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

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #f1f5f9;
    --text-color: #1e293b;
    --text-light: #64748b;
    --white: #ffffff;
    --gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);
}

body {
    font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text-color);
    line-height: 1.6;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    border-bottom: 1px solid rgba(0, 0, 0, 0.05);
}

.nav {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.75rem;
    font-weight: 700;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.2s;
}

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

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 8rem 2rem 4rem;
    background: linear-gradient(180deg, #f8fafc 0%, #ffffff 100%);
}

.hero-container {
    max-width: 1200px;
    width: 100%;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 4rem;
}

.hero-content {
    flex: 1;
    max-width: 550px;
}

.hero-title {
    font-size: 3.25rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: 1.5rem;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: var(--text-light);
    margin-bottom: 2.5rem;
    line-height: 1.8;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 1rem 2rem;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    transition: all 0.2s;
}

.btn-primary {
    background: var(--gradient);
    color: var(--white);
    box-shadow: 0 4px 14px rgba(99, 102, 241, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
}

.btn-secondary {
    background: var(--secondary-color);
    color: var(--text-color);
}

.btn-secondary:hover {
    background: #e2e8f0;
}

.hero-visual {
    flex-shrink: 0;
    display: flex;
    justify-content: center;
    align-items: center;
}

.phone-mockup {
    width: 280px;
    height: 560px;
    background: var(--text-color);
    border-radius: 40px;
    padding: 12px;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.15);
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: var(--white);
    border-radius: 32px;
    padding: 2rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.chat-bubble {
    padding: 1rem 1.25rem;
    border-radius: 18px;
    max-width: 85%;
    font-size: 0.9rem;
    line-height: 1.5;
}

.chat-bubble.ai {
    background: var(--secondary-color);
    align-self: flex-start;
    border-bottom-left-radius: 4px;
}

.chat-bubble.user {
    background: var(--gradient);
    color: var(--white);
    align-self: flex-end;
    border-bottom-right-radius: 4px;
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
}

.features {
    padding: 6rem 2rem;
    background: var(--white);
}

.feature-grid {
    max-width: 900px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2rem;
}

.feature-card {
    background: var(--secondary-color);
    padding: 2rem;
    border-radius: 20px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 30px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    width: 56px;
    height: 56px;
    background: var(--gradient);
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.feature-icon svg {
    width: 28px;
    height: 28px;
    color: var(--white);
}

.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
}

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

.how-it-works {
    padding: 6rem 2rem;
    background: linear-gradient(180deg, #f8fafc 0%, #ffffff 100%);
}

.steps {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: flex-start;
    justify-content: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.step {
    flex: 1;
    min-width: 200px;
    max-width: 250px;
    text-align: center;
    padding: 1.5rem;
}

.step-number {
    width: 48px;
    height: 48px;
    background: var(--gradient);
    color: var(--white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 700;
    margin: 0 auto 1rem;
}

.step h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.step p {
    color: var(--text-light);
    font-size: 0.9rem;
}

.step-arrow {
    color: var(--primary-color);
    font-size: 1.5rem;
    font-weight: 300;
    align-self: center;
    margin-top: -1rem;
}

.download {
    padding: 6rem 2rem;
    background: var(--gradient);
    text-align: center;
}

.download .section-title {
    color: var(--white);
}

.download-subtitle {
    color: rgba(255, 255, 255, 0.85);
    font-size: 1.1rem;
    margin-bottom: 2.5rem;
}

.download-buttons {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    flex-wrap: wrap;
}

.store-btn {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: var(--text-color);
    color: var(--white);
    padding: 0.875rem 1.5rem;
    border-radius: 12px;
    text-decoration: none;
    transition: transform 0.2s, box-shadow 0.2s;
}

.store-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

.store-btn svg {
    width: 32px;
    height: 32px;
}

.store-text {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.store-label {
    font-size: 0.65rem;
    opacity: 0.9;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.store-name {
    font-size: 1.1rem;
    font-weight: 600;
}

.footer {
    padding: 3rem 2rem;
    background: var(--text-color);
    color: var(--white);
    text-align: center;
}

.footer-logo {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.footer-text {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.footer-copyright {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.85rem;
}

@media (max-width: 768px) {
    .hero {
        padding-top: 8rem;
    }

    .hero-container {
        flex-direction: column;
        text-align: center;
        gap: 3rem;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-title {
        font-size: 2rem;
        margin-top: 1rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .hero-buttons {
        justify-content: center;
    }

    .phone-mockup {
        width: 240px;
        height: 480px;
    }

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

    .step-arrow {
        display: none;
    }

    .steps {
        flex-direction: column;
        align-items: center;
    }

    .step {
        max-width: 100%;
    }

    .nav-links {
        display: none;
    }

    .section-title {
        font-size: 2rem;
    }
}