/* Reset and Base Styles */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body, html {
    height: 100%;
    width: 100%;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    overflow: hidden;
}

body.page-body {
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    background: #f4f4f4;
    overflow: auto;
}

/* Generic Components */
.btn {
    width: 100%;
    padding: 0.75rem;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
    transition: opacity 0.2s;
}
.btn:hover { opacity: 0.9; }
.btn-primary { background: #007bff; }
.btn-success { background: #28a745; }
.btn-secondary { background: #6c757d; margin-top: 10px; }

.hidden { display: none !important; }