/* ===== CSS Variables ===== */
:root {
    --bg-primary: #ffffff;
    --bg-card: #ffffff;
    --text-primary: #000000;
    --text-secondary: #444444;
    --text-muted: #666666;
    --accent: #000000;
    --border: #000000;
    --transition: 0.15s ease;
    --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

a {
    color: inherit;
    text-decoration: none;
    transition: opacity var(--transition);
}

a:hover {
    opacity: 0.6;
}

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

/* ===== Typography ===== */
h1,
h2,
h3 {
    font-weight: 600;
    line-height: 1.2;
}

h1 {
    font-size: clamp(2.5rem, 6vw, 4rem);
    letter-spacing: -0.03em;
}

h2 {
    font-size: clamp(1.5rem, 3vw, 2rem);
    letter-spacing: -0.02em;
}

h3 {
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

p {
    color: var(--text-secondary);
}

/* ===== Layout ===== */
.container {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding: 0 2rem;
}

/* ===== Header ===== */
.header {
    padding: 1.5rem 0;
    border-bottom: 2px solid var(--border);
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 0.875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    width: 20px;
    height: 20px;
    background: var(--accent);
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav a {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-secondary);
}

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

/* ===== Hero ===== */
.hero {
    padding: 8rem 0 6rem;
    text-align: left;
}

.hero-badge {
    display: inline-block;
    padding: 0.5rem 0;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--text-muted);
    margin-bottom: 2rem;
    border-bottom: 1px solid var(--border);
}

.hero h1 {
    margin-bottom: 1.5rem;
}

.hero-gradient {
    text-decoration: underline;
    text-decoration-thickness: 3px;
    text-underline-offset: 6px;
}

.hero>.container>p {
    max-width: 400px;
    font-size: 1rem;
    margin-bottom: 0;
}

/* ===== App Card ===== */
.app-card {
    display: block;
    background: var(--bg-card);
    border: 2px solid var(--border);
    padding: 2rem;
    max-width: 350px;
    margin: 4rem 0 0;
    transition: background var(--transition);
}

.app-card:hover {
    background: #f5f5f5;
    opacity: 1;
}

.app-icon {
    width: 48px;
    height: 48px;
    background: var(--accent);
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    color: var(--bg-primary);
}

.app-card h3 {
    margin-bottom: 0.75rem;
    font-size: 1.125rem;
    text-transform: none;
    letter-spacing: -0.01em;
}

.app-card p {
    font-size: 0.875rem;
    margin-bottom: 1.5rem;
}

.app-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-weight: 500;
}

.app-link svg {
    transition: transform var(--transition);
}

.app-link:hover svg {
    transform: translateX(4px);
}

/* ===== Features Section ===== */
.features {
    padding: 4rem 0;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1px;
    background: var(--border);
    border: 2px solid var(--border);
}

.feature {
    background: var(--bg-card);
    padding: 1.5rem;
}

.feature-icon {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.feature h3 {
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
}

.feature p {
    font-size: 0.8125rem;
}

/* ===== App Page ===== */
.app-hero {
    padding: 4rem 0;
    text-align: left;
}

.app-hero .app-icon {
    width: 64px;
    height: 64px;
    margin: 0 0 1.5rem;
    font-size: 1.75rem;
}

.app-hero p {
    max-width: 500px;
}

.app-description {
    padding: 0 0 4rem;
}

.description-card {
    background: var(--bg-card);
    border: 2px solid var(--border);
    padding: 2rem;
}

.description-card h2 {
    margin-bottom: 1rem;
    font-size: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.description-card p {
    margin-bottom: 1rem;
}

.description-card ul {
    list-style: none;
    margin-top: 1rem;
}

.description-card li {
    position: relative;
    padding-left: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9375rem;
}

.description-card li::before {
    content: '→';
    position: absolute;
    left: 0;
    color: var(--accent);
}

/* ===== Privacy Page ===== */
.privacy {
    padding: 4rem 0;
}

.privacy h1 {
    margin-bottom: 0.5rem;
    font-size: clamp(1.5rem, 4vw, 2rem);
}

.privacy-date {
    color: var(--text-muted);
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 3rem;
}

.privacy-content {
    max-width: 600px;
}

.privacy-content h2 {
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin: 3rem 0 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border);
    color: var(--text-primary);
}

.privacy-content h3 {
    font-size: 0.875rem;
    margin: 1.5rem 0 0.75rem;
    color: var(--text-secondary);
    text-transform: none;
    letter-spacing: 0;
}

.privacy-content p {
    margin-bottom: 1rem;
    font-size: 0.9375rem;
}

.privacy-content ul {
    list-style: none;
    margin: 1rem 0;
}

.privacy-content li {
    position: relative;
    padding-left: 1.25rem;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
    font-size: 0.9375rem;
}

.privacy-content li::before {
    content: '—';
    position: absolute;
    left: 0;
    color: var(--accent);
}

.contact-email {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 500;
    text-decoration: underline;
}

/* ===== Footer ===== */
.footer {
    padding: 2rem 0;
    border-top: 2px solid var(--border);
}

.footer p {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

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

/* ===== Responsive ===== */
@media (max-width: 640px) {
    .hero {
        padding: 5rem 0 4rem;
    }

    .nav {
        gap: 1.25rem;
    }

    .app-card {
        margin: 3rem 0 0;
        max-width: 100%;
    }
}