/* ============================================================
   InfraSense — Design Tokens & Component Styles
   ============================================================ */

/* --- Fonts --- */
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@300;400;500;700&family=Inter:wght@300;400;500;600;700&display=swap');

:root {
  --font-body: 'Noto Sans JP', 'Inter', 'Helvetica Neue', sans-serif;
  --font-display: 'Inter', 'Noto Sans JP', 'Helvetica Neue', sans-serif;

  /* Type Scale */
  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.8rem  + 0.35vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw, 1.125rem);
  --text-lg:   clamp(1.125rem, 1rem    + 0.75vw, 1.5rem);
  --text-xl:   clamp(1.5rem,   1.2rem  + 1.25vw, 2.25rem);
  --text-2xl:  clamp(2rem,     1.2rem  + 2.5vw,  3.5rem);

  /* Spacing (4px base) */
  --space-1:  0.25rem;
  --space-2:  0.5rem;
  --space-3:  0.75rem;
  --space-4:  1rem;
  --space-5:  1.25rem;
  --space-6:  1.5rem;
  --space-8:  2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;

  /* Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-interactive: 180ms cubic-bezier(0.16, 1, 0.3, 1);

  /* Content widths */
  --content-narrow: 640px;
  --content-default: 960px;
  --content-wide: 1200px;
}

/* --- Light Mode (default) --- */
:root, [data-theme="light"] {
  --color-bg:             #f5f7f8;
  --color-surface:        #ffffff;
  --color-surface-2:      #f0f4f5;
  --color-surface-offset: #e8eef0;
  --color-divider:        #d5dde0;
  --color-border:         #c5cfd3;

  --color-text:           #1a2a30;
  --color-text-muted:     #5a6e78;
  --color-text-faint:     #9aabb5;
  --color-text-inverse:   #f5f7f8;

  /* Primary: derived from logo blue-cyan */
  --color-primary:        #2181b8;
  --color-primary-hover:  #1a6a9a;
  --color-primary-active: #155680;
  --color-primary-light:  #e6f2fa;
  --color-primary-highlight: #cde4f0;

  /* Gradient matching logo */
  --gradient-brand: linear-gradient(135deg, #2563a8 0%, #30a5c8 50%, #45c5d8 100%);

  --shadow-sm: 0 1px 2px rgba(26, 42, 48, 0.06);
  --shadow-md: 0 4px 12px rgba(26, 42, 48, 0.08);
  --shadow-lg: 0 12px 32px rgba(26, 42, 48, 0.12);
}

/* --- Dark Mode --- */
[data-theme="dark"] {
  --color-bg:             #0e1418;
  --color-surface:        #151c21;
  --color-surface-2:      #1a2329;
  --color-surface-offset: #1e272e;
  --color-divider:        #263038;
  --color-border:         #324048;

  --color-text:           #cdd8de;
  --color-text-muted:     #7a919c;
  --color-text-faint:     #4e6270;
  --color-text-inverse:   #151c21;

  --color-primary:        #4db0e0;
  --color-primary-hover:  #3a9dd0;
  --color-primary-active: #2a88b8;
  --color-primary-light:  #1a2e3a;
  --color-primary-highlight: #1e3545;

  --gradient-brand: linear-gradient(135deg, #3a8ad0 0%, #45b8d8 50%, #5cd0e8 100%);

  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.45);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) {
    --color-bg:             #0e1418;
    --color-surface:        #151c21;
    --color-surface-2:      #1a2329;
    --color-surface-offset: #1e272e;
    --color-divider:        #263038;
    --color-border:         #324048;
    --color-text:           #cdd8de;
    --color-text-muted:     #7a919c;
    --color-text-faint:     #4e6270;
    --color-text-inverse:   #151c21;
    --color-primary:        #4db0e0;
    --color-primary-hover:  #3a9dd0;
    --color-primary-active: #2a88b8;
    --color-primary-light:  #1a2e3a;
    --color-primary-highlight: #1e3545;
    --gradient-brand: linear-gradient(135deg, #3a8ad0 0%, #45b8d8 50%, #5cd0e8 100%);
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.25);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.35);
    --shadow-lg: 0 12px 32px rgba(0, 0, 0, 0.45);
  }
}

/* ============================================================
   GLOBAL LAYOUT
   ============================================================ */

.container {
  width: 100%;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

.container--narrow {
  max-width: var(--content-default);
}

/* ============================================================
   HEADER
   ============================================================ */

.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--color-bg) 88%, transparent);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid color-mix(in srgb, var(--color-border) 40%, transparent);
  transition: box-shadow 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

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

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: clamp(56px, 8vw, 72px);
}

.header__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
  color: var(--color-text);
}

.header__logo-img {
  height: 32px;
  width: 32px;
  object-fit: contain;
}

.header__logo-text {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.02em;
}

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

.header__nav a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
  font-weight: 500;
  letter-spacing: 0.01em;
  position: relative;
}

.header__nav a::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1.5px;
  background: var(--color-primary);
  transition: width var(--transition-interactive);
}

.header__nav a:hover {
  color: var(--color-text);
}

.header__nav a:hover::after {
  width: 100%;
}

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
}

.theme-toggle:hover {
  color: var(--color-text);
  background: var(--color-surface-2);
}

/* Mobile nav */
.mobile-menu-btn {
  display: none;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
}

.mobile-menu-btn:hover {
  color: var(--color-text);
}

@media (max-width: 768px) {
  .header__nav {
    display: none;
    position: fixed;
    top: clamp(56px, 8vw, 72px);
    left: 0;
    right: 0;
    bottom: 0;
    width: 100%;
    height: calc(100vh - clamp(56px, 8vw, 72px));
    height: calc(100dvh - clamp(56px, 8vw, 72px));
    background: var(--color-bg);
    flex-direction: column;
    align-items: flex-start;
    padding: var(--space-8) var(--space-6);
    gap: var(--space-4);
    border-top: 1px solid var(--color-divider);
    z-index: 49;
    overflow-y: auto;
  }

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

  .header__nav a {
    font-size: var(--text-base);
    padding: var(--space-2) 0;
  }

  .mobile-menu-btn {
    display: flex;
  }
}

/* ============================================================
   HERO
   ============================================================ */

.hero {
  padding-block: clamp(var(--space-16), 10vw, var(--space-32));
  position: relative;
  overflow: hidden;
}

.hero__content {
  position: relative;
  z-index: 2;
}

.hero__tagline-ja {
  font-family: var(--font-body);
  font-size: var(--text-2xl);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: 0.02em;
  color: var(--color-text);
  margin-bottom: var(--space-3);
}

.hero__tagline-en {
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 400;
  color: var(--color-text-muted);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: var(--space-8);
}

.hero__description {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  max-width: 600px;
  line-height: 1.9;
  margin-bottom: var(--space-4);
}

.hero__description + .hero__description {
  margin-top: var(--space-2);
  margin-bottom: 0;
}

/* Hero CTA group */
.hero__cta-group {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-top: var(--space-8);
  flex-wrap: wrap;
}

.hero__cta {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  font-weight: 500;
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-md);
  text-decoration: none;
  min-height: 44px;
}

.hero__cta svg {
  display: inline;
  width: 18px;
  height: 18px;
  flex-shrink: 0;
}

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

.hero__cta--primary:hover {
  background: var(--color-primary-hover);
}

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

.hero__cta--secondary:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
}



/* Decorative background */
.hero__bg {
  position: absolute;
  top: -15%;
  right: -8%;
  width: 55%;
  max-width: 480px;
  z-index: 1;
  pointer-events: none;
  color: var(--color-primary);
}

.hero__bg svg {
  width: 100%;
  height: auto;
}

/* ============================================================
   SECTIONS
   ============================================================ */

.section {
  padding-block: clamp(var(--space-12), 8vw, var(--space-24));
}

.section--alt {
  background: var(--color-surface-2);
}

.section__header {
  margin-bottom: clamp(var(--space-8), 4vw, var(--space-12));
}

.section__label {
  font-family: var(--font-display);
  font-size: var(--text-xs);
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-3);
}

.section__title {
  font-family: var(--font-body);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.01em;
}

.section__divider {
  width: 40px;
  height: 2px;
  background: var(--color-primary);
  margin-top: var(--space-4);
  border-radius: var(--radius-full);
}

/* ============================================================
   SERVICES
   ============================================================ */

.services-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
}

@media (min-width: 640px) {
  .services-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (min-width: 960px) {
  .services-grid {
    grid-template-columns: 1fr 1fr 1fr;
  }
}

.service-card {
  background: var(--color-surface);
  border: 1px solid color-mix(in srgb, var(--color-border) 50%, transparent);
  border-radius: var(--radius-lg);
  padding: var(--space-6) var(--space-6) var(--space-8);
  transition: box-shadow var(--transition-interactive),
              border-color var(--transition-interactive);
}

.service-card:hover {
  box-shadow: var(--shadow-md);
  border-color: color-mix(in srgb, var(--color-primary) 30%, transparent);
}

.service-card__icon {
  width: 40px;
  height: 40px;
  color: var(--color-primary);
  margin-bottom: var(--space-5);
}

.service-card__title {
  font-family: var(--font-body);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-3);
  letter-spacing: 0.01em;
}

.service-card__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.7;
}



/* ============================================================
   CTA BANNER (after services)
   ============================================================ */

.cta-banner {
  margin-top: clamp(var(--space-8), 4vw, var(--space-12));
  background: var(--color-surface);
  border: 1px solid color-mix(in srgb, var(--color-border) 50%, transparent);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
}

.cta-banner__items {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-6);
}

.cta-banner__item {
  display: flex;
  gap: var(--space-4);
  align-items: flex-start;
}

.cta-banner__icon {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  color: var(--color-primary);
  margin-top: 2px;
}

.cta-banner__title {
  font-size: var(--text-sm);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-1);
}

.cta-banner__text {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  line-height: 1.7;
}

.cta-banner__action {
  margin-top: var(--space-6);
  padding-top: var(--space-6);
  border-top: 1px solid color-mix(in srgb, var(--color-divider) 60%, transparent);
  text-align: center;
}

/* ============================================================
   COMPANY INFO
   ============================================================ */

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

.company-row {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: var(--space-4);
  padding: var(--space-4) 0;
  border-bottom: 1px solid color-mix(in srgb, var(--color-divider) 60%, transparent);
  align-items: baseline;
}

.company-row:last-child {
  border-bottom: none;
}

.company-row__label {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
  white-space: nowrap;
}

.company-row__value {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.7;
}

@media (max-width: 480px) {
  .company-row {
    grid-template-columns: 1fr;
    gap: var(--space-1);
  }
}

/* ============================================================
   CONTACT
   ============================================================ */

.contact-box {
  background: var(--color-surface);
  border: 1px solid color-mix(in srgb, var(--color-border) 50%, transparent);
  border-radius: var(--radius-lg);
  padding: var(--space-8);
  text-align: left;
  max-width: 640px;
}

.contact-box__text {
  font-size: var(--text-base);
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
  line-height: 1.8;
}

/* --- Contact Form --- */

.contact-form {
  display: flex;
  flex-direction: column;
  gap: var(--space-5);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.form-label {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text);
}

.form-required {
  color: #d04040;
  font-weight: 400;
}

.form-input {
  font-size: var(--text-sm);
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background: var(--color-bg);
  color: var(--color-text);
  width: 100%;
  outline: none;
  transition: border-color var(--transition-interactive),
              box-shadow var(--transition-interactive);
}

.form-input:focus {
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-primary) 15%, transparent);
}

.form-input::placeholder {
  color: var(--color-text-faint);
}

.form-input.is-invalid {
  border-color: #d04040;
}

.form-textarea {
  resize: vertical;
  min-height: 120px;
}

.form-submit {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-inverse);
  background: var(--color-primary);
  padding: var(--space-3) var(--space-8);
  border-radius: var(--radius-md);
  align-self: flex-start;
  min-height: 44px;
}

.form-submit:hover {
  background: var(--color-primary-hover);
}

.form-submit:active {
  background: var(--color-primary-active);
}

.form-submit:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.form-submit__loading svg {
  display: inline;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* Result state */
.form-result {
  text-align: center;
  padding: var(--space-8) 0;
}

.form-result__icon {
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}

.form-result__icon svg {
  display: inline;
  margin: 0 auto;
}

.form-result__title {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

.form-result__text {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  line-height: 1.8;
}

/* ============================================================
   FOOTER
   ============================================================ */

.footer {
  padding-block: var(--space-8);
  border-top: 1px solid var(--color-divider);
}

.footer__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--space-4);
}

.footer__logo {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--color-text-muted);
  text-decoration: none;
}

.footer__logo-img {
  height: 24px;
  width: 24px;
  object-fit: contain;
}

.footer__logo-text {
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
}

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

/* ============================================================
   SCROLL REVEAL
   ============================================================ */

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1),
              transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

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

@media (prefers-reduced-motion: reduce) {
  .reveal {
    opacity: 1;
    transform: none;
    transition: none;
  }
}