/* =========================================
   KiKu — kiku-notes.com
   Minimalist. Japanese-inspired. Purposeful.
   ========================================= */

:root {
    /* KiKu palette — from sumi-e ink wash */
    --kiku-indigo: #4a5170;
    --kiku-indigo-light: #6168a0;
    --kiku-red: #b25151;
    --kiku-green: #629a7d;
    --kiku-orange: #be8d58;

    /* Neutrals */
    --ink: #1a1a1f;
    --ink-soft: #2c2c35;
    --stone: #6b6b78;
    --mist: #9e9eac;
    --cloud: #d4d4dc;
    --paper: #f5f4f0;
    --white: #fefefe;

    /* Spacing */
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 2rem;
    --space-lg: 4rem;
    --space-xl: 6rem;
    --space-2xl: 10rem;

    /* Typography */
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
    --text-xs: 0.75rem;
    --text-sm: 0.875rem;
    --text-base: 1rem;
    --text-lg: 1.125rem;
    --text-xl: 1.375rem;
    --text-2xl: 1.75rem;
    --text-3xl: 2.5rem;
    --text-4xl: 3.5rem;

    /* Motion */
    --ease: cubic-bezier(0.25, 0.1, 0.25, 1);
    --duration: 0.6s;
}

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

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font);
    font-weight: 300;
    color: var(--ink);
    background: var(--paper);
    line-height: 1.7;
    overflow-x: hidden;
}

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

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

/* ---- Ink wash background ---- */
.ink-wash {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    background:
        radial-gradient(ellipse at 20% 0%, rgba(74, 81, 112, 0.03) 0%, transparent 60%),
        radial-gradient(ellipse at 80% 100%, rgba(74, 81, 112, 0.02) 0%, transparent 50%);
}

/* ---- Container ---- */
.container {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 var(--space-md);
}

/* ---- Section headers ---- */
.section-header {
    text-align: center;
    margin-bottom: var(--space-xl);
}

.section-header h2 {
    font-size: var(--text-3xl);
    font-weight: 200;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-xs);
}

.section-header p {
    font-size: var(--text-lg);
    color: var(--stone);
    font-weight: 300;
}

/* ==============================
   Navigation
   ============================== */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: var(--space-sm) 0;
    transition: background var(--duration) var(--ease), box-shadow var(--duration) var(--ease);
}

.nav.scrolled {
    background: rgba(245, 244, 240, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    box-shadow: 0 1px 0 rgba(0,0,0,0.04);
}

.nav-inner {
    max-width: 1080px;
    margin: 0 auto;
    padding: 0 var(--space-md);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    font-size: var(--text-lg);
    font-weight: 300;
    letter-spacing: -0.01em;
}

.nav-icon {
    width: 28px;
    height: 28px;
    border-radius: 6px;
}

.nav-cta {
    font-size: var(--text-sm);
    font-weight: 400;
    color: var(--kiku-indigo);
    padding: 0.45rem 1.2rem;
    border: 1px solid rgba(74, 81, 112, 0.2);
    border-radius: 100px;
    transition: all 0.3s var(--ease);
}

.nav-cta:hover {
    background: var(--kiku-indigo);
    color: var(--white);
    border-color: var(--kiku-indigo);
}

/* ==============================
   Hero
   ============================== */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-2xl) var(--space-md) var(--space-xl);
    z-index: 1;
}

.hero-content {
    text-align: center;
    max-width: 680px;
    position: relative;
    z-index: 2;
}

.hero-badge {
    display: inline-block;
    font-size: var(--text-xs);
    font-weight: 500;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--kiku-indigo);
    background: rgba(74, 81, 112, 0.06);
    padding: 0.3rem 1rem;
    border-radius: 100px;
    margin-bottom: var(--space-md);
}

.hero h1 {
    font-size: var(--text-4xl);
    font-weight: 200;
    letter-spacing: -0.03em;
    line-height: 1.15;
    margin-bottom: var(--space-md);
    color: var(--ink);
}

.hero-sub {
    font-size: var(--text-xl);
    color: var(--stone);
    line-height: 1.6;
    margin-bottom: var(--space-lg);
    font-weight: 300;
}

.hero-actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    flex-wrap: wrap;
}

/* Buttons */
.btn-primary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: var(--text-sm);
    font-weight: 400;
    color: var(--white);
    background: var(--kiku-indigo);
    padding: 0.75rem 2rem;
    border-radius: 100px;
    transition: all 0.3s var(--ease);
    border: none;
    cursor: pointer;
}

.btn-primary:hover {
    background: var(--kiku-indigo-light);
    transform: translateY(-1px);
    box-shadow: 0 4px 20px rgba(74, 81, 112, 0.2);
}

.btn-primary.btn-large {
    font-size: var(--text-base);
    padding: 0.9rem 2.5rem;
}

.btn-ghost {
    display: inline-flex;
    align-items: center;
    font-size: var(--text-sm);
    font-weight: 400;
    color: var(--stone);
    padding: 0.75rem 1.5rem;
    transition: color 0.3s var(--ease);
}

.btn-ghost:hover {
    color: var(--ink);
}

/* Zen ripple decoration */
.enso-container {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 400px;
    height: 400px;
    z-index: 1;
    overflow: hidden;
    border-radius: 50%;
}

.ripple-ring {
    position: absolute;
    top: 50%;
    left: 50%;
    width: 80px;
    height: 80px;
    margin-top: -40px;
    margin-left: -40px;
    border-radius: 50%;
    border: 1px solid var(--kiku-indigo);
    opacity: 0;
    animation: rippleExpand 4s cubic-bezier(0.25, 0.1, 0.25, 1) infinite;
}

.ripple-ring-1 { animation-delay: 0s; }
.ripple-ring-2 { animation-delay: 1.33s; }
.ripple-ring-3 { animation-delay: 2.66s; }

@keyframes rippleExpand {
    0% {
        transform: scale(1);
        opacity: 0.12;
    }
    100% {
        transform: scale(4.5);
        opacity: 0;
    }
}

/* ==============================
   Philosophy
   ============================== */
.philosophy {
    padding: var(--space-xl) 0;
    position: relative;
    z-index: 1;
}

.philosophy-text {
    max-width: 640px;
    margin: 0 auto;
    text-align: center;
    font-size: var(--text-lg);
    line-height: 1.8;
    color: var(--stone);
    font-weight: 300;
    position: relative;
}

.philosophy-text em {
    color: var(--kiku-indigo);
    font-style: normal;
    font-weight: 400;
}

.jp-char {
    display: block;
    font-size: 3rem;
    color: var(--kiku-indigo);
    opacity: 0.12;
    margin-bottom: var(--space-sm);
    font-weight: 200;
}

/* ==============================
   Features
   ============================== */
.features {
    padding: var(--space-2xl) 0 var(--space-xl);
    position: relative;
    z-index: 1;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-md);
}

.feature-card {
    padding: var(--space-md);
    border-radius: 16px;
    transition: all 0.4s var(--ease);
    border: 1px solid transparent;
}

.feature-card:hover {
    background: var(--white);
    border-color: rgba(0,0,0,0.04);
    box-shadow: 0 4px 24px rgba(0,0,0,0.03);
}

.feature-icon {
    color: var(--kiku-indigo);
    margin-bottom: var(--space-sm);
    opacity: 0.7;
    transition: opacity 0.4s var(--ease), color 0.4s var(--ease);
}

.feature-card:hover .feature-icon {
    opacity: 1;
    color: var(--ink);
}

.feature-card h3 {
    font-size: var(--text-base);
    font-weight: 400;
    margin-bottom: var(--space-xs);
    letter-spacing: -0.01em;
}

.feature-card p {
    font-size: var(--text-sm);
    color: var(--stone);
    line-height: 1.65;
}

/* ==============================
   How it works
   ============================== */
.how-it-works {
    padding: var(--space-xl) 0 var(--space-2xl);
    position: relative;
    z-index: 1;
}

.steps {
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: 0;
    max-width: 900px;
    margin: 0 auto;
}

.step {
    flex: 1;
    text-align: center;
    padding: 0 var(--space-md);
}

.step-number {
    font-size: var(--text-2xl);
    color: var(--kiku-indigo);
    opacity: 0.15;
    margin-bottom: var(--space-sm);
    font-weight: 200;
    animation: breathe 6s ease-in-out infinite;
}

.step:nth-child(1) .step-number { animation-delay: 0s; }
.step:nth-child(2) .step-number { animation-delay: 2s; }
.step:nth-child(3) .step-number { animation-delay: 4s; }

@keyframes breathe {
    0%, 100% { opacity: 0.15; transform: scale(1); }
    33% { opacity: 0.4; transform: scale(1.08); }
    66% { opacity: 0.15; transform: scale(1); }
}

.step h3 {
    font-size: var(--text-lg);
    font-weight: 400;
    margin-bottom: var(--space-xs);
    letter-spacing: -0.01em;
}

.step p {
    font-size: var(--text-sm);
    color: var(--stone);
    line-height: 1.65;
}


/* ==============================
   Privacy
   ============================== */
.privacy {
    padding: var(--space-xl) 0;
    position: relative;
    z-index: 1;
}

.privacy-content {
    max-width: 620px;
    margin: 0 auto;
    text-align: center;
}

.privacy-icon {
    color: var(--kiku-indigo);
    opacity: 0.4;
    margin-bottom: var(--space-md);
}

.privacy-content h2 {
    font-size: var(--text-2xl);
    font-weight: 200;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-sm);
}

.privacy-content p {
    font-size: var(--text-base);
    color: var(--stone);
    line-height: 1.7;
}

/* ==============================
   Download
   ============================== */
.download {
    padding: var(--space-2xl) 0;
    position: relative;
    z-index: 1;
}

.download-content {
    text-align: center;
}

.download-icon {
    width: 96px;
    height: 96px;
    border-radius: 22px;
    margin: 0 auto var(--space-md);
    box-shadow: 0 8px 40px rgba(0,0,0,0.06);
}

.download-content h2 {
    font-size: var(--text-3xl);
    font-weight: 200;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-sm);
}

.download-content p {
    font-size: var(--text-lg);
    color: var(--stone);
    margin-bottom: var(--space-md);
    font-weight: 300;
}

.download-meta {
    display: block;
    margin-top: var(--space-sm);
    font-size: var(--text-xs);
    color: var(--mist);
    letter-spacing: 0.02em;
}

/* ==============================
   Footer
   ============================== */
.footer {
    padding: var(--space-lg) 0;
    border-top: 1px solid rgba(0,0,0,0.04);
    position: relative;
    z-index: 1;
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: var(--text-sm);
    font-weight: 300;
    color: var(--stone);
}

.footer-icon {
    width: 20px;
    height: 20px;
    border-radius: 4px;
    opacity: 0.6;
}

.footer-copy {
    font-size: var(--text-xs);
    color: var(--mist);
}

/* ==============================
   Capabilities
   ============================== */
.capabilities {
    padding: var(--space-xl) 0 var(--space-2xl);
    position: relative;
    z-index: 1;
}

.capability-list {
    max-width: 720px;
    margin: 0 auto var(--space-xl);
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.capability-item {
    display: flex;
    align-items: flex-start;
    gap: var(--space-md);
    padding: var(--space-md);
    border-radius: 16px;
    transition: all 0.4s var(--ease);
    border: 1px solid transparent;
}

.capability-item:hover {
    background: var(--white);
    border-color: rgba(0,0,0,0.04);
    box-shadow: 0 4px 24px rgba(0,0,0,0.03);
}

.capability-icon {
    color: var(--kiku-indigo);
    opacity: 0.6;
    flex-shrink: 0;
    margin-top: 2px;
    transition: opacity 0.4s var(--ease), color 0.4s var(--ease);
}

.capability-item:hover .capability-icon {
    opacity: 1;
    color: var(--ink);
}

.capability-text h3 {
    font-size: var(--text-base);
    font-weight: 400;
    letter-spacing: -0.01em;
    margin-bottom: var(--space-xs);
}

.capability-text p {
    font-size: var(--text-sm);
    color: var(--stone);
    line-height: 1.65;
}

/* Compatibility strip */
.compat-strip {
    text-align: center;
    max-width: 720px;
    margin: 0 auto;
    padding-top: var(--space-lg);
    border-top: 1px solid rgba(0,0,0,0.04);
}

.compat-label {
    font-size: var(--text-sm);
    color: var(--stone);
    font-weight: 400;
    margin-bottom: var(--space-sm);
    letter-spacing: -0.01em;
}

.compat-apps {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.5rem;
    margin-bottom: var(--space-sm);
}

.compat-apps span {
    font-size: var(--text-xs);
    font-weight: 400;
    color: var(--stone);
    background: rgba(74, 81, 112, 0.04);
    padding: 0.3rem 0.8rem;
    border-radius: 100px;
    letter-spacing: 0.01em;
}

.compat-note {
    font-size: var(--text-xs);
    color: var(--mist);
    font-style: italic;
}

/* ==============================
   Legal pages
   ============================== */
.legal-page {
    padding: 8rem 0 var(--space-xl);
    position: relative;
    z-index: 1;
}

.legal-content {
    max-width: 680px;
    margin: 0 auto;
}

.legal-content h1 {
    font-size: var(--text-3xl);
    font-weight: 200;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-xs);
}

.legal-updated {
    font-size: var(--text-sm);
    color: var(--mist);
    margin-bottom: var(--space-xl);
}

.legal-content h2 {
    font-size: var(--text-xl);
    font-weight: 400;
    letter-spacing: -0.01em;
    margin-top: var(--space-lg);
    margin-bottom: var(--space-sm);
}

.legal-content h3 {
    font-size: var(--text-base);
    font-weight: 400;
    margin-top: var(--space-md);
    margin-bottom: var(--space-xs);
}

.legal-content p {
    font-size: var(--text-sm);
    color: var(--ink-soft);
    line-height: 1.75;
    margin-bottom: var(--space-sm);
}

.legal-content a {
    color: var(--kiku-indigo);
    text-decoration: underline;
    text-decoration-color: rgba(74, 81, 112, 0.3);
    text-underline-offset: 2px;
    transition: text-decoration-color 0.2s var(--ease);
}

.legal-content a:hover {
    text-decoration-color: var(--kiku-indigo);
}

.legal-content ul,
.legal-content ol {
    font-size: var(--text-sm);
    color: var(--ink-soft);
    line-height: 1.75;
    margin-bottom: var(--space-sm);
    padding-left: 1.5rem;
}

.legal-content li {
    margin-bottom: 0.4rem;
}

.legal-content strong {
    font-weight: 500;
    color: var(--ink);
}

.legal-content code {
    font-size: 0.8rem;
    background: rgba(74, 81, 112, 0.06);
    padding: 0.15rem 0.5rem;
    border-radius: 4px;
    font-family: 'SF Mono', 'Fira Code', monospace;
}

.privacy-highlight {
    background: rgba(74, 81, 112, 0.03);
    border-left: 3px solid var(--kiku-indigo);
    padding: var(--space-md);
    border-radius: 0 12px 12px 0;
    margin-bottom: var(--space-lg);
}

.privacy-highlight p {
    font-size: var(--text-base);
    color: var(--ink-soft);
    line-height: 1.7;
    margin-bottom: 0;
}

/* Data controls table */
.data-table {
    margin: var(--space-sm) 0 var(--space-md);
    border: 1px solid rgba(0,0,0,0.06);
    border-radius: 12px;
    overflow: hidden;
}

.data-row {
    display: flex;
    gap: var(--space-md);
    padding: 0.8rem var(--space-sm);
    font-size: var(--text-sm);
    border-bottom: 1px solid rgba(0,0,0,0.04);
}

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

.data-row:nth-child(even) {
    background: rgba(74, 81, 112, 0.015);
}

.data-type {
    flex: 0 0 160px;
    font-weight: 500;
    color: var(--ink);
}

.data-location {
    color: var(--stone);
    line-height: 1.5;
}

/* ==============================
   Footer (updated)
   ============================== */
.footer-grid {
    display: grid;
    grid-template-columns: 1fr auto auto;
    gap: var(--space-lg);
    padding-bottom: var(--space-md);
}

.footer-brand-col {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.footer-tagline {
    font-size: var(--text-xs);
    color: var(--mist);
}

.footer-links-col h4 {
    font-size: var(--text-xs);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--stone);
    margin-bottom: 0.6rem;
}

.footer-links-col ul {
    list-style: none;
    padding: 0;
}

.footer-links-col li {
    margin-bottom: 0.35rem;
}

.footer-links-col a {
    font-size: var(--text-sm);
    color: var(--mist);
    transition: color 0.2s var(--ease);
}

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

.footer-social-col h4 {
    font-size: var(--text-xs);
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--stone);
    margin-bottom: 0.6rem;
}

.social-icons {
    display: flex;
    gap: 0.75rem;
}

.social-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 8px;
    color: var(--mist);
    transition: color 0.2s var(--ease), background 0.2s var(--ease);
}

.social-icon:hover {
    color: var(--ink);
    background: rgba(0,0,0,0.04);
}

.footer-bottom {
    border-top: 1px solid rgba(0,0,0,0.04);
    padding-top: var(--space-md);
}

/* ==============================
   Animations
   ============================== */

/* Fade-in on scroll */
.fade-in {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity 0.8s var(--ease), transform 0.8s var(--ease);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Stagger children */
.stagger > * {
    opacity: 0;
    transform: translateY(16px);
    transition: opacity 0.6s var(--ease), transform 0.6s var(--ease);
}

.stagger.visible > *:nth-child(1) { transition-delay: 0s; }
.stagger.visible > *:nth-child(2) { transition-delay: 0.08s; }
.stagger.visible > *:nth-child(3) { transition-delay: 0.16s; }
.stagger.visible > *:nth-child(4) { transition-delay: 0.24s; }
.stagger.visible > *:nth-child(5) { transition-delay: 0.32s; }
.stagger.visible > *:nth-child(6) { transition-delay: 0.40s; }

.stagger.visible > * {
    opacity: 1;
    transform: translateY(0);
}

/* (ripple animation defined in Hero section) */

/* ==============================
   Responsive
   ============================== */

@media (max-width: 768px) {
    :root {
        --text-4xl: 2.5rem;
        --text-3xl: 2rem;
        --text-2xl: 1.5rem;
    }

    .hero {
        padding: 8rem var(--space-sm) var(--space-lg);
        min-height: auto;
    }

    .enso-container {
        width: 280px;
        height: 280px;
    }

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

    .feature-card {
        padding: var(--space-sm) var(--space-md);
    }

    .steps {
        flex-direction: column;
        align-items: center;
        gap: var(--space-md);
    }


    .step {
        padding: 0;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: var(--space-md);
        text-align: center;
    }

    .footer-links-col ul {
        display: flex;
        justify-content: center;
        gap: var(--space-sm);
        flex-wrap: wrap;
    }

    .footer-links-col li {
        margin-bottom: 0;
    }

    .privacy-content,
    .philosophy-text {
        padding: 0 var(--space-sm);
    }

    .capability-item {
        flex-direction: column;
        text-align: center;
        align-items: center;
    }

    .data-row {
        flex-direction: column;
        gap: 0.2rem;
    }

    .data-type {
        flex: none;
    }

    .legal-page {
        padding-top: 6rem;
    }
}

@media (max-width: 480px) {
    :root {
        --text-4xl: 2rem;
        --text-3xl: 1.75rem;
    }

    .hero h1 {
        font-size: var(--text-3xl);
    }

    .hero-sub {
        font-size: var(--text-base);
    }

    .hero-actions {
        flex-direction: column;
    }
}

/* ---- Selection color ---- */
::selection {
    background: rgba(74, 81, 112, 0.15);
}

/* ---- Smooth scrollbar ---- */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--cloud);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--mist);
}