body {
    background-color: var(--color-bg-primary);
    color: var(--color-text-primary);
    min-height: 100vh;
}

#app {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* Header */
.app-header {
    height: var(--header-height);
    background-color: var(--color-bg-secondary);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.app-title {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-success) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Navigation */
nav {
    background-color: var(--color-bg-secondary);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: var(--header-height);
    z-index: 99;
}

/* Main content */
.app-main {
    flex: 1;
    max-width: var(--max-width);
    width: 100%;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn var(--transition-base);
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Grid layouts */
.grid {
    display: grid;
    gap: var(--spacing-lg);
}

.grid-auto {
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
}

.grid-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
    grid-template-columns: repeat(3, 1fr);
}

/* Flex utilities */
.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.items-center {
    align-items: center;
}

.justify-between {
    justify-content: space-between;
}

.justify-center {
    justify-content: center;
}

.gap-sm {
    gap: var(--spacing-sm);
}

.gap-md {
    gap: var(--spacing-md);
}

.gap-lg {
    gap: var(--spacing-lg);
}

/* Responsive */
@media (max-width: 1024px) {
    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .app-main {
        padding: var(--spacing-lg) var(--spacing-md);
    }

    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
    }

    .header-content {
        padding: 0 var(--spacing-md);
    }

    .app-title {
        font-size: var(--font-size-xl);
    }

    .header-actions {
        gap: var(--spacing-sm);
    }
}