/* ==========================================================================
   TheBookFlight Premium Design System Tokens (Phase 2)
   ========================================================================== */

:root {
    /* 1. Color Palette: Deep navy, premium blue, white, soft grey */
    --color-primary-navy: #082938;
    --color-primary-blue: #0052cc;
    --color-primary-blue-hover: #003d99;
    --color-accent-red: var(--accent-primary); /* Retained from v1 brand for contrast */
    
    --color-surface-white: #ffffff;
    --color-surface-offwhite: #f8f9fa;
    --color-surface-grey: #f0f2f5;
    
    --color-text-main: #1a1a1a;
    --color-text-secondary: #5e6c84;
    --color-text-inverse: #ffffff;
    
    --color-border: #dfe1e6;
    --color-success: #0b875b;
    --color-warning: #ff991f;
    --color-error: #de350b;

    /* 2. Spacing System: 8-point grid */
    --spacing-1: 8px;
    --spacing-2: 16px;
    --spacing-3: 24px;
    --spacing-4: 32px;
    --spacing-5: 40px;
    --spacing-6: 48px;
    --spacing-8: 64px;
    --spacing-10: 80px;

    /* 3. Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px; /* 16-20 for consumer surfaces */
    --radius-xl: 20px;
    --radius-round: 9999px;

    /* 4. Shadows (Neumorphism-inspired soft depth, used sparingly) */
    --shadow-soft: 6px 6px 12px rgba(0, 0, 0, 0.04), -6px -6px 12px rgba(255, 255, 255, 0.8);
    --shadow-card: 0 4px 12px rgba(8, 41, 56, 0.08);
    --shadow-dropdown: 0 8px 24px rgba(8, 41, 56, 0.12);
    --shadow-focus: 0 0 0 3px rgba(0, 82, 204, 0.2);

    /* 5. Typography */
    --font-family-base: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    
    --font-size-xs: 12px;
    --font-size-sm: 14px;
    --font-size-base: 16px;
    --font-size-lg: 18px;
    --font-size-xl: 24px;
    --font-size-2xl: 32px;
    --font-size-3xl: 48px;

    --font-weight-regular: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    /* 6. Motion / Transitions */
    --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ==========================================================================
   Component Base Classes
   ========================================================================== */

/* Buttons */
.tbf-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-1) var(--spacing-3);
    border-radius: var(--radius-sm);
    font-family: var(--font-family-base);
    font-weight: var(--font-weight-semibold);
    font-size: var(--font-size-base);
    cursor: pointer;
    transition: all var(--transition-fast);
    border: 2px solid transparent;
}

.tbf-btn-primary {
    background-color: var(--color-primary-blue);
    color: var(--color-text-inverse);
}

.tbf-btn-primary:hover {
    background-color: var(--color-primary-blue-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 8px rgba(0, 82, 204, 0.2);
}

.tbf-btn-secondary {
    background-color: transparent;
    color: var(--color-primary-navy);
    border-color: var(--color-border);
}

.tbf-btn-secondary:hover {
    background-color: var(--color-surface-grey);
    border-color: var(--color-text-secondary);
}

/* Consumer Cards (Neumorphic) */
.tbf-card-premium {
    background-color: var(--color-surface-white);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-soft);
    padding: var(--spacing-3);
    border: 1px solid rgba(255, 255, 255, 0.5);
}

/* Data-dense Cards (Crisp, no blur) */
.tbf-card-data {
    background-color: var(--color-surface-white);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-card);
    border: 1px solid var(--color-border);
    padding: var(--spacing-2);
}

/* Skeleton Loader */
@keyframes shimmer {
    0% { background-position: -1000px 0; }
    100% { background-position: 1000px 0; }
}

.tbf-skeleton {
    background: var(--color-surface-grey);
    background-image: linear-gradient(90deg, var(--color-surface-grey) 0px, var(--color-surface-white) 50%, var(--color-surface-grey) 100%);
    background-size: 1000px 100%;
    animation: shimmer 2s infinite linear;
    border-radius: var(--radius-sm);
}