/* --- FONTS --- */
        @font-face { font-family: 'Noto Sans'; font-style: normal; font-weight: 400; src: url('fonts/NotoSans-Regular.ttf') format('truetype'); font-display: swap; }
        @font-face { font-family: 'Noto Sans'; font-style: normal; font-weight: 500; src: url('fonts/NotoSans-Medium.ttf') format('truetype'); font-display: swap; }
        @font-face { font-family: 'Noto Sans'; font-style: normal; font-weight: 700; src: url('fonts/NotoSans-Bold.ttf') format('truetype'); font-display: swap; }

        /* --- BASE CSS --- */
        :root {
            --font-main: 'Noto Sans', sans-serif;
            --color-bg: #ffffff;
            --color-text: #000000; 
            --color-primary: #2563eb;
            --color-primary-dark: #1e40af;
            --color-border: #e5e7eb;
            --color-subtle: #6b7280;
            --focus-ring: 3px solid #000000;
            --focus-offset: 2px;
            --container-width: 1200px;
            --radius-md: 8px;
            --color-error: #c00; 
            --color-error-bg: #fff0f0; 
            --color-success: #008000;
            --color-success-bg: #f0fff0;
        }

        *:focus-visible {
            outline: var(--focus-ring) !important;
            outline-offset: var(--focus-offset) !important;
            border-radius: 2px;
        }
        
        input[aria-invalid="true"],
        select[aria-invalid="true"] {
            border-color: var(--color-error);
            border-width: 2px;
        }

        body, h1, h2, h3, p, ul, li { margin: 0; padding: 0; }
        
        body {
            font-family: var(--font-main);
            background-color: var(--color-bg);
            color: var(--color-text);
            line-height: 1.6;
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }

        /* FIXED: Skip Link CSS (Hidden until focused) */
        .skip-link { 
            position: absolute; 
            top: -9999px; 
            left: 50%; 
            transform: translateX(-50%);
            background-color: var(--color-primary); 
            color: #ffffff; 
            padding: 1rem 1.5rem; 
            z-index: 99999; 
            text-decoration: none; 
            font-weight: 700;
            border-radius: 0 0 var(--radius-md) var(--radius-md);
        }
        .skip-link:focus { top: 0; outline: var(--focus-ring); outline-offset: -3px; }

        .container { max-width: var(--container-width); margin: 0 auto; padding: 0 1.5rem; }
        .sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); border: 0; }
        
        /* HEADER */
        .site-header { padding: 0.75rem 0; border-bottom: 1px solid var(--color-border); position: sticky; top: 0; z-index: 1000; background-color: var(--color-bg); }
        .header-inner { display: flex; justify-content: space-between; align-items: center; position: relative; flex-wrap: wrap; }
        .logo { font-weight: 700; font-size: 1.5rem; text-decoration: none; color: #272727ff; }
        .logo-highlight { color: var(--color-primary); }
        
        .main-nav ul { display: flex; gap: 1.5rem; list-style: none; }
        .main-nav a { text-decoration: none; color: var(--color-text); font-weight: 500; font-size: 1.1rem; text-decoration: underline; }
        .main-nav a:hover { text-decoration: none; }
        
        /* Mobile Toggle */
        .mobile-nav-toggle { display: none; background: transparent; border: 0; padding: 0.5rem; cursor: pointer; }
        .mobile-nav-toggle-icon { display: block; width: 28px; height: 3px; background: var(--color-text); border-radius: 2px; position: relative; }
        .mobile-nav-toggle-icon::before, .mobile-nav-toggle-icon::after { content: ''; position: absolute; left: 0; width: 100%; height: 3px; background: var(--color-text); border-radius: 2px; transition: transform 0.3s ease; }
        .mobile-nav-toggle-icon::before { transform: translateY(-8px); }
        .mobile-nav-toggle-icon::after { transform: translateY(8px); }
        .mobile-nav-toggle[aria-expanded="true"] .mobile-nav-toggle-icon { background: transparent; }
        .mobile-nav-toggle[aria-expanded="true"] .mobile-nav-toggle-icon::before { transform: rotate(45deg); }
        .mobile-nav-toggle[aria-expanded="true"] .mobile-nav-toggle-icon::after { transform: rotate(-45deg); }

        .btn { display: inline-flex; align-items: center; justify-content: center; padding: 0.75rem 1.5rem; font-weight: 500; border-radius: var(--radius-md); text-decoration: none; cursor: pointer; border: 2px solid transparent; min-height: 44px; box-sizing: border-box; }
        .btn-primary { background: var(--color-primary); color: white; }
        .btn-primary:hover { background: var(--color-primary-dark); }

        .main-layout { display: grid; grid-template-columns: 1fr 3fr; gap: 3rem; margin-top: 2.5rem; margin-bottom: 3rem; flex-grow: 1; }
        #main-content { scroll-margin-top: 6rem; }
        
        .theme-5 .sidebar { order: -1; }

        /* Footer */
        .site-footer { background: #1a1a1a; color: white; padding: 2rem 0; font-size: 1rem; }
        .footer-inner { display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 1rem; }
        .footer-nav ul { list-style: none; display: flex; flex-wrap: wrap; gap: 1.5rem; padding: 0; margin: 0; }
        .footer-nav a { color: white; text-decoration: underline; }
        .footer-nav a:hover { text-decoration: none; }
        .footer-copy { margin: 0; text-align: right; }
        
        @media (min-width: 768px) { .main-nav { position: absolute; left: 50%; transform: translateX(-50%); } }

        /* Form Styles */
        .registration-container { margin: 0 auto; padding: 2rem; }
        .q-card { border: 1px solid var(--color-border); padding: 1.5rem; border-radius: var(--radius-md); }
        
        /* FIXED: Changed h2 to h1 in CSS reference */
        .login-form h1 { font-size: 1.75rem; font-weight: 700; text-align: center; margin-bottom: 2.5rem; color: var(--color-text); }
        
        .form-group { display: flex; flex-direction: column; margin-bottom: 1.25rem; }
        .form-group label { font-weight: 500; margin-bottom: 0.5rem; color: var(--color-text); font-size: 1.1rem; }
        .form-group input { width: 100%; padding: 0.75rem; border: 1px solid var(--color-border); border-radius: var(--radius-md); min-height: 44px; box-sizing: border-box; font-family: var(--font-main); font-size: 1.1rem; }
        
        .password-wrapper { position: relative; display: flex; }
        .password-wrapper input { padding-right: 3rem; }
        .toggle-password { position: absolute; right: 1px; top: 1px; bottom: 1px; width: 2.75rem; background: transparent; border: 0; border-top-right-radius: var(--radius-md); border-bottom-right-radius: var(--radius-md); cursor: pointer; display: flex; align-items: center; justify-content: center; color: var(--color-subtle); }
        .toggle-password:hover { color: var(--color-text); }

        .form-error { color: var(--color-error); font-size: 1rem; font-weight: 500; margin-top: 0.5rem; }
        .form-error-summary, .form-success-summary { border: 2px solid; padding: 1rem; border-radius: var(--radius-md); font-weight: 500; margin-bottom: 1.5rem; }
        .form-error-summary { border-color: var(--color-error); background: var(--color-error-bg); color: var(--color-error); }
        .form-success-summary { border-color: var(--color-success); background: var(--color-success-bg); color: var(--color-success); }
        .form-error-summary h3, .form-success-summary h3 { margin: 0 0 0.5rem; font-size: 1.1rem; color: #000; }
        .form-error-summary p, .form-success-summary p { color: #000; margin: 0; font-weight: 400; }

        .form-row-extra { display: flex; justify-content: space-between; align-items: center; margin-bottom: 1.25rem; flex-wrap: wrap; gap: 1rem; }
        .form-group-checkbox { display: flex; align-items: center; gap: 0.5rem; }
        
        /* FIXED: Increased checkbox size (WCAG 2.5.8) */
        .form-group-checkbox input[type="checkbox"] { width: 1.5em; height: 1.5em; flex-shrink: 0; }
        
        .form-group-checkbox label { margin: 0; font-weight: 700; font-size: 1rem; color: var(--color-text); }
        .forgot-password-link { font-size: 1rem; color: var(--color-text); text-decoration: underline; }
        .forgot-password-link:hover { text-decoration: none; }

        /* Mobile */
        @media (max-width: 768px) {
            .site-header { padding: 0.5rem 0; }
            .container { padding: 0 1rem; width: 90%; }
            .header-inner { flex-direction: row; align-items: center; flex-wrap: wrap; position: static; }
            .mobile-nav-toggle { display: block; }
            .main-nav, .header-actions { display: none; width: 100%; }
            .main-nav[data-visible="true"], .header-actions[data-visible="true"] { display: block; }
            .main-nav { order: 2; margin-top: 1.5rem; position: static; transform: none; }
            .header-actions { order: 3; margin-top: 1.5rem; }
            .main-nav ul { flex-direction: column; gap: 1rem; text-align: center; }
            .header-actions .btn { width: 100%; }
            .main-layout { margin-top: 1.5rem; gap: 1.5rem; grid-template-columns: 1fr; }
            .theme-5 .sidebar { order: unset; }
            .registration-container { padding: 1.5rem 1rem; }
            .footer-inner { flex-direction: column; align-items: center; gap: 1.5rem; }
            .footer-nav ul { justify-content: center; gap: 1rem 1.5rem; }
            .footer-copy { text-align: center; }
        }