* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-family);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
    margin: 0 0 var(--space-2) 0;
    line-height: 1.25;
}

p {
    margin: 0 0 var(--space-3) 0;
}

a {
    color: var(--color-brand-600);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

img {
    max-width: 100%;
    display: block;
}

.app-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-3) var(--space-5);
    background: var(--color-white);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 20;
}

.app-nav-brand {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-weight: 700;
    font-size: 1.1rem;
    color: var(--color-brand-700);
}

.app-nav-logo {
    width: 28px;
    height: 28px;
    flex-shrink: 0;
}

.app-nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    font-size: 0.9rem;
}

.app-nav-user {
    color: var(--color-text-muted);
}

.container {
    max-width: 480px;
    margin: 0 auto;
    padding: var(--space-5) var(--space-4) var(--space-8);
}

.container-wide {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--space-5) var(--space-4) var(--space-8);
}

@media (min-width: 700px) {
    .container {
        padding-top: var(--space-8);
    }
}