:root {
    --primary-color: #333;
    --secondary-bg: #f7f7f7;
    --text-main: #1d1d1f;
    --text-sub: #86868b;
    --accent-color: #0071e3;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
    line-height: 1.4;
    color: var(--text-main);
    background-color: #fff;
    padding: 48px 20px 24px 20px;
    -webkit-font-smoothing: antialiased;
    height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 400px;
    margin: 0 auto;
    width: 100%;
}

/* Animations */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.fade-in {
    opacity: 0;
    animation: fadeInUp 0.5s ease-out forwards;
}

/* Header */
header {
    margin-bottom: 16px;
}

.main-title {
    font-size: 26px;
    font-weight: 700;
    margin-bottom: 4px;
    color: #000;
}

.subtitle {
    font-size: 15px;
    color: var(--text-sub);
}

/* Intro */
.intro {
    margin-bottom: 20px;
    font-size: 14px;
    color: #48484a;
}

/* Features */
.features {
    margin-bottom: 20px;
}

.feature-item {
    display: flex;
    align-items: center;
    margin-bottom: 12px;
    padding: 8px 12px;
    background: var(--secondary-bg);
    border-radius: 12px;
}

.feature-icon {
    font-size: 18px;
    margin-right: 12px;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.feature-content h3 {
    font-size: 15px;
    font-weight: 600;
}

.feature-content p {
    font-size: 13px;
    color: var(--text-sub);
}

/* Action Section */
.action-info .highlight {
    font-size: 14px;
    font-weight: 600;
    color: var(--accent-color);
    margin-bottom: 2px;
}

.action-info h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 16px;
}

.download-card {
    padding: 12px 16px;
    border-radius: 16px;
    margin-bottom: 12px;
    border: 1px solid #eee;
}

.download-card p {
    font-size: 13px;
    margin-bottom: 10px;
    color: #48484a;
    line-height: 1.3;
}

/* Buttons */
.btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 10px;
    border-radius: 10px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.2s;
}

.btn-icon {
    margin-right: 8px;
    width: 20px;
    height: 20px;
    object-fit: contain;
}

.btn-primary {
    background-color: #000;
    color: #fff;
}

.btn-secondary {
    background-color: var(--secondary-bg);
    color: #000;
}

@media (max-height: 600px) {
    body { padding: 16px; }
    header { margin-bottom: 10px; }
    .features { margin-bottom: 10px; }
    .feature-item { margin-bottom: 8px; }
}