:root {
    --c-bg:            #fff;
    --c-bg-navbar:     #fff;
    --c-navbar-border: #f0f0f0;
    --c-text:          #333;
    --c-text-muted:    #888;
    --c-error:         #b3261e;
    --c-cart-filter:   none;
}

@media (prefers-color-scheme: dark) {
    :root {
        --c-bg:            #222;
        --c-bg-navbar:     #1a1a1a;
        --c-navbar-border: rgba(255,255,255,0.1);
        --c-text:          #eee;
        --c-text-muted:    #888;
        --c-error:         #e06c6c;
        --c-cart-filter:   invert(1);
    }
}

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

body {
    font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif;
    color: var(--c-text);
    line-height: 1.6;
    background-color: var(--c-bg);
}

.navbar {
    width: 100%;
    display: flex;
    justify-content: flex-end;
    padding: 20px 40px;
    background-color: var(--c-bg-navbar);
    border-bottom: 1px solid var(--c-navbar-border);
}

.navbar a {
    color: var(--c-text);
    text-decoration: none;
    margin-left: 30px;
    font-weight: 500;
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: opacity 0.3s;
}

.navbar a:hover {
    opacity: 0.6;
    text-decoration: underline;
}

.checkout-header {
    max-width: 720px;
    margin: 0 auto;
    padding: 40px 20px 0;
    text-align: center;
}

.checkout-header h1 {
    font-size: 2rem;
    font-weight: 700;
    letter-spacing: -1px;
    margin-bottom: 6px;
}

.checkout-header p {
    color: var(--c-text-muted);
    font-size: 1rem;
}

#checkout {
    max-width: 720px;
    margin: 20px auto 60px;
    padding: 0 20px;
}

#checkout-error {
    max-width: 720px;
    margin: 40px auto;
    padding: 20px;
    text-align: center;
    color: var(--c-error);
}

.cart-icon { filter: var(--c-cart-filter); }