/* ═══════════════════════════════════════════════
   AssistA Studio — Dark Editorial Design
   Fusion of Readdy minimal + Stitch editorial
═══════════════════════════════════════════════ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Playfair+Display:ital,wght@0,400;0,700;1,400;1,700&display=swap');

:root {
    --color-bg: #0D0D0D;
    --color-surface: rgba(255, 255, 255, 0.04);
    --color-border: rgba(224, 224, 224, 0.1);
    --color-border-hover: rgba(224, 224, 224, 0.2);
    --color-primary: #C1C7C0;
    --color-primary-2: #d4d9d3;
    --color-accent: #C1C7C0;
    --color-text: #E0E0E0;
    --color-text-muted: #888888;
    --color-text-faint: #555555;
    --color-success: #A8B5A0;

    --radius-sm: 0px;
    --radius-md: 0px;
    --radius-lg: 0px;
    --radius-xl: 0px;
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --font-serif: 'Playfair Display', Georgia, serif;
    --nav-height: 80px;
    --max-w: 1200px;
    --transition-fast: 0.2s ease;
    --transition-mid: 0.5s ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    background: var(--color-bg);
    color: var(--color-text);
    font-family: var(--font-sans);
    font-size: 16px;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

::selection {
    background: rgba(193, 199, 192, 0.25);
    color: #fff;
}

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

a {
    color: inherit;
}

ul {
    list-style: none;
}

/* ── Utilities ─────────────────────────────── */
.container {
    width: 100%;
    max-width: var(--max-w);
    margin: 0 auto;
    padding: 0 clamp(24px, 4vw, 48px);
}

.section {
    padding: clamp(80px, 10vw, 140px) 0;
}

.serif-display {
    font-family: var(--font-serif);
    letter-spacing: -0.02em;
    line-height: 1.1;
}

.section-label {
    display: inline-block;
    font-size: 0.7rem;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    margin-bottom: 24px;
}

.gradient-text {
    background: linear-gradient(to right, var(--color-primary), #fff);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* ── Animation ─────────────────────────────── */
@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-on-scroll {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.7s ease, transform 0.7s ease;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ── Buttons ───────────────────────────────── */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    font-family: var(--font-sans);
    font-size: 0.7rem;
    font-weight: 500;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    cursor: pointer;
    border: 1px solid var(--color-border-hover);
    transition: all var(--transition-mid);
    text-decoration: none;
    background: transparent;
    color: var(--color-text);
}

.btn:hover {
    background: var(--color-text);
    color: var(--color-bg);
    border-color: var(--color-text);
}

.btn-primary {
    background: var(--color-text);
    color: var(--color-bg);
    border-color: var(--color-text);
}

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

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

.btn-ghost:hover {
    background: var(--color-text);
    color: var(--color-bg);
}

/* ── Tag (editorial label) ─────────────────── */
.tag {
    display: inline-block;
    font-size: 0.65rem;
    letter-spacing: 0.3em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    padding: 0;
    border: none;
    background: none;
}

/* ── Navigation ────────────────────────────── */
.site-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    padding: 0 clamp(24px, 4vw, 48px);
    height: var(--nav-height);
    display: flex;
    align-items: center;
    mix-blend-mode: difference;
    background: transparent;
    border-bottom: 1px solid transparent;
    transition: background 0.4s ease, border-color 0.4s ease, mix-blend-mode 0s;
}

.site-nav.scrolled {
    mix-blend-mode: normal;
    background: rgba(13, 13, 13, 0.95);
    border-bottom-color: var(--color-border);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
}

.nav-inner {
    width: 100%;
    max-width: var(--max-w);
    margin: 0 auto;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
}

.nav-logo-img {
    width: 32px;
    height: 32px;
    border-radius: 0;
    object-fit: cover;
    flex-shrink: 0;
}

.nav-logo-text {
    font-size: 0.85rem;
    font-weight: 500;
    color: #fff;
    letter-spacing: 0.12em;
    text-transform: uppercase;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 36px;
    list-style: none;
}

.nav-links a {
    font-size: 0.7rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.nav-links a:hover {
    color: #fff;
}

.nav-cta {
    display: flex;
    align-items: center;
}

.nav-hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-hamburger span {
    display: block;
    width: 24px;
    height: 1.5px;
    background: #fff;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav-hamburger span:nth-child(2) {
    width: 16px;
    margin-left: auto;
}

.nav-hamburger.active span:first-child {
    transform: translateY(6.5px) rotate(45deg);
}

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

.nav-hamburger.active span:last-child {
    transform: translateY(-6.5px) rotate(-45deg);
}

/* Mobile Menu */
.mobile-menu {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100dvh;
    background: var(--color-bg);
    z-index: 999;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    padding: 80px 48px;
    gap: 28px;
    transform: translateY(-100%);
    transition: transform 0.5s cubic-bezier(0.22, 1, 0.36, 1);
}

.mobile-menu.open {
    transform: translateY(0);
}

.mobile-link {
    font-family: var(--font-serif);
    font-size: 2rem;
    color: var(--color-text);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.mobile-link:hover {
    color: var(--color-primary);
}

/* ── Hero ──────────────────────────────────── */
.hero {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 0 0 clamp(60px, 8vw, 100px) 0;
    position: relative;
    overflow: hidden;
}

.hero-bg-grid {
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle at 20% 30%, rgba(193, 199, 192, 0.06) 0%, transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(193, 199, 192, 0.04) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    display: grid;
    grid-template-columns: repeat(12, 1fr);
    gap: 2rem;
    align-items: end;
}

.hero-main {
    grid-column: 1 / 8;
}

.hero-side {
    grid-column: 9 / 13;
    display: flex;
    flex-direction: column;
    gap: 32px;
}

.hero-eyebrow {
    margin-bottom: 32px;
    animation: fadeUp 0.6s ease both;
}

.hero-title {
    font-family: var(--font-serif);
    font-size: clamp(3rem, 7vw, 5.5rem);
    font-weight: 400;
    line-height: 1.05;
    letter-spacing: -0.02em;
    margin-bottom: 0;
    animation: fadeUp 0.6s 0.1s ease both;
}

.hero-title em {
    font-style: italic;
}

.hero-subtitle {
    font-size: 1rem;
    color: var(--color-text-muted);
    max-width: 420px;
    line-height: 1.8;
    margin-top: 40px;
    padding-left: 20px;
    border-left: 1px solid rgba(193, 199, 192, 0.3);
    animation: fadeUp 0.6s 0.2s ease both;
}

.hero-actions {
    display: flex;
    gap: 16px;
    margin-top: 40px;
    animation: fadeUp 0.6s 0.3s ease both;
}

.hero-stats {
    display: flex;
    gap: 48px;
    padding-top: 60px;
    border-top: 1px solid var(--color-border);
    animation: fadeUp 0.6s 0.35s ease both;
}

.hero-stat-value {
    font-family: var(--font-serif);
    font-size: 2rem;
    font-weight: 400;
    color: #fff;
}

.hero-stat-label {
    font-size: 0.65rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    margin-top: 6px;
}

/* ── Section Header ────────────────────────── */
.section-header {
    margin-bottom: 64px;
}

.section-title {
    font-family: var(--font-serif);
    font-size: clamp(2rem, 4.5vw, 3.5rem);
    font-weight: 400;
    letter-spacing: -0.02em;
    margin-bottom: 16px;
    line-height: 1.15;
}

.section-desc {
    color: var(--color-text-muted);
    font-size: 0.95rem;
    max-width: 520px;
    line-height: 1.8;
    font-style: italic;
    font-family: var(--font-serif);
}

/* ── Apps ───────────────────────────────────── */
.apps-section {
    background: transparent;
}

.apps-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: clamp(40px, 5vw, 80px);
}

.app-card {
    display: flex;
    flex-direction: column;
    gap: 20px;
    padding: 40px 36px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    transition: all var(--transition-mid);
    position: relative;
}

.app-card:nth-child(2) {
    margin-top: 60px;
}

.app-card:hover {
    border-color: var(--color-border-hover);
    transform: translateY(-4px);
}

.app-icon {
    width: 64px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 16px;
    overflow: hidden;
    flex-shrink: 0;
}

.app-icon img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transform: scale(1.05); /* 丸みの計算誤差による白い角を隠す */
}

.app-name {
    font-family: var(--font-sans);
    font-size: 1rem;
    font-weight: 600;
    color: #fff;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.app-desc {
    font-size: 0.88rem;
    color: var(--color-text-muted);
    line-height: 1.8;
    flex: 1;
}

.app-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
    margin-top: 8px;
    padding-top: 20px;
    border-top: 1px solid var(--color-border);
}

.app-badge {
    display: inline-block;
    font-size: 0.6rem;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    padding: 6px 14px;
    border: 1px solid var(--color-border);
}

.app-badge-ios {
    color: var(--color-text-muted);
}

.app-badge-available {
    color: var(--color-success);
    border-color: rgba(168, 181, 160, 0.3);
}

.app-badge-coming {
    color: var(--color-text-faint);
}

/* ── Values ────────────────────────────────── */
.values-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1px;
    background: var(--color-border);
}

.value-card {
    padding: 40px 32px;
    background: var(--color-bg);
    transition: background var(--transition-mid);
}

.value-card:hover {
    background: rgba(255, 255, 255, 0.02);
}

.value-icon {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    margin-bottom: 24px;
    border: 1px solid var(--color-border);
}

.vi-lock {
    border-color: rgba(245, 158, 11, 0.25);
}

.vi-spark {
    border-color: rgba(193, 199, 192, 0.25);
}

.vi-shield {
    border-color: rgba(96, 165, 250, 0.25);
}

.vi-refresh {
    border-color: rgba(168, 181, 160, 0.25);
}

.vi-access {
    border-color: rgba(168, 85, 247, 0.25);
}

.vi-chat {
    border-color: rgba(156, 163, 175, 0.25);
}

.value-title {
    font-family: var(--font-sans);
    font-size: 0.85rem;
    font-weight: 600;
    color: #fff;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    margin-bottom: 14px;
}

.value-desc {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    line-height: 1.8;
}

/* ── About ─────────────────────────────────── */
.about-section {
    background: rgba(255, 255, 255, 0.015);
    border-top: 1px solid var(--color-border);
    border-bottom: 1px solid var(--color-border);
}

.about-inner {
    display: grid;
    grid-template-columns: 5fr 7fr;
    gap: clamp(40px, 6vw, 100px);
    align-items: start;
}

.about-card-main {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    padding: 48px 36px;
    position: relative;
}

.about-avatar {
    width: 72px;
    height: 72px;
    overflow: hidden;
    margin-bottom: 24px;
}

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

.about-role {
    font-size: 0.6rem;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: var(--color-primary);
    margin-bottom: 8px;
}

.about-name {
    font-family: var(--font-serif);
    font-size: 1.3rem;
    font-weight: 400;
    color: #fff;
    margin-bottom: 20px;
}

.about-bio {
    font-size: 0.88rem;
    color: var(--color-text-muted);
    line-height: 1.8;
    margin-bottom: 24px;
}

.about-skills {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.skill-pill {
    font-size: 0.6rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    padding: 6px 14px;
    border: 1px solid var(--color-border);
    transition: all var(--transition-fast);
}

.skill-pill:hover {
    border-color: var(--color-border-hover);
    color: var(--color-text);
}

.about-content {
    padding-top: 12px;
}

.about-highlights {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-top: 32px;
}

.about-highlights li {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    padding-left: 28px;
    position: relative;
    line-height: 1.6;
}

.about-highlights li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 8px;
    width: 12px;
    height: 1px;
    background: var(--color-primary);
}

/* ── CTA ───────────────────────────────────── */
.cta-section {
    padding-bottom: clamp(80px, 10vw, 140px);
}

.cta-box {
    border: 1px solid var(--color-border);
    padding: clamp(48px, 6vw, 80px);
    text-align: center;
    background: var(--color-surface);
}

.cta-title {
    font-family: var(--font-serif);
    font-size: clamp(1.8rem, 3.5vw, 3rem);
    font-weight: 400;
    margin-bottom: 20px;
    line-height: 1.2;
}

.cta-desc {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    max-width: 520px;
    margin: 0 auto 40px;
    line-height: 1.8;
}

.cta-email-link {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 0.7rem;
    font-weight: 500;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--color-text);
    border: 1px solid var(--color-border-hover);
    background: transparent;
    padding: 14px 32px;
    transition: all var(--transition-mid);
    text-decoration: none;
}

.cta-email-link:hover {
    background: var(--color-text);
    color: var(--color-bg);
    border-color: var(--color-text);
}

/* ── Footer ────────────────────────────────── */
.site-footer {
    border-top: 1px solid var(--color-border);
    padding: 80px 0 40px;
}

.footer-inner {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 60px;
    padding-bottom: 60px;
}

.footer-brand p {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    line-height: 1.7;
    margin-top: 20px;
    max-width: 320px;
}

.footer-col-title {
    font-size: 0.6rem;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    color: var(--color-text-muted);
    margin-bottom: 20px;
}

.footer-links li+li {
    margin-top: 14px;
}

.footer-links a {
    font-size: 0.82rem;
    color: var(--color-text-muted);
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

.footer-bottom {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-top: 32px;
    border-top: 1px solid var(--color-border);
}

.footer-copy {
    font-size: 0.6rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text-faint);
}

.footer-legal {
    display: flex;
    gap: 28px;
}

.footer-legal a {
    font-size: 0.7rem;
    color: var(--color-text-faint);
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

/* ── Responsive ────────────────────────────── */
@media (max-width: 900px) {

    .nav-links,
    .nav-cta {
        display: none;
    }

    .nav-hamburger {
        display: flex;
    }

    .hero-content {
        display: flex;
        flex-direction: column;
    }

    .hero-main,
    .hero-side {
        width: 100%;
    }

    .hero-title {
        font-size: clamp(2.5rem, 10vw, 3.5rem);
    }

    .hero-stats {
        gap: 32px;
        flex-wrap: wrap;
    }

    .apps-grid {
        grid-template-columns: 1fr;
    }

    .app-card:nth-child(2) {
        margin-top: 0;
    }

    .values-grid {
        grid-template-columns: 1fr;
    }

    .about-inner {
        grid-template-columns: 1fr;
    }

    .footer-inner {
        grid-template-columns: 1fr;
        gap: 40px;
    }
}

/* ── Prose (Privacy Policy etc.) ───────────── */
.privacy-prose h2 {
    font-family: var(--font-serif);
    font-size: 1.4rem;
    font-weight: 400;
    color: #fff;
    margin-top: 56px;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--color-border);
}

.privacy-prose h3 {
    font-family: var(--font-sans);
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-text);
    margin-top: 32px;
    margin-bottom: 12px;
}

.privacy-prose p {
    font-size: 0.9rem;
    color: var(--color-text-muted);
    line-height: 1.9;
    margin-bottom: 16px;
}

.privacy-prose ul {
    list-style: none;
    padding: 0;
    margin-bottom: 20px;
}

.privacy-prose ul li {
    font-size: 0.88rem;
    color: var(--color-text-muted);
    line-height: 1.8;
    padding-left: 24px;
    position: relative;
    margin-bottom: 8px;
}

.privacy-prose ul li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 10px;
    width: 10px;
    height: 1px;
    background: var(--color-primary);
}

.privacy-prose a {
    color: var(--color-primary);
    text-decoration: none;
    border-bottom: 1px solid rgba(193, 199, 192, 0.3);
    transition: all var(--transition-fast);
}

.privacy-prose a:hover {
    color: #fff;
    border-color: #fff;
}

.privacy-prose strong {
    color: var(--color-text);
    font-weight: 600;
}