:root {
    --bg-color: #FAFAFA;
    --text-color: #111111;
    --accent-color: #1A2B3C;
    --font-main: 'Zen Maru Gothic', sans-serif;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-main);
    font-weight: 400;
    line-height: 1.8;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6, .logo {
    font-family: var(--font-main);
    font-weight: 500;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 40px;
}

/* Header */
.header {
    position: fixed;
    top: var(--release-banner-height, 0px);
    width: 100%;
    z-index: 100;
    padding: 30px 0;
    transition: all 0.4s ease;
}

.header.scrolled,
.header.always-light {
    padding: 15px 0;
    background: rgba(250, 250, 250, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.05);
}
.header.always-light .logo,
.header.always-light .nav a {
    color: var(--text-color);
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
}

.logo {
    display: flex;
    align-items: flex-start;
    color: #fff;
    transition: color 0.4s ease;
    line-height: 1.2;
}

.logo-group {
    display: flex;
    flex-direction: column;
    align-items: center; /* Center perfectly beneath Y.A.Design */
}

.logo-main {
    font-size: 1.2rem;
    letter-spacing: 0.05em;
    font-weight: 500;
}

.logo-sub {
    font-size: 0.7rem;
    letter-spacing: 0.05em;
    opacity: 0.8;
    margin-top: 2px;
}

.logo-suffix {
    font-size: 1.2rem;
    font-weight: 500;
}

.header.scrolled .logo,
.header.scrolled .nav a {
    color: var(--text-color);
}

.nav ul {
    display: flex;
    list-style: none;
    gap: 40px;
    align-items: center;
}

.nav a {
    color: #fff;
    font-size: 0.9rem;
    letter-spacing: 0.05em;
    transition: opacity 0.3s;
}

.nav a:hover {
    opacity: 0.6;
}

.btn-contact {
    border: 1px solid currentColor;
    padding: 8px 24px;
    border-radius: 40px;
}

/* Hero */
.hero {
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    /* User's local file from artifact (Modern glass) */
    background-image: url('images/hero.png');
    background-size: cover;
    background-position: center;
    color: #fff;
}

.hero::after {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0, 0, 0, 0.3);
}

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

.hero-title {
    font-size: 2rem;
    letter-spacing: 0.04em;
    margin-bottom: 20px;
    text-shadow: 0 4px 12px rgba(0,0,0,0.3);
    line-height: 1.45;
    padding: 0 20px;
}

.hero-tagline {
    font-size: 1.4rem;
    letter-spacing: 0.15em;
    font-weight: 400;
    margin: 0 0 16px;
    opacity: 0.92;
}

.hero-subtitle {
    font-size: 1.2rem;
    letter-spacing: 0.2em;
    font-weight: 300;
}

.scroll-indicator {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1;
    font-size: 0.8rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

.scroll-indicator::after {
    content: '';
    width: 1px;
    height: 60px;
    background: #fff;
    animation: scrollLine 2s infinite cubic-bezier(0.645, 0.045, 0.355, 1);
}

@keyframes scrollLine {
    0% { transform: scaleY(0); transform-origin: top; }
    50% { transform: scaleY(1); transform-origin: top; }
    50.1% { transform: scaleY(1); transform-origin: bottom; }
    100% { transform: scaleY(0); transform-origin: bottom; }
}

/* Sections */
.section {
    padding: 150px 0;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 80px;
    letter-spacing: 0.1em;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 40px;
    height: 1px;
    background-color: var(--text-color);
    margin: 20px auto 0;
}

/* Concept */
.concept-text {
    text-align: center;
    font-size: 1.4rem;
    line-height: 2.5;
    letter-spacing: 0.1em;
}

/* Technology */
.tech-container {
    display: flex;
    align-items: center;
    gap: 80px;
}

.tech-text {
    flex: 1;
}

.tech-text .section-title {
    text-align: left;
}

.tech-text .section-title::after {
    margin: 20px 0 0;
}

.tech-subtitle {
    font-size: 1.6rem;
    margin-bottom: 30px;
}

.tech-visual {
    flex: 1.2;
}

.comparison-mockup {
    width: 100%;
    height: 500px;
    background: linear-gradient(135deg, #e0e0e0 0%, #f5f5f5 100%);
    position: relative;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    box-shadow: 0 20px 40px rgba(0,0,0,0.08);
    cursor: pointer;
    transition: transform 0.35s ease, box-shadow 0.35s ease;
}

.comparison-mockup:hover,
.comparison-mockup:focus-visible {
    transform: translateY(-4px);
    box-shadow: 0 28px 56px rgba(0,0,0,0.14);
    outline: none;
}

.mockup-label {
    font-weight: 500;
    color: var(--accent-color);
    letter-spacing: 0.1em;
}

.mockup-badge {
    position: absolute;
    top: 22px;
    left: 22px;
    padding: 5px 12px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.92);
    color: var(--accent-color);
    font-size: 0.72rem;
    font-weight: 500;
    letter-spacing: 0.08em;
    box-shadow: 0 2px 6px rgba(0,0,0,0.08);
    backdrop-filter: blur(2px);
    -webkit-backdrop-filter: blur(2px);
}

.mockup-play-icon {
    position: absolute;
    bottom: 28px;
    right: 28px;
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: rgba(0,0,0,0.72);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    padding-left: 6px;
    transition: background 0.3s ease, transform 0.3s ease;
}

.comparison-mockup:hover .mockup-play-icon,
.comparison-mockup:focus-visible .mockup-play-icon {
    background: rgba(0,0,0,0.92);
    transform: scale(1.08);
}

/* Video Modal */
.video-modal {
    position: fixed;
    inset: 0;
    z-index: 9999;
    display: none;
    align-items: center;
    justify-content: center;
    padding: 5vh 4vw;
}

.video-modal.active {
    display: flex;
}

.video-modal-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.86);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    cursor: pointer;
}

.video-modal-content {
    position: relative;
    max-width: min(92vw, 1280px);
    width: 100%;
}

.video-modal-content video {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 4px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.55);
}

.video-modal-close {
    position: absolute;
    top: -44px;
    right: 0;
    background: none;
    border: none;
    color: #fff;
    font-size: 2.2rem;
    line-height: 1;
    cursor: pointer;
    padding: 4px 12px;
    font-family: inherit;
}

.video-modal-close:hover {
    opacity: 0.7;
}

/* Features (取扱説明書レベルの詳細カード) */
.features-section {
    background: #FAFAFA;
}
.features-section .section-lead {
    display: block;
    text-align: center;
    font-size: 1.6rem;
    font-weight: 500;
    color: #2A2A2A;
    margin: 24px auto 56px;
    line-height: 1.6;
    letter-spacing: 0.02em;
    width: 100%;
}
.features-list {
    display: flex;
    flex-direction: column;
    gap: 48px;
    max-width: 900px;
    margin: 0 auto;
}
.feature-card {
    position: relative;
    background: #fff;
    border: 1px solid #ECECEC;
    border-radius: 4px;
    padding: 56px 48px 48px;
    box-shadow: 0 2px 16px rgba(0, 0, 0, 0.03);
}
.feature-num {
    position: absolute;
    top: 24px;
    right: 32px;
    font-size: 2.4rem;
    font-weight: 300;
    color: #DCDCDC;
    letter-spacing: 0.05em;
    font-family: 'Outfit', 'Inter', sans-serif;
}
.feature-title {
    font-size: clamp(1.4rem, 2.2vw, 1.7rem);
    font-weight: 500;
    color: #2A2A2A;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid #ECECEC;
}
.feature-desc {
    font-size: 0.95rem;
    line-height: 2;
    color: #1F1F1F;
    margin-bottom: 32px;
}
.feature-image {
    width: 100%;
    margin: 0 0 32px;
    border-radius: 4px;
    overflow: hidden;
    background: #F4F4F4;
    border: 1px solid #ECECEC;
}
.feature-image img {
    display: block;
    width: 100%;
    height: auto;
}
.feature-items {
    list-style: none;
    padding: 0;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.feature-items li {
    position: relative;
    padding-left: 22px;
    font-size: 0.9rem;
    line-height: 1.85;
    color: #2A2A2A;
}
.feature-items li::before {
    content: '';
    position: absolute;
    left: 4px;
    top: 14px;
    width: 8px;
    height: 1px;
    background: #888;
}
.feature-items li strong {
    color: #1A2B3C;
    font-weight: 600;
}
@media (max-width: 768px) {
    .feature-card {
        padding: 40px 24px 32px;
    }
    .feature-num {
        font-size: 1.8rem;
        top: 16px;
        right: 20px;
    }
    .feature-title {
        font-size: 1.25rem;
    }
}

/* About */
.about-content {
    display: flex;
    gap: 80px;
    align-items: center;
}

.about-profile {
    flex: 1;
}

.profile-name {
    font-weight: 700;
    font-size: 1.4rem;
    margin-bottom: 30px;
    color: var(--accent-color);
}

.profile-credentials, .profile-history {
    font-size: 0.9rem;
    line-height: 1.8;
    margin-bottom: 30px;
    color: #1F1F1F;
}

.profile-greeting-title {
    font-weight: 700;
    font-size: 1.2rem;
    margin-bottom: 15px;
    margin-top: 40px;
}

.profile-text {
    line-height: 2;
    color: #1F1F1F;
    font-size: 0.95rem;
}

.company-info {
    flex: 1;
    background: #fff;
    padding: 40px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.04);
    border-radius: 4px;
}

.company-info dl {
    display: flex;
    flex-wrap: wrap;
    row-gap: 20px;
    font-size: 0.95rem;
}

.company-info dt {
    width: 30%;
    font-weight: 500;
    color: var(--accent-color);
}

.company-info dd {
    width: 70%;
    color: #1F1F1F;
}

/* Footer */
.footer {
    text-align: center;
    padding: 60px 0;
    border-top: 1px solid #eee;
    font-size: 0.8rem;
    color: #888;
}
.footer .footer-links {
    margin-top: 1rem;
    font-size: 0.85rem;
}
.footer .footer-links a {
    color: #555;
    text-decoration: none;
    transition: color 0.2s;
}
.footer .footer-links a:hover {
    color: #1A2B3C;
}
.footer .footer-links .sep {
    color: #ccc;
    margin: 0 0.6rem;
}

/* Reveal Utilities */
.reveal-text {
    opacity: 0;
    transform: translateY(30px);
}

.reveal-image {
    opacity: 0;
    clip-path: inset(100% 0 0 0);
}

/* ============================================================
   Mobile responsive — comprehensive (≤768px)
   ============================================================ */
@media (max-width: 768px) {
    /* Container */
    .container { padding: 0 20px; }

    /* Header */
    .header { padding: 16px 0; }
    .header-inner { padding: 0 16px; flex-wrap: wrap; gap: 8px; }
    .nav ul { gap: 14px; flex-wrap: wrap; justify-content: flex-end; }
    .nav a { font-size: 0.78rem; }
    .btn-contact { padding: 5px 14px; }
    .logo-main { font-size: 1.0rem; }
    .logo-sub { font-size: 0.6rem; }

    /* Hero */
    .hero { height: 90vh; }
    .hero-title { font-size: 1.4rem; letter-spacing: 0.03em; padding: 0 16px; line-height: 1.5; }
    .hero-tagline { font-size: 1rem; letter-spacing: 0.06em; padding: 0 16px; line-height: 1.6; margin: 0 0 12px; }
    .hero-subtitle { font-size: 0.9rem; letter-spacing: 0.1em; padding: 0 16px; line-height: 1.7; }
    .scroll-indicator { bottom: 24px; font-size: 0.7rem; }
    .scroll-indicator::after { height: 40px; }

    /* Sections */
    .section { padding: 80px 0; }
    .section-title { font-size: 1.7rem; margin-bottom: 48px; letter-spacing: 0.06em; }

    /* Concept */
    .concept-text { font-size: 1.0rem; line-height: 2; letter-spacing: 0.04em; }

    /* Technology */
    .tech-container { flex-direction: column; gap: 40px; }
    .tech-subtitle { font-size: 1.15rem; }
    .comparison-mockup { height: 240px; }
    .mockup-play-icon { width: 48px; height: 48px; font-size: 1.1rem; bottom: 18px; right: 18px; }
    .mockup-badge { top: 14px; left: 14px; padding: 4px 10px; font-size: 0.66rem; }
    .video-modal-close { top: -36px; font-size: 1.8rem; }

    /* About */
    .about-content { flex-direction: column; gap: 32px; align-items: stretch; }
    .about-profile, .company-info { flex: none; }
    .company-info { padding: 24px; width: 100%; }
    .company-info dl { font-size: 0.9rem; row-gap: 14px; }
    .company-info dt { width: 38%; }
    .company-info dd { width: 62%; }
    .profile-name { font-size: 1.2rem; margin-bottom: 20px; }
    .profile-greeting-title { font-size: 1.05rem; margin-top: 28px; }
    .profile-text, .profile-credentials { font-size: 0.9rem; line-height: 1.9; }

    /* Footer */
    .footer { padding: 40px 0; }
    .footer .footer-links { display: flex; flex-direction: column; gap: 8px; }
    .footer .footer-links .sep { display: none; }
}

/* === Release Banner (2026-05-30 正式リリース反映) === */
:root {
  --release-banner-height: 64px;
}
.release-banner {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: linear-gradient(135deg, #1A2B3C 0%, #2c4360 100%);
  color: #fff;
  padding: 12px 24px;
  text-align: center;
  font-size: 0.92rem;
  letter-spacing: 0.04em;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  z-index: 110;
  min-height: var(--release-banner-height);
  box-sizing: border-box;
  display: flex;
  align-items: center;
  justify-content: center;
}
.release-banner-inner {
  display: inline-flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}
.release-banner-badge {
  display: inline-block;
  padding: 3px 10px;
  background: #D9A441;
  color: #1A2B3C;
  font-weight: 700;
  border-radius: 3px;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
}
.release-banner-text { font-weight: 500; }
.release-banner-date {
  margin-left: 10px;
  opacity: 0.75;
  font-size: 0.85em;
}
.release-banner-cta {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(255,255,255,0.12);
  border: 1px solid rgba(255,255,255,0.3);
  color: #fff;
  text-decoration: none;
  border-radius: 4px;
  font-size: 0.88rem;
  font-weight: 500;
  transition: all 0.25s ease;
}
.release-banner-cta:hover {
  background: rgba(255,255,255,0.22);
  border-color: rgba(255,255,255,0.5);
}
@media (max-width: 640px) {
  :root { --release-banner-height: 92px; }
  .release-banner { font-size: 0.85rem; padding: 8px 12px; }
  .release-banner-inner { gap: 8px; }
  .release-banner-cta { padding: 5px 12px; font-size: 0.82rem; }
}