:root {
    --primary-color: #0b5cff;
    --primary-hover: #0046d1;
    --text-main: #2d3748;
    --text-muted: #718096;
    --bg-light: #f7fafc;
    --bg-dark: #1a202c;
    --white: #ffffff;
    --border-color: #e2e8f0;
    --font-sans: 'Inter', 'Noto Sans JP', sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    color: var(--text-main);
    line-height: 1.6;
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: color 0.3s ease;
}

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

.container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Header */
.header {
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid var(--border-color);
    padding: 16px 0;
}

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

.logo {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--text-main);
    letter-spacing: -0.5px;
}

.nav {
    display: flex;
    gap: 24px;
    align-items: center;
}

.nav a {
    color: var(--text-main);
    font-weight: 500;
    font-size: 0.95rem;
}

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

.lang-switch {
    display: inline-block;
    padding: 6px 12px;
    border: 1px solid var(--border-color);
    border-radius: 20px;
    font-size: 0.85rem !important;
}

.lang-switch:hover {
    background-color: var(--bg-light);
}

/* Hero Section */
.hero {
    padding: 100px 0 80px;
    text-align: center;
    background: linear-gradient(135deg, var(--bg-light) 0%, var(--white) 100%);
}

.hero-title {
    font-size: 3rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 24px;
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto 48px;
    line-height: 1.8;
}

.download-card {
    background: var(--white);
    padding: 32px;
    border-radius: 16px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    display: inline-block;
    border: 1px solid var(--border-color);
}

.btn {
    display: inline-block;
    padding: 14px 32px;
    font-size: 1.1rem;
    font-weight: 500;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    box-shadow: 0 4px 6px rgba(11, 92, 255, 0.2);
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    color: var(--white);
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(11, 92, 255, 0.3);
}

.download-stats {
    margin-top: 16px;
    font-size: 0.95rem;
    color: var(--text-muted);
}

#download-count {
    font-weight: 700;
    color: var(--text-main);
    font-size: 1.1rem;
}

/* Common Section Styles */
.section {
    padding: 80px 0;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 40px;
    text-align: center;
}

.bg-light {
    background-color: var(--bg-light);
}

.bg-dark {
    background-color: var(--bg-dark);
}

.text-white {
    color: var(--white);
}

/* Manual Section */
.manual-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 32px;
}

.step-card {
    background: var(--white);
    padding: 32px;
    border-radius: 12px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.02);
    border: 1px solid var(--border-color);
    position: relative;
    transition: transform 0.3s ease;
}

.step-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 15px rgba(0,0,0,0.05);
}

.step-number {
    width: 48px;
    height: 48px;
    background-color: var(--primary-color);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 24px;
}

.step-title {
    font-size: 1.25rem;
    margin-bottom: 16px;
    font-weight: 700;
}

.step-card p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.7;
}

.note {
    font-size: 0.85rem !important;
    color: #a0aec0 !important;
    margin-top: 16px;
    font-weight: 500;
}

/* Developer Info Section */
.developer-info {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.dev-name {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.dev-title {
    font-size: 1.1rem;
    color: #a0aec0;
    margin-bottom: 24px;
}

.dev-desc {
    color: #cbd5e0;
    font-size: 1.05rem;
    line-height: 1.8;
}

/* Footer */
.footer {
    padding: 32px 0;
    text-align: center;
    border-top: 1px solid var(--border-color);
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* Responsive */
@media (max-width: 768px) {
    .nav {
        display: none; 
    }
    .hero-title {
        font-size: 2.25rem;
    }
    .hero-subtitle {
        font-size: 1.05rem;
    }
    .hero {
        padding: 60px 0;
    }
    .section {
        padding: 60px 0;
    }
}