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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: #f8f5f0;
    color: #333;
    max-width: 414px;
    margin: 0 auto;
}

.top-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #8b4513;
    padding: 12px 16px;
    position: sticky;
    top: 0;
    z-index: 100;
}

.top-nav .logo {
    color: #fff;
    font-size: 18px;
    font-weight: bold;
}

.top-nav nav {
    display: flex;
    gap: 8px;
}

.top-nav nav a {
    color: #fff;
    text-decoration: none;
    font-size: 12px;
    padding: 6px 8px;
    border-radius: 4px;
}

.top-nav nav a:hover {
    background: rgba(255,255,255,0.2);
}

.top-nav nav a.active {
    background: #d2691e;
}

.container {
    padding: 16px;
    background: #f8f5f0;
}

.screen {
    background: #fff;
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 16px;
}

.invite-header {
    padding: 0;
    overflow: hidden;
}

.invite-banner {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 24px 16px;
    text-align: center;
}

.banner-title {
    color: #fff;
    font-size: 22px;
    font-weight: bold;
    margin-bottom: 8px;
}

.banner-desc {
    color: rgba(255,255,255,0.9);
    font-size: 14px;
}

.subtitle {
    font-size: 16px;
    font-weight: bold;
    color: #333;
    margin-bottom: 12px;
}

.rewards-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.reward-item {
    display: flex;
    align-items: center;
    gap: 12px;
    background: #f8f5f0;
    border-radius: 8px;
    padding: 12px;
}

.reward-icon {
    font-size: 32px;
}

.reward-info {
    flex: 1;
}

.reward-title {
    font-size: 14px;
    font-weight: bold;
    color: #333;
    margin-bottom: 4px;
}

.reward-desc {
    font-size: 12px;
    color: #666;
}

.invite-code-box {
    display: flex;
    gap: 12px;
    align-items: center;
    background: #f8f5f0;
    border-radius: 8px;
    padding: 12px;
}

.invite-code {
    flex: 1;
    font-size: 20px;
    font-weight: bold;
    color: #8b4513;
    letter-spacing: 2px;
    text-align: center;
}

.copy-btn {
    background: #d2691e;
    color: #fff;
    border: none;
    padding: 10px 16px;
    border-radius: 6px;
    font-size: 14px;
    cursor: pointer;
}

.copy-btn:hover {
    background: #b85919;
}

.code-tip {
    font-size: 12px;
    color: #999;
    text-align: center;
    margin-top: 8px;
}

.share-link-box {
    display: flex;
    gap: 12px;
    align-items: center;
    background: #f8f5f0;
    border-radius: 8px;
    padding: 12px;
}

.share-link {
    flex: 1;
    border: none;
    background: transparent;
    font-size: 12px;
    color: #666;
}

.share-methods {
    display: flex;
    gap: 12px;
    margin-top: 16px;
}

.share-btn {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
    padding: 16px 8px;
    border: 1px solid #eee;
    border-radius: 8px;
    background: #fff;
    cursor: pointer;
}

.share-btn:hover {
    border-color: #d2691e;
}

.share-icon {
    font-size: 24px;
}

.share-btn span:last-child {
    font-size: 12px;
    color: #666;
}

.stats-grid {
    display: flex;
    gap: 12px;
}

.stat-item {
    flex: 1;
    text-align: center;
    padding: 16px 8px;
    background: #f8f5f0;
    border-radius: 8px;
}

.stat-number {
    font-size: 24px;
    font-weight: bold;
    color: #8b4513;
    margin-bottom: 4px;
}

.stat-label {
    font-size: 12px;
    color: #666;
}

.invite-list {
    min-height: 120px;
}

.empty-state {
    text-align: center;
    padding: 32px 16px;
}

.empty-icon {
    font-size: 48px;
    margin-bottom: 12px;
}

.empty-text {
    font-size: 14px;
    color: #666;
    margin-bottom: 4px;
}

.empty-desc {
    font-size: 12px;
    color: #999;
}

#float-btn {
    position: fixed;
    bottom: 24px;
    right: 24px;
    background: #8b4513;
    color: #fff;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    text-align: center;
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
    cursor: pointer;
    z-index: 1000;
}

#float-btn:hover {
    background: #6d3610;
}