/* Core brand colors */
:root {
    --color-aviation-blue: #1e40af;
    --color-aviation-blue-light: #3b82f6;
    --color-aviation-blue-dark: #1e3a8a;
    
    --color-slate-800: #1e293b;
    --color-slate-600: #475569;
    --color-slate-400: #94a3b8;
    
    --color-off-white: #f8fafc;
    --color-white: #ffffff;
    
    --color-error: #ef4444;
    --color-success: #22c55e;
    --color-warning: #f59e0b;
    
    /* Spacing units */
    --space-1: 0.25rem;
    --space-2: 0.5rem;
    --space-3: 0.75rem;
    --space-4: 1rem;
    --space-6: 1.5rem;
    --space-8: 2rem;
    --space-12: 3rem;
    --space-16: 4rem;
}

/* Typography */
body {
    font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen-Sans, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
    font-size: 16px;
    line-height: 1.5;
    color: var(--color-slate-800);
    background: var(--color-white);
}

h1, h2, h3, h4, h5, h6 {
    font-family: Inter, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-weight: 600;
    line-height: 1.2;
    margin: 0 0 var(--space-4) 0;
    color: var(--color-slate-800);
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
}

h2 {
    font-size: 2rem;
    margin-top: var(--space-8);
}

h3 {
    font-size: 1.5rem;
    color: var(--color-aviation-blue);
}

p {
    margin: 0 0 var(--space-4) 0;
}

/* Links */
a {
    color: var(--color-aviation-blue);
    text-decoration: none;
    transition: color 0.2s ease;
}

a:hover {
    color: var(--color-aviation-blue-light);
    text-decoration: underline;
}

/* Content container */
.content-area {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-8) var(--space-4);
}

/* Section spacing */
.ppf-section {
    margin-bottom: var(--space-12);
    padding: 0;
}

.ppf-section:last-child {
    margin-bottom: 0;
}

/* Card layouts */
.ppf-card {
    background: var(--color-white);
    border: 1px solid var(--color-slate-400);
    border-radius: 8px;
    padding: var(--space-6);
    margin-bottom: var(--space-6);
    transition: box-shadow 0.2s ease;
}

.ppf-card:hover {
    box-shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

/* Form elements */
input, select, textarea {
    font-family: inherit;
    font-size: 1rem;
    line-height: 1.5;
    padding: var(--space-2) var(--space-3);
    border: 1px solid var(--color-slate-400);
    border-radius: 4px;
    background: var(--color-white);
    width: 100%;
    transition: border-color 0.2s ease;
}

input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--color-aviation-blue);
    box-shadow: 0 0 0 2px rgba(30, 64, 175, 0.1);
}

button {
    background: var(--color-aviation-blue);
    color: var(--color-white);
    border: none;
    border-radius: 4px;
    padding: var(--space-3) var(--space-6);
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

button:hover {
    background: var(--color-aviation-blue-dark);
}

/* Helper classes */
.text-center {
    text-align: center;
}

.text-muted {
    color: var(--color-slate-600);
}

.mb-0 {
    margin-bottom: 0;
}

.mt-0 {
    margin-top: 0;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    h1 {
        font-size: 2rem;
    }

    h2 {
        font-size: 1.75rem;
    }

    h3 {
        font-size: 1.25rem;
    }

    .content-area {
        padding: var(--space-6) var(--space-4);
    }

    .ppf-section {
        margin-bottom: var(--space-8);
    }
}

@media (max-width: 640px) {
    body {
        font-size: 15px;
    }

    h1 {
        font-size: 1.75rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    h3 {
        font-size: 1.25rem;
    }

    .content-area {
        padding: var(--space-4);
    }
}