/* === Onedrop LP v2 - Full Rewrite === */

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

:root {
    --primary: #2E8BC0;
    --primary-dark: #1A6694;
    --primary-light: #66B2D6;
    --primary-50: #EBF5FB;
    --primary-100: #C5E4F3;
    --accent: #E6802E;
    --accent-light: #F5A95E;
    --success: #3EA33E;
    --success-light: #E8F5E9;
    --error: #D94B4B;
    --error-light: #FDECEC;
    --gray-50: #F8FAFB;
    --gray-100: #F1F4F6;
    --gray-200: #E2E8ED;
    --gray-300: #CBD4DC;
    --gray-400: #9BA8B5;
    --gray-500: #6B7C8A;
    --gray-700: #344150;
    --gray-800: #1F2D3D;
    --gray-900: #0F1923;
    --text: #1F2D3D;
    --text-secondary: #6B7C8A;
    --text-muted: #9BA8B5;
    --bg: #fff;
    --bg-alt: #F8FAFB;
    --border: #E2E8ED;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;
    --shadow-sm: 0 1px 3px rgba(15,25,35,.06);
    --shadow-md: 0 4px 12px rgba(15,25,35,.08);
    --shadow-lg: 0 12px 32px rgba(15,25,35,.10);
    --shadow-xl: 0 24px 64px rgba(15,25,35,.12);
    --transition: .3s cubic-bezier(.4,0,.2,1);
    --transition-fast: .15s cubic-bezier(.4,0,.2,1);
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; }
}

html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }
body { font-family: 'Noto Sans JP','Inter',-apple-system,sans-serif; color: var(--text); background: var(--bg); line-height: 1.75; overflow-x: hidden; }
.container { max-width: 1100px; margin: 0 auto; padding: 0 1.5rem; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* --- Nav --- */
.navbar { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; padding: .75rem 0; background: rgba(255,255,255,.85); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px); border-bottom: 1px solid transparent; transition: var(--transition); }
.navbar.scrolled { border-bottom-color: var(--border); box-shadow: var(--shadow-sm); }
.nav-container { display: flex; align-items: center; justify-content: space-between; }
.nav-logo { display: flex; align-items: center; gap: .4rem; font-weight: 700; font-size: 1.2rem; }
.logo-icon { display: flex; align-items: center; }
.logo-text { background: linear-gradient(135deg,var(--primary),var(--primary-dark)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.nav-links { display: flex; list-style: none; gap: 1.75rem; }
.nav-links a { font-size: .8125rem; font-weight: 500; color: var(--text-secondary); transition: var(--transition-fast); }
.nav-links a:hover { color: var(--primary); }
.nav-cta { display: flex; align-items: center; gap: .4rem; padding: .4rem 1rem; border-radius: var(--radius-full); font-size: .8125rem; font-weight: 600; background: var(--gray-900); color: #fff; transition: var(--transition); }
.nav-cta:hover { background: var(--gray-700); }
.nav-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 4px; }
.nav-toggle span { width: 22px; height: 2px; background: var(--text); border-radius: 2px; transition: var(--transition); }
.nav-toggle.active span:nth-child(1) { transform: rotate(45deg) translate(5px,5px); }
.nav-toggle.active span:nth-child(2) { opacity: 0; }
.nav-toggle.active span:nth-child(3) { transform: rotate(-45deg) translate(5px,-5px); }

/* --- Buttons --- */
.btn { display: inline-flex; align-items: center; gap: .5rem; padding: .8rem 1.5rem; border-radius: var(--radius-full); font-size: .9rem; font-weight: 600; transition: var(--transition); cursor: pointer; border: none; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn-outline { background: transparent; color: var(--text); border: 1.5px solid var(--border); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }
.btn-cta { background: #fff; color: var(--gray-900); font-size: 1rem; padding: 1rem 2rem; box-shadow: var(--shadow-md); }
.btn-cta:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }

/* --- Section shared --- */
.section-header { text-align: center; margin-bottom: 3.5rem; }
.section-tag { display: inline-block; padding: .15rem 1rem; background: var(--primary-50); color: var(--primary-dark); border-radius: var(--radius-full); font-size: .8rem; font-weight: 600; margin-bottom: 1rem; border: 1px solid var(--primary-100); }
.section-title { font-size: clamp(1.6rem,3.5vw,2.25rem); font-weight: 800; line-height: 1.35; color: var(--gray-900); }
.section-description { font-size: 1rem; color: var(--text-secondary); max-width: 560px; margin: 1rem auto 0; line-height: 1.8; }

/* --- Hero --- */
.hero { position: relative; padding: 8rem 0 4rem; min-height: 100vh; display: flex; align-items: center; }
.hero-bg-shapes { position: absolute; inset: 0; pointer-events: none; overflow: hidden; }
.shape { position: absolute; border-radius: 50%; opacity: .05; }
.shape-1 { width: 500px; height: 500px; background: var(--primary); top: -150px; right: -100px; }
.shape-2 { width: 350px; height: 350px; background: var(--accent); bottom: -80px; left: -80px; }
.hero-container { display: grid; grid-template-columns: 1fr 1fr; gap: 4rem; align-items: center; }
.hero-badge { display: inline-block; padding: .35rem 1rem; background: var(--primary-50); color: var(--primary-dark); border-radius: var(--radius-full); font-size: .8rem; font-weight: 600; margin-bottom: 1.5rem; border: 1px solid var(--primary-100); }
.hero-title { font-size: clamp(2rem,4.5vw,3.25rem); font-weight: 900; line-height: 1.2; letter-spacing: -.02em; margin-bottom: 1.5rem; color: var(--gray-900); }
.title-accent { color: var(--primary); }
.title-highlight { position: relative; }
.title-highlight::after { content: ''; position: absolute; bottom: 2px; left: -3px; right: -3px; height: 10px; background: var(--accent-light); opacity: .3; border-radius: 3px; z-index: -1; }
.hero-description { font-size: 1rem; color: var(--text-secondary); line-height: 1.85; margin-bottom: 2rem; max-width: 500px; }
.hero-pillars { display: flex; flex-direction: column; gap: .6rem; margin-bottom: 2rem; padding: 1.25rem 0; border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.hero-pillar { display: flex; align-items: center; gap: .6rem; }
.pillar-icon { color: var(--primary); display: flex; align-items: center; flex-shrink: 0; }
.pillar-text { font-size: .9rem; font-weight: 600; color: var(--gray-800); }
.hero-actions { display: flex; gap: .75rem; flex-wrap: wrap; margin-bottom: 1rem; }
.hero-oss-note { font-size: .75rem; color: var(--text-muted); }

/* --- Hero Mockup (Windows style) --- */
.hero-visual { position: relative; }
.app-mockup { position: relative; }
.mockup-window { background: #fff; border-radius: var(--radius-md); box-shadow: var(--shadow-xl); overflow: hidden; border: 1px solid var(--gray-200); }
.student-window { animation: float 6s ease-in-out infinite; }
.admin-window { position: absolute; bottom: -20px; right: -20px; width: 260px; animation: float-admin 6s ease-in-out infinite; z-index: 3; }
@keyframes float { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-8px)} }
@keyframes float-admin { 0%,100%{transform:translateY(0)} 50%{transform:translateY(-6px)} }

/* Windows-style title bar */
.window-bar { display: flex; align-items: center; gap: .5rem; padding: .3rem .6rem; background: var(--gray-100); border-bottom: 1px solid var(--gray-200); min-height: 30px; }
.window-bar-icon { color: var(--primary); display: flex; align-items: center; }
.window-title { font-size: .7rem; color: var(--text-secondary); font-weight: 500; flex: 1; }
.window-controls { display: flex; gap: 0; margin-left: auto; }
.wc { display: flex; align-items: center; justify-content: center; width: 28px; height: 22px; font-size: .6rem; color: var(--text-muted); cursor: default; }
.wc:hover { background: var(--gray-200); }
.wc-close:hover { background: var(--error); color: #fff; }

.window-content { padding: 1.25rem; }
.qr-scan-area { display: flex; flex-direction: column; align-items: center; padding: 2rem 1rem; border: 2px dashed var(--primary-light); border-radius: var(--radius-md); background: var(--primary-50); position: relative; overflow: hidden; }
.qr-icon { color: var(--primary); margin-bottom: .75rem; }
.scan-text { font-size: .8rem; color: var(--primary-dark); font-weight: 500; }
.scan-line { position: absolute; width: 80%; height: 2px; background: linear-gradient(90deg,transparent,var(--primary),transparent); animation: scan 2.5s ease-in-out infinite; }
@keyframes scan { 0%,100%{top:15%;opacity:0} 10%{opacity:1} 50%{top:85%;opacity:1} 65%{opacity:0} }
.mock-student-info { display: flex; align-items: center; gap: .75rem; margin-top: 1rem; padding: .6rem .8rem; background: var(--success-light); border-radius: var(--radius-sm); }
.student-avatar { width: 32px; height: 32px; border-radius: 50%; background: var(--success); color: #fff; display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: .75rem; }
.student-name-mock { font-weight: 600; font-size: .85rem; }
.student-id-mock { font-size: .7rem; color: var(--success); }
.admin-content { display: flex; flex-direction: column; gap: .35rem; padding: .6rem; }
.admin-btn-mock { padding: .35rem .6rem; border-radius: var(--radius-sm); color: #fff; font-size: .7rem; font-weight: 600; text-align: center; }
.admin-btn-mock.primary { background: var(--primary); }
.admin-btn-mock.success { background: var(--success); }
.admin-btn-mock.accent { background: var(--accent); }

/* --- Audience --- */
.audience { padding: 3rem 0; background: var(--bg-alt); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.audience-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 1.25rem; }
.audience-card { text-align: center; padding: 1.5rem 1rem; background: #fff; border-radius: var(--radius-lg); border: 1px solid var(--border); transition: var(--transition); }
.audience-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); border-color: var(--primary-light); }
.audience-icon { display: flex; justify-content: center; align-items: center; width: 48px; height: 48px; margin: 0 auto .75rem; border-radius: var(--radius-md); background: var(--primary-50); color: var(--primary); }
.audience-card h3 { font-size: .95rem; font-weight: 700; margin-bottom: .3rem; color: var(--gray-800); }
.audience-card p { font-size: .8rem; color: var(--text-secondary); line-height: 1.6; }

/* --- Problems + Solutions (paired) --- */
.problems { padding: 5rem 0; }
.problems-solutions-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 1.5rem; }
.ps-card { background: #fff; border-radius: var(--radius-lg); border: 1px solid var(--border); padding: 1.75rem; display: flex; flex-direction: column; gap: 1rem; transition: var(--transition); }
.ps-card:hover { box-shadow: var(--shadow-md); }
.ps-problem, .ps-solution { display: flex; gap: .75rem; align-items: flex-start; }
.ps-icon { width: 40px; height: 40px; border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.problem-icon { background: var(--error-light); color: var(--error); }
.solution-icon { background: var(--success-light); color: var(--success); }
.ps-problem h3, .ps-solution h3 { font-size: .9rem; font-weight: 700; color: var(--gray-800); margin-bottom: .15rem; }
.ps-problem p { font-size: .825rem; color: var(--text-secondary); line-height: 1.6; }
.ps-solution p { font-size: .825rem; color: var(--text-secondary); line-height: 1.6; }
.ps-arrow { display: flex; justify-content: center; color: var(--gray-300); }

/* --- Features --- */
.solutions { padding: 5rem 0; background: var(--bg-alt); }
.features-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 1.25rem; }
.feature-card { padding: 1.75rem; background: #fff; border-radius: var(--radius-lg); border: 1px solid var(--border); transition: var(--transition); }
.feature-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }
.feature-icon-wrapper { width: 52px; height: 52px; border-radius: var(--radius-md); background: var(--primary-50); color: var(--primary); display: flex; align-items: center; justify-content: center; margin-bottom: 1rem; }
.feature-card h3 { font-size: 1rem; font-weight: 700; margin-bottom: .4rem; color: var(--gray-800); }
.feature-card p { font-size: .85rem; color: var(--text-secondary); line-height: 1.7; }

/* --- How it works --- */
.how-it-works { padding: 5rem 0; }
.steps { max-width: 600px; margin: 0 auto; display: flex; flex-direction: column; gap: 2rem; }
.step { display: flex; gap: 1.5rem; align-items: flex-start; }
.step-number { width: 44px; height: 44px; border-radius: 50%; background: var(--primary); color: #fff; display: flex; align-items: center; justify-content: center; font-family: 'Inter',sans-serif; font-size: 1.1rem; font-weight: 800; flex-shrink: 0; }
.step-content h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: .25rem; color: var(--gray-800); }
.step-content p { font-size: .9rem; color: var(--text-secondary); line-height: 1.75; }
.step-content code { background: var(--gray-100); padding: 1px 6px; border-radius: 4px; font-size: .85rem; font-family: Consolas,monospace; color: var(--primary-dark); }

/* --- Results (Changes) --- */
.results { padding: 5rem 0; background: var(--bg-alt); }
.changes-list { max-width: 700px; margin: 0 auto; display: flex; flex-direction: column; gap: 1.5rem; }
.change-item { display: flex; gap: 1rem; align-items: flex-start; padding: 1.5rem; background: #fff; border-radius: var(--radius-lg); border: 1px solid var(--border); }
.change-icon { width: 40px; height: 40px; border-radius: var(--radius-sm); background: var(--primary-50); color: var(--primary); display: flex; align-items: center; justify-content: center; flex-shrink: 0; }
.change-content h3 { font-size: .95rem; font-weight: 700; color: var(--gray-800); margin-bottom: .3rem; }
.change-content p { font-size: .85rem; color: var(--text-secondary); line-height: 1.75; }

/* --- Tech / Architecture --- */
.tech { padding: 5rem 0; }
.arch-diagram { max-width: 800px; margin: 0 auto 2rem; }
.arch-layer { padding: 1.5rem; border-radius: var(--radius-lg); margin-bottom: 1rem; }
.app-layer { background: var(--primary-50); border: 1px solid var(--primary-100); }
.arch-layer-title { font-size: .9rem; font-weight: 700; color: var(--gray-800); margin-bottom: 1rem; display: flex; align-items: center; gap: .5rem; }
.arch-badge { font-size: .65rem; font-weight: 600; padding: 2px 8px; background: var(--primary); color: #fff; border-radius: var(--radius-full); }
.arch-boxes { display: grid; grid-template-columns: repeat(auto-fit,minmax(200px,1fr)); gap: 1rem; }
.arch-box { padding: 1rem; background: #fff; border-radius: var(--radius-md); border: 1px solid var(--border); }
.arch-box h5 { font-size: .85rem; font-weight: 700; margin-bottom: .35rem; color: var(--gray-800); }
.arch-box ul { list-style: none; }
.arch-box li { font-size: .75rem; color: var(--text-secondary); padding-left: .75rem; position: relative; line-height: 1.8; }
.arch-box li::before { content: '·'; position: absolute; left: 0; color: var(--primary); font-weight: 700; }
.arch-box p { font-size: .75rem; color: var(--text-secondary); }
.student-box { border-left: 3px solid var(--primary); }
.admin-box { border-left: 3px solid var(--accent); }
.api-box { border-left: 3px solid var(--success); }
.printer-box { border-left: 3px solid var(--accent); }
.arch-connectors { display: flex; justify-content: center; gap: 4rem; margin: .75rem 0; }
.connector-line { width: 2px; height: 30px; background: linear-gradient(var(--primary-light),var(--gray-300)); }
.external-layer .arch-boxes { grid-template-columns: repeat(3,1fr); }
.tech-tags { display: flex; flex-wrap: wrap; justify-content: center; gap: .5rem; max-width: 800px; margin: 0 auto; }
.tech-tag { padding: .25rem .75rem; background: var(--gray-100); border-radius: var(--radius-full); font-size: .75rem; font-weight: 500; color: var(--text-secondary); border: 1px solid var(--border); }

/* --- AI Dev --- */
.ai-dev { padding: 5rem 0; background: var(--gray-900); color: #fff; }
.ai-dev .section-tag { background: rgba(46,139,192,.15); color: var(--primary-light); border-color: rgba(46,139,192,.25); }
.ai-dev .section-title { color: #fff; }
.ai-dev .section-description { color: rgba(255,255,255,.55); }
.ai-dev-content { max-width: 700px; margin: 0 auto; }
.ai-dev-stats { display: grid; grid-template-columns: repeat(3,1fr); gap: 1rem; margin-bottom: 2rem; }
.ai-stat { text-align: center; padding: 1.25rem; background: rgba(255,255,255,.05); border-radius: var(--radius-lg); border: 1px solid rgba(255,255,255,.08); }
.ai-stat-value { font-family: 'Inter',sans-serif; font-size: 1.5rem; font-weight: 800; color: var(--primary-light); display: block; }
.ai-stat-label { font-size: .75rem; color: rgba(255,255,255,.45); }
.ai-dev-flow { padding: 1.5rem; background: rgba(255,255,255,.04); border-radius: var(--radius-lg); border: 1px solid rgba(255,255,255,.08); }
.ai-dev-flow h4 { font-size: .9rem; margin-bottom: 1rem; color: rgba(255,255,255,.7); }
.flow-steps { display: flex; align-items: center; gap: .4rem; flex-wrap: wrap; justify-content: center; }
.flow-step { display: flex; flex-direction: column; align-items: center; gap: 2px; }
.flow-role { font-size: .6rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; padding: 1px 6px; border-radius: var(--radius-full); }
.flow-role.human { background: rgba(230,128,46,.2); color: var(--accent-light); }
.flow-role.ai { background: rgba(46,139,192,.2); color: var(--primary-light); }
.flow-action { font-size: .75rem; color: rgba(255,255,255,.6); }
.flow-arrow { color: rgba(255,255,255,.2); font-size: 1rem; }
.flow-caption { text-align: center; margin-top: 1rem; font-size: .75rem; color: rgba(255,255,255,.35); font-style: italic; }

/* --- CTA --- */
.cta-section { padding: 5rem 0; background: linear-gradient(135deg,var(--primary),var(--primary-dark)); color: #fff; text-align: center; }
.cta-title { font-size: clamp(1.4rem,3vw,2rem); font-weight: 800; margin-bottom: .75rem; }
.cta-description { font-size: 1rem; color: rgba(255,255,255,.8); margin-bottom: 2rem; }
.beta-benefits { display: flex; flex-direction: column; gap: .6rem; margin-bottom: 2rem; max-width: 440px; margin-left: auto; margin-right: auto; text-align: left; }
.beta-benefit { display: flex; align-items: center; gap: .6rem; font-size: .9rem; color: rgba(255,255,255,.85); }
.beta-benefit strong { color: #fff; }
.beta-benefit-icon { color: rgba(255,255,255,.7); flex-shrink: 0; display: flex; }
.cta-actions { margin-bottom: 1rem; }
.cta-note { font-size: .8rem; color: rgba(255,255,255,.45); font-style: italic; }

/* --- Footer --- */
.footer { padding: 2rem 0 1.5rem; background: var(--gray-900); color: #fff; }
.footer-container { display: flex; align-items: center; justify-content: space-between; margin-bottom: 1rem; padding-bottom: 1rem; border-bottom: 1px solid rgba(255,255,255,.08); }
.footer-brand { display: flex; align-items: center; gap: .4rem; }
.footer-tagline { font-size: .8rem; color: rgba(255,255,255,.4); margin-left: .75rem; }
.footer-link { display: flex; align-items: center; gap: .4rem; font-size: .8rem; color: rgba(255,255,255,.5); transition: var(--transition-fast); }
.footer-link:hover { color: #fff; }
.footer-copy { font-size: .75rem; color: rgba(255,255,255,.25); text-align: center; }

/* --- Scroll Animations --- */
.fade-in { opacity: 0; transform: translateY(24px); transition: opacity .5s ease, transform .5s ease; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* --- Responsive --- */
@media (max-width: 1024px) {
    .hero-container { grid-template-columns: 1fr; gap: 2.5rem; }
    .hero-visual { max-width: 450px; margin: 0 auto; }
    .features-grid { grid-template-columns: repeat(2,1fr); }
    .audience-grid { grid-template-columns: repeat(2,1fr); }
    .external-layer .arch-boxes { grid-template-columns: repeat(2,1fr); }
}

@media (max-width: 768px) {
    .nav-links { position: fixed; top: 56px; left: 0; right: 0; background: #fff; flex-direction: column; align-items: center; padding: 1.5rem; gap: 1rem; border-bottom: 1px solid var(--border); box-shadow: var(--shadow-md); display: none; }
    .nav-links.active { display: flex; }
    .nav-cta { display: none; }
    .nav-toggle { display: flex; }
    .hero { padding: 6rem 0 2.5rem; min-height: auto; }
    .hero-stats { flex-direction: row; flex-wrap: wrap; gap: 1.25rem; }
    .stat-divider { display: none; }
    .problems-solutions-grid { grid-template-columns: 1fr; }
    .features-grid { grid-template-columns: 1fr; }
    .audience-grid { grid-template-columns: 1fr 1fr; }
    .ai-dev-stats { grid-template-columns: repeat(3,1fr); }
    .arch-boxes { grid-template-columns: 1fr !important; }
    .admin-window { display: none; }
    .footer-container { flex-direction: column; gap: .75rem; text-align: center; }
    .footer-brand { flex-direction: column; }
    .footer-tagline { margin-left: 0; }
}

@media (max-width: 480px) {
    .audience-grid { grid-template-columns: 1fr; }
    .ai-dev-stats { grid-template-columns: 1fr; }
    .hero-actions { flex-direction: column; }
    .btn { justify-content: center; width: 100%; }
}