/* ============================================================
   Nuldom Studio Portfolio — style.css
   ============================================================ */

/* ------------------------------------------------------------
   1. CSS Custom Properties
   ------------------------------------------------------------ */
:root {
  /* Colors */
  --color-bg: #0E0E10;
  --color-bg-section: #16161A;
  --color-border: #26262C;
  --color-text: #E5E5E7;
  --color-text-sub: #8A8A92;
  --color-accent: #D9603B;
  --color-grey-cold: #52525B;

  /* Fonts */
  --font-mono: 'JetBrains Mono', monospace;
  --font-sans: 'Inter', sans-serif;
  --font-jp: 'Noto Sans JP', sans-serif;

  /* Spacing */
  --content-max-width: 1280px;
  --section-padding-pc: 140px;
  --section-padding-sp: 80px;
  --gap-sm: 8px;
  --gap-md: 24px;
  --gap-lg: 48px;

  /* Radius — terminal aesthetic, straight lines */
  --radius-none: 0px;
  --radius-sm: 4px;

  /* Letter spacing */
  --ls-label: 0.2em;
  --ls-nav: 0.12em;
  --ls-heading: 0.02em;

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

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

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

body {
  background-color: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-jp), var(--font-sans), sans-serif;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  min-height: 100vh;
}

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

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

ul,
ol {
  list-style: none;
}

button {
  background: none;
  border: none;
  cursor: pointer;
  font-family: inherit;
  color: inherit;
}

dialog {
  background: none;
  border: none;
  padding: 0;
  color: inherit;
}

/* ------------------------------------------------------------
   3. Utilities
   ------------------------------------------------------------ */
.content-wrap {
  max-width: var(--content-max-width);
  margin: 0 auto;
  padding: 0 var(--gap-lg);
}

.brand-name {
  font-family: var(--font-mono);
  font-weight: 500;
  letter-spacing: var(--ls-label);
  color: var(--color-text);
}

/* ------------------------------------------------------------
   4. Navigation
   ------------------------------------------------------------ */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
  padding: 0 var(--gap-lg);
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
}

.nav-brand .brand-name {
  font-size: 0.875rem;
  letter-spacing: var(--ls-label);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--gap-md);
}

.nav-links a {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: var(--ls-nav);
  color: var(--color-text-sub);
  transition: color var(--transition-base);
  padding: 4px 0;
  position: relative;
}

.nav-links a::before {
  content: '';
  position: absolute;
  left: -8px;
  top: 50%;
  transform: translateY(-50%);
  width: 2px;
  height: 0;
  background: var(--color-accent);
  transition: height var(--transition-base);
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--color-text);
}

.nav-links a.is-active::before {
  height: 14px;
}

/* Hamburger */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
  width: 32px;
  height: 32px;
  padding: 4px;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 1px;
  background: var(--color-text);
  transition: transform var(--transition-base), opacity var(--transition-base);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

/* ------------------------------------------------------------
   5. Terminal Frame
   ------------------------------------------------------------ */
.terminal-frame {
  margin-top: 56px; /* nav height */
}

.terminal-titlebar {
  display: none; /* shown on PC via media query */
}

/* ------------------------------------------------------------
   6. Section Base
   ------------------------------------------------------------ */
section {
  position: relative;
  padding: var(--section-padding-sp) 0;
  border-bottom: 1px solid var(--color-border);
}

section:nth-child(even) {
  background-color: var(--color-bg-section);
}

.view-label {
  position: absolute;
  top: var(--gap-md);
  left: var(--gap-lg);
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-text-sub);
  letter-spacing: var(--ls-label);
  opacity: 0.6;
  pointer-events: none;
  user-select: none;
}

.section-header {
  margin-bottom: var(--gap-lg);
}

.section-title {
  font-family: var(--font-mono);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 500;
  letter-spacing: var(--ls-heading);
  color: var(--color-text);
  margin-bottom: var(--gap-sm);
}

.section-sub {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-sub);
  letter-spacing: var(--ls-label);
  margin-bottom: var(--gap-sm);
}

.section-body {
  font-size: 0.9rem;
  color: var(--color-text-sub);
  line-height: 1.8;
}

/* ------------------------------------------------------------
   7. Hero Section
   ------------------------------------------------------------ */
#home {
  min-height: calc(100vh - 56px);
  display: flex;
  align-items: center;
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding-top: calc(var(--section-padding-sp) + 24px);
  padding-bottom: var(--section-padding-sp);
}

.hero-inner {
  display: flex;
  flex-direction: column;
  gap: var(--gap-lg);
  width: 100%;
}

.hero-main {
  flex: 1;
}

.hero-title {
  font-family: var(--font-mono);
  font-size: clamp(2rem, 6vw, 3.5rem);
  font-weight: 500;
  letter-spacing: var(--ls-heading);
  line-height: 1.2;
  margin-bottom: var(--gap-sm);
}

.hero-title-note {
  font-size: 0.5em;
  color: var(--color-text-sub);
  vertical-align: middle;
}

.hero-sub {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--color-accent);
  letter-spacing: var(--ls-label);
  margin-bottom: var(--gap-md);
}

.hero-body {
  font-size: 1.05rem;
  color: var(--color-text);
  margin-bottom: var(--gap-sm);
  line-height: 1.8;
}

.hero-note {
  font-size: 0.85rem;
  color: var(--color-text-sub);
  margin-bottom: var(--gap-lg);
  line-height: 1.8;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--gap-md);
}

/* Buttons */
.btn-primary,
.btn-secondary {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: var(--ls-label);
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  transition: background var(--transition-base), color var(--transition-base), border-color var(--transition-base);
}

.btn-primary {
  background: var(--color-accent);
  color: #fff;
  border: 1px solid var(--color-accent);
}

.btn-primary:hover {
  background: transparent;
  color: var(--color-accent);
}

.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  border-color: var(--color-text-sub);
  color: var(--color-text);
}

/* Hero Terminal */
.hero-terminal {
  flex: 1;
}

.hero-terminal-inner {
  border: 1px solid var(--color-border);
  background: var(--color-bg-section);
  padding: var(--gap-md);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1.9;
}

.terminal-line {
  display: block;
  color: var(--color-text-sub);
}

.terminal-line .prompt {
  color: var(--color-accent);
  margin-right: 8px;
  font-weight: 500;
}

.terminal-line.indent {
  padding-left: 20px;
  color: var(--color-text);
}

.terminal-line.mt {
  margin-top: 8px;
}

.cursor {
  display: inline-block;
  width: 8px;
  height: 1em;
  background: var(--color-text);
  vertical-align: middle;
  animation: blink 1.1s step-end infinite;
  font-size: 0;
  line-height: 0;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50%       { opacity: 0; }
}

/* ------------------------------------------------------------
   8. Works Section
   ------------------------------------------------------------ */
.works-filter {
  display: flex;
  flex-wrap: wrap;
  gap: var(--gap-sm);
  margin-bottom: var(--gap-lg);
}

.category-chip {
  border: 1px solid var(--color-border);
  border-radius: 100px;
  padding: 4px 14px;
  background: transparent;
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-text-sub);
  letter-spacing: var(--ls-label);
  transition: border-color var(--transition-base), color var(--transition-base), background var(--transition-base);
}

.category-chip:hover {
  border-color: var(--color-grey-cold);
  color: var(--color-text);
}

.category-chip.active {
  border-color: var(--color-text);
  color: var(--color-text);
  background: var(--color-border);
}

/* Works Grid */
.works-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap-md);
}

/* Work Card */
.work-card {
  border: 1px solid var(--color-border);
  background: var(--color-bg-section);
  border-radius: var(--radius-sm);
  overflow: hidden;
  cursor: pointer;
  transition: border-color var(--transition-base), transform var(--transition-base);
  display: flex;
  flex-direction: column;
}

.work-card:hover {
  border-color: var(--color-text-sub);
  transform: translateY(-2px);
}

.work-card:focus {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  padding: var(--gap-md) var(--gap-md) 0;
  gap: var(--gap-sm);
}

.card-number {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-accent);
  letter-spacing: var(--ls-label);
  flex-shrink: 0;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  justify-content: flex-end;
}

.card-tag {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--color-text-sub);
  letter-spacing: 0.05em;
}

.card-body {
  padding: 12px var(--gap-md) var(--gap-md);
  flex: 1;
}

.card-title {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: 8px;
  letter-spacing: var(--ls-heading);
}

.card-summary {
  font-size: 0.82rem;
  color: var(--color-text-sub);
  line-height: 1.7;
}

.card-preview {
  overflow: hidden;
  background: var(--color-bg);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  aspect-ratio: 16 / 9;
  position: relative;
}

.card-preview img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.work-card:hover .card-preview img {
  transform: scale(1.03);
}

/* Fallback when no image */
.card-preview-placeholder {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-grey-cold);
  letter-spacing: var(--ls-label);
  background: var(--color-bg);
}

.card-footer {
  padding: 12px var(--gap-md);
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

.card-action {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-accent);
  letter-spacing: var(--ls-label);
  transition: color var(--transition-base);
}

.work-card:hover .card-action {
  color: var(--color-text);
}

/* ------------------------------------------------------------
   9. Capabilities Section
   ------------------------------------------------------------ */
.capabilities-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap-md);
}

.capability-card {
  border: 1px solid var(--color-border);
  background: var(--color-bg-section);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: border-color var(--transition-base);
}

.capability-card:hover {
  border-color: var(--color-grey-cold);
}

.cap-top {
  padding: var(--gap-md);
}

.cap-number {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--color-accent);
  letter-spacing: var(--ls-label);
  margin-bottom: 8px;
}

.cap-labels {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 10px;
}

.cap-label {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-text);
  letter-spacing: var(--ls-heading);
}

.cap-label-jp {
  font-family: var(--font-jp);
  font-size: 0.78rem;
  color: var(--color-text-sub);
}

.cap-abstract {
  font-size: 0.82rem;
  color: var(--color-text-sub);
  line-height: 1.6;
}

.cap-bottom {
  padding: 10px var(--gap-md);
  background: #1E1E22;
  border-top: 1px solid var(--color-border);
  display: flex;
  align-items: center;
  gap: 10px;
}

.cap-application-label {
  font-family: var(--font-mono);
  font-size: 0.62rem;
  color: var(--color-grey-cold);
  letter-spacing: var(--ls-label);
  flex-shrink: 0;
}

.cap-application {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-text-sub);
  letter-spacing: 0.05em;
}

/* ------------------------------------------------------------
   10. Process Section
   ------------------------------------------------------------ */
.process-steps {
  display: flex;
  flex-direction: column;
  gap: 0;
  position: relative;
}

.process-steps::before {
  content: '';
  position: absolute;
  left: 22px;
  top: 0;
  bottom: 0;
  width: 1px;
  background: var(--color-border);
}

.process-step {
  display: flex;
  align-items: flex-start;
  gap: var(--gap-md);
  padding: var(--gap-md) 0;
  position: relative;
}

.step-number-wrap {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  background: var(--color-bg);
  border-radius: var(--radius-sm);
  position: relative;
  z-index: 1;
}

.step-number {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--color-accent);
  letter-spacing: 0.05em;
}

.step-content {
  flex: 1;
  padding-top: 10px;
}

.step-labels {
  display: flex;
  align-items: baseline;
  gap: 8px;
  margin-bottom: 4px;
}

.step-label {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--color-text);
  letter-spacing: var(--ls-heading);
}

.step-label-jp {
  font-family: var(--font-jp);
  font-size: 0.78rem;
  color: var(--color-text-sub);
}

.step-description {
  font-size: 0.82rem;
  color: var(--color-text-sub);
  line-height: 1.6;
}

/* ------------------------------------------------------------
   11. Quality Section
   ------------------------------------------------------------ */
.quality-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gap-md);
}

.quality-item {
  display: flex;
  gap: var(--gap-sm);
  align-items: flex-start;
  padding: var(--gap-md);
  border: 1px solid var(--color-border);
  background: var(--color-bg-section);
  border-radius: var(--radius-sm);
  transition: border-color var(--transition-base);
}

.quality-item:hover {
  border-color: var(--color-grey-cold);
}

.quality-prefix {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--color-accent);
  flex-shrink: 0;
  margin-top: 2px;
}

.quality-content {
  flex: 1;
}

.quality-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: 4px;
  letter-spacing: 0.04em;
}

.quality-description {
  font-size: 0.8rem;
  color: var(--color-text-sub);
  line-height: 1.6;
}

/* ------------------------------------------------------------
   12. Profile Section
   ------------------------------------------------------------ */
.profile-panel {
  max-width: 640px;
}

.profile-terminal {
  border: 1px solid var(--color-border);
  background: var(--color-bg-section);
  padding: var(--gap-md);
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.9;
}

.profile-terminal .terminal-line {
  display: block;
  color: var(--color-text-sub);
}

.profile-terminal .terminal-line .prompt {
  color: var(--color-accent);
  margin-right: 8px;
}

.profile-terminal .terminal-line.indent {
  padding-left: 16px;
  color: var(--color-text);
}

.profile-terminal .terminal-line.mt {
  margin-top: 10px;
}

/* ------------------------------------------------------------
   13. Contact Section
   ------------------------------------------------------------ */
.contact-panel {
  max-width: 640px;
  border: 1px solid var(--color-border);
  background: var(--color-bg-section);
  padding: var(--gap-lg) var(--gap-md);
  border-radius: var(--radius-sm);
}

.contact-body {
  font-size: 0.95rem;
  color: var(--color-text);
  margin-bottom: 12px;
  line-height: 1.8;
}

.contact-sub {
  font-size: 0.82rem;
  color: var(--color-text-sub);
  line-height: 1.7;
  margin-bottom: var(--gap-md);
}

.contact-form {
  display: grid;
  gap: 14px;
  margin-top: var(--gap-md);
}

.form-field {
  display: grid;
  gap: 6px;
}

.form-field span {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--color-text-sub);
  letter-spacing: var(--ls-label);
}

.form-field input,
.form-field textarea {
  width: 100%;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text);
  font: inherit;
  font-size: 0.9rem;
  line-height: 1.6;
  padding: 10px 12px;
  transition: border-color var(--transition-base), background var(--transition-base);
}

.form-field textarea {
  resize: vertical;
  min-height: 136px;
}

.form-field input:focus,
.form-field textarea:focus {
  outline: none;
  border-color: var(--color-accent);
  background: #111114;
}

.contact-submit {
  justify-self: start;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: #fff;
  letter-spacing: var(--ls-label);
  border: 1px solid var(--color-accent);
  background: var(--color-accent);
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  transition: background var(--transition-base), color var(--transition-base);
}

.contact-submit:hover,
.contact-submit:focus {
  background: transparent;
  color: var(--color-accent);
}

.form-status {
  min-height: 1.7em;
  font-size: 0.78rem;
  color: var(--color-text-sub);
  line-height: 1.7;
}

/* ------------------------------------------------------------
   14. Footer
   ------------------------------------------------------------ */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: var(--gap-lg) 0;
  background: var(--color-bg);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  text-align: center;
}

.footer-brand {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: var(--ls-label);
  color: var(--color-text-sub);
}

.footer-note {
  font-size: 0.72rem;
  color: var(--color-grey-cold);
}

.footer-copy {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-grey-cold);
  letter-spacing: 0.04em;
}

/* ------------------------------------------------------------
   15. Work Detail Dialog
   ------------------------------------------------------------ */
.work-detail-dialog {
  width: 100%;
  max-width: 100%;
  height: 100%;
  max-height: 100%;
  inset: 0;
  margin: 0;
  padding: 0;
  background: rgba(14, 14, 16, 0.96);
  border: none;
  overflow: hidden;
}

.work-detail-dialog[open] {
  display: flex;
  align-items: flex-start;
  justify-content: center;
}

.work-detail-dialog::backdrop {
  background: rgba(14, 14, 16, 0.8);
}

.dialog-inner {
  position: relative;
  width: 100%;
  max-width: 800px;
  max-height: 100vh;
  overflow-y: auto;
  background: var(--color-bg-section);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  margin: var(--gap-lg) var(--gap-md);
  padding: var(--gap-lg) var(--gap-md);
}

.dialog-close {
  position: sticky;
  top: 0;
  float: right;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-text-sub);
  letter-spacing: var(--ls-label);
  padding: 4px 8px;
  border: 1px solid var(--color-border);
  background: var(--color-bg-section);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color var(--transition-base), border-color var(--transition-base);
  z-index: 10;
  margin-bottom: var(--gap-md);
}

.dialog-close:hover {
  color: var(--color-text);
  border-color: var(--color-text-sub);
}

/* Dialog content */
.detail-header {
  margin-bottom: var(--gap-md);
  clear: both;
}

.detail-number {
  display: block;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--color-accent);
  letter-spacing: var(--ls-label);
  margin-bottom: 4px;
}

.detail-title {
  font-family: var(--font-mono);
  font-size: 1.4rem;
  font-weight: 500;
  color: var(--color-text);
  margin-bottom: 6px;
  letter-spacing: var(--ls-heading);
}

.detail-sub {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-text-sub);
  letter-spacing: 0.08em;
}

.detail-image {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  margin-bottom: var(--gap-lg);
  background: var(--color-bg);
}

.detail-image-placeholder {
  width: 100%;
  aspect-ratio: 16 / 9;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  margin-bottom: var(--gap-lg);
  background: var(--color-bg);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-grey-cold);
  letter-spacing: var(--ls-label);
}

.detail-dl {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 12px var(--gap-md);
  margin-bottom: var(--gap-lg);
  border: 1px solid var(--color-border);
  padding: var(--gap-md);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
}

.detail-dl dt {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--color-accent);
  letter-spacing: var(--ls-label);
  padding-top: 2px;
  white-space: nowrap;
}

.detail-dl dd {
  font-size: 0.85rem;
  color: var(--color-text);
  line-height: 1.7;
}

.detail-sample-link {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--color-accent);
  letter-spacing: var(--ls-label);
  border: 1px solid var(--color-accent);
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  transition: background var(--transition-base), color var(--transition-base);
}

.detail-sample-link:hover {
  background: var(--color-accent);
  color: #fff;
}

.detail-link-note {
  font-size: 0.78rem;
  color: var(--color-text-sub);
  line-height: 1.7;
}

/* ------------------------------------------------------------
   16. Scroll Animation
   ------------------------------------------------------------ */
.work-card,
.capability-card,
.process-step,
.quality-item {
  opacity: 0;
  transform: translateY(10px);
  transition: opacity var(--transition-slow), transform var(--transition-slow);
}

.work-card.is-visible,
.capability-card.is-visible,
.process-step.is-visible,
.quality-item.is-visible {
  opacity: 1;
  transform: none;
}

/* Stagger delay for grid items */
.work-card:nth-child(2)     { transition-delay: 0.08s; }
.work-card:nth-child(3)     { transition-delay: 0.16s; }

.capability-card:nth-child(2) { transition-delay: 0.06s; }
.capability-card:nth-child(3) { transition-delay: 0.12s; }
.capability-card:nth-child(4) { transition-delay: 0.18s; }
.capability-card:nth-child(5) { transition-delay: 0.06s; }
.capability-card:nth-child(6) { transition-delay: 0.12s; }

.process-step:nth-child(2)  { transition-delay: 0.06s; }
.process-step:nth-child(3)  { transition-delay: 0.12s; }
.process-step:nth-child(4)  { transition-delay: 0.18s; }
.process-step:nth-child(5)  { transition-delay: 0.24s; }
.process-step:nth-child(6)  { transition-delay: 0.30s; }

.quality-item:nth-child(2)  { transition-delay: 0.06s; }
.quality-item:nth-child(3)  { transition-delay: 0.06s; }
.quality-item:nth-child(4)  { transition-delay: 0.12s; }
.quality-item:nth-child(5)  { transition-delay: 0.12s; }
.quality-item:nth-child(6)  { transition-delay: 0.18s; }
.quality-item:nth-child(7)  { transition-delay: 0.18s; }

/* ------------------------------------------------------------
   17. Responsive — Tablet ≥ 640px
   ------------------------------------------------------------ */
@media (min-width: 640px) {
  .capabilities-grid {
    grid-template-columns: 1fr 1fr;
  }

  .quality-list {
    grid-template-columns: 1fr 1fr;
  }
}

/* ------------------------------------------------------------
   18. Responsive — PC ≥ 768px
   ------------------------------------------------------------ */
@media (min-width: 768px) {
  /* Nav */
  .nav-toggle {
    display: none;
  }

  .nav-links {
    display: flex !important; /* override mobile hidden state */
    position: static;
    flex-direction: row;
    background: none;
    border: none;
    padding: 0;
    width: auto;
  }

  /* Terminal frame */
  .terminal-frame {
    max-width: calc(var(--content-max-width) + 2px);
    margin: var(--gap-md) auto;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    overflow: hidden;
  }

  .terminal-titlebar {
    display: flex;
    align-items: center;
    gap: var(--gap-md);
    height: 36px;
    padding: 0 var(--gap-md);
    background: var(--color-bg-section);
    border-bottom: 1px solid var(--color-border);
    position: relative;
  }

  .terminal-dots {
    display: flex;
    gap: 6px;
    align-items: center;
    flex-shrink: 0;
  }

  .dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    display: block;
  }

  .dot-red    { background: #FF5F56; }
  .dot-yellow { background: #FFBD2E; }
  .dot-green  { background: #27C93F; }

  .terminal-title {
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    font-family: var(--font-mono);
    font-size: 0.72rem;
    color: var(--color-text-sub);
    letter-spacing: 0.08em;
    white-space: nowrap;
    pointer-events: none;
  }

  /* Sections */
  section {
    padding: var(--section-padding-pc) 0;
  }

  #home {
    padding-top: var(--section-padding-pc);
    padding-bottom: var(--section-padding-pc);
  }

  .content-wrap {
    padding: 0 var(--gap-lg);
  }

  /* Hero two-column */
  .hero-inner {
    flex-direction: row;
    align-items: center;
  }

  .hero-main {
    max-width: 52%;
  }

  .hero-terminal {
    max-width: 46%;
  }

  /* Works grid: 3 columns on PC */
  .works-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  /* Capabilities: 3 columns */
  .capabilities-grid {
    grid-template-columns: repeat(3, 1fr);
  }

  /* Process: horizontal */
  .process-steps {
    flex-direction: row;
    align-items: flex-start;
    gap: 0;
    overflow: visible;
  }

  .process-steps::before {
    top: 22px;
    left: 0;
    right: 0;
    bottom: auto;
    width: auto;
    height: 1px;
  }

  .process-step {
    flex: 1;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 0 var(--gap-sm);
  }

  .step-number-wrap {
    margin-bottom: var(--gap-sm);
    position: relative;
    z-index: 1;
    background: var(--color-bg);
  }

  .step-content {
    padding-top: 0;
  }

  .step-labels {
    flex-direction: column;
    align-items: center;
    gap: 2px;
  }

  /* Quality: 2 columns */
  .quality-list {
    grid-template-columns: 1fr 1fr;
  }

  /* Dialog */
  .dialog-inner {
    margin: var(--gap-lg) auto;
    padding: var(--gap-lg);
  }
}

/* ------------------------------------------------------------
   19. Mobile — nav overlay
   ------------------------------------------------------------ */
@media (max-width: 767px) {
  .nav-toggle {
    display: flex;
  }

  .nav-links {
    display: none;
    position: fixed;
    top: 56px;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--color-bg);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--gap-lg);
    border-top: 1px solid var(--color-border);
    z-index: 99;
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links a {
    font-size: 1rem;
    letter-spacing: var(--ls-nav);
  }

  .content-wrap {
    padding: 0 var(--gap-md);
  }

  .view-label {
    left: var(--gap-md);
  }

  .hero-inner {
    padding-top: var(--gap-md);
  }

  .detail-dl {
    grid-template-columns: 1fr;
    gap: var(--gap-md);
  }

  .detail-dl dt {
    margin-bottom: -8px;
  }

  .process-steps::before {
    left: 22px;
  }
}

/* ------------------------------------------------------------
   20. Reduced Motion
   ------------------------------------------------------------ */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }

  html {
    scroll-behavior: auto;
  }

  .work-card,
  .capability-card,
  .process-step,
  .quality-item {
    opacity: 1;
    transform: none;
  }
}