:root {
    --color-primary: #0055a4;
    --color-secondary: #ffd700;
    --color-background: #ffffff;
    --color-text: #333333;
    --color-link: #0055a4;
    --color-error: #d32f2f;
    --color-success: #388e3c;
    --color-border: #cccccc;
    --color-header: #f5f5f5;
}

* {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    margin: 0;
    padding: 0;
    color: var(--color-text);
    background-color: var(--color-background);
    line-height: 1.6;
}

/* Header */
header {
    background-color: var(--color-header);
    padding: 1rem;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.brand h1 {
    margin: 0;
    font-size: 1.5rem;
    color: var(--color-primary);
}

.brand p {
    margin: 0;
    font-size: 0.9rem;
    color: var(--color-text);
}

.user-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.user-info form {
    margin: 0;
}

/* Main content */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem;
}

/* Footer */
footer {
    background-color: var(--color-header);
    padding: 1rem;
    border-top: 1px solid var(--color-border);
    text-align: center;
    margin-top: 2rem;
}

footer a {
    color: var(--color-link);
    text-decoration: none;
}

footer a:hover {
    text-decoration: underline;
}

/* Forms */
form {
    margin-bottom: 1rem;
}

input, select, textarea {
    padding: 0.5rem;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    font-size: 1rem;
    width: 100%;
    max-width: 400px;
}

button {
    background-color: var(--color-primary);
    color: white;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
}

button:hover {
    background-color: #003d7a;
}

/* Flash messages */
.flash {
    padding: 1rem;
    margin-bottom: 1rem;
    border-radius: 4px;
    background-color: var(--color-success);
    color: white;
}

.flash.error {
    background-color: var(--color-error);
    color: white;
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 1rem;
}

th, td {
    padding: 0.5rem;
    text-align: left;
    border-bottom: 1px solid var(--color-border);
}

th {
    background-color: var(--color-header);
    font-weight: bold;
}

/* Responsive */
@media (max-width: 768px) {
    header {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .user-info {
        justify-content: center;
    }
    
    main {
        padding: 0.5rem;
    }
}

/* Focus styles for accessibility */
a:focus,
button:focus,
input:focus,
select:focus,
textarea:focus {
    outline: 2px solid #80d4ff;
    outline-offset: 2px;
}

/* Responsive table container */
.table-container {
    overflow-x: auto;
    margin-bottom: 1rem;
}

/* Error page */
.error-page {
    text-align: center;
    padding: 2rem;
}

.error-page h1 {
    color: var(--color-error);
}

/* File upload */
.file-upload {
    margin-top: 1rem;
}

.file-upload input[type="file"] {
    margin-bottom: 0.5rem;
}

/* Admin navigation */
.admin-nav {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.admin-nav a {
    text-decoration: none;
    color: var(--color-link);
    padding: 0.5rem 1rem;
    border: 1px solid var(--color-border);
    border-radius: 4px;
}

.admin-nav a:hover {
    background-color: var(--color-header);
}