count: 1 !important;
  }

  .reveal { opacity: 1; transform: none; }

  .work-card:hover,
  .pub-link-card:hover,
  .cert-card:hover,
  .presentation-item:hover {
    transform:  none;
    box-shadow: none;
  }

  .btn:hover        { transform: none; }
  .footer-links a:hover { transform: none; }
  .hero-link-btn:hover  { box-shadow: none; }
}