@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
    --bg-base: #0f172a;
    --bg-surface: rgba(30, 41, 59, 0.7);
    --bg-card: rgba(30, 41, 59, 0.9);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-primary: #3b82f6;
    --accent-hover: #2563eb;
    --border-color: rgba(255, 255, 255, 0.1);
    --success: #10b981;
    --danger: #ef4444;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-base);
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background-image: 
        radial-gradient(circle at 15% 50%, rgba(59, 130, 246, 0.15), transparent 25%),
        radial-gradient(circle at 85% 30%, rgba(139, 92, 246, 0.15), transparent 25%);
    background-attachment: fixed;
}

a {
    color: var(--accent-primary);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--text-primary);
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.5rem 5%;
    background: var(--bg-surface);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-brand {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    text-transform: uppercase;
    letter-spacing: 1px;
}

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

.nav-links a {
    color: var(--text-secondary);
    font-weight: 500;
}

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

.btn {
    padding: 0.75rem 1.5rem;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    display: inline-block;
}

.btn-primary {
    background: var(--accent-primary);
    color: #fff;
    box-shadow: 0 4px 14px rgba(59, 130, 246, 0.4);
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.6);
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.05);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 5%;
    flex: 1;
}

.hero {
    text-align: center;
    padding: 4rem 0;
}

.hero h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(to right, #fff, #94a3b8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto 2rem;
}

.tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
}

.tab {
    padding: 0.75rem 2rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: 30px;
    cursor: pointer;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.tab.active {
    background: var(--accent-primary);
    color: #fff;
    border-color: var(--accent-primary);
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 2rem;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    backdrop-filter: blur(10px);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
    border-color: rgba(255, 255, 255, 0.2);
}

.card-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.card-price {
    font-size: 2.5rem;
    font-weight: 700;
    margin: 1.5rem 0;
    color: var(--accent-primary);
}

.card-price span {
    font-size: 1rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.features {
    list-style: none;
    margin-bottom: 2rem;
}

.features li {
    margin-bottom: 0.75rem;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.features li::before {
    content: "✓";
    color: var(--success);
    font-weight: bold;
}

.input-group {
    margin-bottom: 1.5rem;
}

.input-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.input-group input, .input-group select {
    width: 100%;
    padding: 0.75rem 1rem;
    border-radius: 8px;
    background: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    font-size: 1rem;
    transition: border-color 0.3s;
}

.input-group input:focus, .input-group select:focus {
    outline: none;
    border-color: var(--accent-primary);
}

.auth-card {
    max-width: 400px;
    margin: 4rem auto;
}

.checkout-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 2rem;
}

.summary-card {
    position: sticky;
    top: 100px;
}

.item-row {
    display: flex;
    justify-content: space-between;
    padding: 1rem 0;
    border-bottom: 1px solid var(--border-color);
}

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

.total-row {
    display: flex;
    justify-content: space-between;
    padding-top: 1rem;
    margin-top: 1rem;
    border-top: 2px solid var(--border-color);
    font-size: 1.25rem;
    font-weight: bold;
}

@media (max-width: 768px) {
    .checkout-grid {
        grid-template-columns: 1fr;
    }
    .hero h1 {
        font-size: 2.5rem;
    }
}