* { box-sizing: border-box; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    color: #1f2937;
}

.navbar {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    padding: 16px 24px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-left {
    display: flex;
    align-items: center;
    gap: 16px;
}

.logo {
    font-size: 24px;
    font-weight: 700;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.back-btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 16px;
    background: white;
    border: 1px solid #e5e7eb;
    border-radius: 8px;
    text-decoration: none;
    color: #374151;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
}

.back-btn:hover {
    background: #f9fafb;
    border-color: #d1d5db;
    transform: translateX(-2px);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 60px 24px;
}

.header {
    text-align: center;
    margin-bottom: 48px;
    color: white;
}

.header h1 {
    font-size: 42px;
    font-weight: 700;
    margin: 0 0 16px 0;
    text-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header p {
    font-size: 18px;
    opacity: 0.95;
    margin: 0;
}

.plans {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 24px;
    margin-bottom: 40px;
}

.plan {
    background: white;
    border-radius: 16px;
    padding: 32px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.plan::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
}

.plan:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 60px rgba(0,0,0,0.15);
}

.plan h3 {
    font-size: 24px;
    font-weight: 700;
    margin: 0 0 12px 0;
    color: #111827;
}

.current-plan-text {
    display: inline-block;
    padding: 12px 24px;
    color: #666;
    font-weight: 600;
    font-size: 16px;
    text-align: center;
    border: solid black 1px;
    border-radius: 10px;
}

.price {
    font-size: 36px;
    font-weight: 700;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin: 16px 0;
}

.price-unit {
    font-size: 16px;
    color: #6b7280;
    font-weight: 400;
}

.desc {
    font-size: 15px;
    color: #6b7280;
    line-height: 1.6;
    margin: 16px 0 24px 0;
    min-height: 48px;
}

.features {
    background: #f9fafb;
    border-radius: 12px;
    padding: 16px;
    margin: 20px 0;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 14px;
    color: #374151;
    margin: 8px 0;
}

.feature-icon {
    color: #10b981;
    font-weight: 700;
}

.cta {
    margin-top: 24px;
}

.btn {
    display: block;
    width: 100%;
    text-align: center;
    padding: 14px 24px;
    border-radius: 10px;
    text-decoration: none;
    font-size: 16px;
    font-weight: 600;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(102, 126, 234, 0.5);
}

.loading {
    text-align: center;
    padding: 60px;
    color: white;
    font-size: 18px;
    grid-column: 1 / -1;
}

.error {
    grid-column: 1 / -1;
    color: #dc2626;
    text-align: center;
    padding: 32px;
    background: white;
    border-radius: 16px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
}

.error strong {
    display: block;
    font-size: 20px;
    margin-bottom: 12px;
}

footer {
    text-align: center;
    margin-top: 40px;
    color: white;
    opacity: 0.9;
}

footer small {
    font-size: 14px;
}

@media (max-width: 768px) {
    .header h1 {
        font-size: 32px;
    }

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

    .navbar {
        flex-direction: column;
        gap: 12px;
    }
}