:root {
    --primary-color: #4A90E2;
    --secondary-color: #5E72E4;
    --text-color: #333;
    --bg-color: #F7F9FC;
    --white: #FFFFFF;
    --spacing: 20px;
}

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

body {
    font-family: 'Noto Sans SC', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing);
}

/* Header */
header {
    background-color: var(--white);
    padding: 15px 0;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 100;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-img {
    height: 40px;
    width: auto;
}

.logo span {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--secondary-color);
}

/* Hero Section */
.hero {
    padding: 80px 0;
    background: linear-gradient(135deg, #ffffff 0%, #f0f4ff 100%);
    overflow: hidden;
}

.hero-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
}

.hero-text {
    flex: 1;
}

.hero-text h1 {
    font-size: 3.5rem;
    margin-bottom: 24px;
    color: #2c3e50;
    line-height: 1.2;
    font-weight: 800;
}

.hero-text p {
    font-size: 1.25rem;
    margin-bottom: 40px;
    color: #666;
    max-width: 500px;
}

.btn {
    display: inline-block;
    padding: 14px 40px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s ease;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    box-shadow: 0 10px 20px rgba(74, 144, 226, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 30px rgba(74, 144, 226, 0.4);
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    position: relative;
}

.hero-image img {
    max-width: 100%;
    height: auto;
    max-height: 650px;
    /* Clean shadow for app screenshot */
    filter: drop-shadow(0 20px 40px rgba(0, 0, 0, 0.15));
}

/* Section Common */
section {
    padding: 100px 0;
}

section h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 60px;
    color: #2c3e50;
    position: relative;
    display: inline-block;
    width: 100%;
}

/* Features Section */
.features {
    background-color: var(--white);
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.feature-card {
    background: #ffffff;
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid #f0f0f0;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
    border-color: transparent;
}

.feature-card .icon {
    font-size: 3rem;
    margin-bottom: 25px;
    background: linear-gradient(135deg, #eef4ff 0%, #e6f0ff 100%);
    width: 90px;
    height: 90px;
    line-height: 90px;
    border-radius: 30px;
    margin-left: auto;
    margin-right: auto;
    color: var(--primary-color);
}

.feature-card h3 {
    font-size: 1.5rem;
    margin-bottom: 15px;
    color: #333;
}

.feature-card p {
    color: #666;
    font-size: 1.05rem;
}

/* How It Works Section */
.how-it-works {
    background-color: var(--bg-color);
}

.steps-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    text-align: center;
}

.step-card {
    position: relative;
    padding: 20px;
}

.step-number {
    width: 60px;
    height: 60px;
    background-color: var(--primary-color);
    color: white;
    font-size: 1.5rem;
    font-weight: bold;
    border-radius: 50%;
    line-height: 60px;
    margin: 0 auto 20px;
    box-shadow: 0 10px 20px rgba(74, 144, 226, 0.3);
}

.step-card h3 {
    margin-bottom: 15px;
    font-size: 1.4rem;
}

.step-card p {
    color: #666;
}

/* FAQ Section */
.faq {
    background-color: var(--white);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    margin-bottom: 20px;
    border-bottom: 1px solid #eee;
    padding-bottom: 20px;
}

.faq-item:last-child {
    border-bottom: none;
}

.faq-item h3 {
    font-size: 1.25rem;
    margin-bottom: 10px;
    color: #2c3e50;
}

.faq-item p {
    color: #666;
}

/* Footer */
footer {
    background-color: #2c3e50;
    color: #ecf0f1;
    padding: 50px 0;
    text-align: center;
}

.footer-links {
    margin-bottom: 25px;
    display: flex;
    justify-content: center;
    gap: 30px;
}

.footer-links a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s;
    font-weight: 500;
}

.footer-links a:hover {
    color: var(--white);
    text-decoration: underline;
}

.copyright {
    font-size: 0.9rem;
    color: #7f8c8d;
}

/* Responsive */
@media (max-width: 900px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
        padding-top: 20px;
    }

    .hero-text h1 {
        font-size: 2.5rem;
    }

    .hero-text p {
        margin-left: auto;
        margin-right: auto;
    }

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

    .step-card {
        margin-bottom: 20px;
    }
}