@layer reset, base, components, utilities, overrides;

/* ============================================
   Reset
   ============================================ */
@layer reset {
    *,
    *::before,
    *::after {
        box-sizing: border-box;
    }

    * {
        margin: 0;
    }

    html {
        -webkit-text-size-adjust: 100%;
    }

    body {
        line-height: 1.6;
        -webkit-font-smoothing: antialiased;
    }

    img,
    picture,
    video,
    canvas,
    svg {
        display: block;
        max-width: 100%;
    }

    input,
    button,
    textarea,
    select {
        font: inherit;
    }

    p,
    h1,
    h2,
    h3,
    h4,
    h5,
    h6 {
        overflow-wrap: break-word;
    }
}

/* ============================================
   Base - element defaults
   ============================================ */
@layer base {
    body {
        font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
        background-color: var(--background);
        color: var(--text-primary);
        font-size: var(--font-size-base);
    }

    /* Focus styles */
    :focus-visible {
        outline: 2px solid var(--primary-color);
        outline-offset: 2px;
    }

    :focus:not(:focus-visible) {
        outline: none;
    }

    /* Reduced motion */
    @media (prefers-reduced-motion: reduce) {
        *,
        *::before,
        *::after {
            animation-duration: 0.01ms !important;
            animation-iteration-count: 1 !important;
            transition-duration: 0.01ms !important;
        }
    }
}

/* ============================================
   Shared components
   ============================================ */
@layer components {

    /* Header */
    .header {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        height: var(--header-height);
        background: var(--surface);
        border-bottom: 1px solid var(--border-color);
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: 0 var(--spacing-lg);
        z-index: 100;
    }

    .header-logo h1 {
        font-size: var(--font-size-xl);
        font-weight: 600;
        color: var(--primary-color);
    }

    .version-info {
        font-size: var(--font-size-xs);
        color: var(--text-secondary);
    }

    .header-user {
        display: flex;
        align-items: center;
        gap: var(--spacing-base);
    }

    .header-user span {
        color: var(--text-secondary);
    }

    /* Theme toggle */
    .theme-toggle-btn {
        background: none;
        border: none;
        cursor: pointer;
        font-size: var(--font-size-lg);
        padding: var(--spacing-xs);
        line-height: 1;
        color: var(--text-secondary);
        transition: color var(--transition-base);
        border-radius: var(--radius-sm);
    }

    .theme-toggle-btn:hover {
        color: var(--text-primary);
        background: var(--surface-elevated);
    }

    /* Header left section */
    .header-left {
        display: flex;
        align-items: center;
        gap: var(--spacing-md);
    }

    /* Main layout */
    .main {
        padding-top: var(--header-height);
        min-height: 100vh;
    }

    /* Sidebar toggle button (hamburger) */
    .sidebar-toggle-btn {
        display: none;
        background: none;
        border: none;
        cursor: pointer;
        padding: var(--spacing-sm);
        border-radius: var(--radius-sm);
        transition: background-color var(--transition-base);
    }

    .sidebar-toggle-btn:hover {
        background: var(--surface-elevated);
    }

    .hamburger {
        display: block;
        width: 20px;
        height: 2px;
        background: var(--text-primary);
        position: relative;
    }

    .hamburger::before,
    .hamburger::after {
        content: '';
        position: absolute;
        width: 20px;
        height: 2px;
        background: var(--text-primary);
        left: 0;
    }

    .hamburger::before {
        top: -6px;
    }

    .hamburger::after {
        top: 6px;
    }

    /* Buttons */
    .btn {
        display: inline-block;
        padding: var(--spacing-md) var(--spacing-lg);
        border: none;
        border-radius: var(--radius-sm);
        font-size: var(--font-size-base);
        cursor: pointer;
        text-decoration: none;
        transition: background-color var(--transition-base);
    }

    .btn-primary {
        background: var(--primary-color);
        color: white;
    }

    .btn-primary:hover {
        background: var(--primary-dark);
    }

    .btn-secondary {
        background: var(--background);
        color: var(--text-primary);
        border: 1px solid var(--border-color);
    }

    .btn-secondary:hover {
        background: var(--border-color);
    }

    .btn-sm {
        padding: var(--spacing-xs) var(--spacing-md);
        font-size: var(--font-size-sm);
    }

    .btn:disabled {
        opacity: 0.4;
        cursor: not-allowed;
    }

    /* Flash messages */
    .flash-messages {
        padding: 0 var(--spacing-lg);
        margin-top: var(--spacing-md);
    }

    .flash {
        padding: var(--spacing-md) var(--spacing-base);
        border-radius: var(--radius-sm);
        margin-bottom: var(--spacing-md);
        font-size: var(--font-size-base);
    }

    .flash-error {
        background: rgba(239, 83, 80, 0.15);
        color: var(--error-color);
        border: 1px solid var(--error-color);
    }

    .flash-info {
        background: rgba(66, 165, 245, 0.15);
        color: var(--primary-color);
        border: 1px solid var(--primary-color);
    }

    .flash-success {
        background: rgba(102, 187, 106, 0.15);
        color: var(--success-color);
        border: 1px solid var(--success-color);
    }

    [data-theme="light"] .flash-error {
        background: #ffebee;
    }

    [data-theme="light"] .flash-info {
        background: #e3f2fd;
    }

    [data-theme="light"] .flash-success {
        background: #e8f5e9;
    }

    /* Loading states */
    .loading {
        text-align: center;
        color: var(--text-secondary);
        padding: var(--spacing-3xl);
        font-size: var(--font-size-base);
    }

    .content-loader {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: var(--spacing-lg);
        padding: 80px var(--spacing-lg);
        color: var(--text-secondary);
        font-size: var(--font-size-base);
    }

    .loader-spinner {
        width: 40px;
        height: 40px;
        border: 3px solid var(--border-color);
        border-top-color: var(--primary-color);
        border-radius: var(--radius-full);
        animation: spin 0.8s linear infinite;
    }

    @keyframes spin {
        to { transform: rotate(360deg); }
    }

    /* Error and empty states */
    .error-message,
    .no-data {
        text-align: center;
        padding: var(--spacing-lg);
        color: var(--text-secondary);
        font-size: var(--font-size-base);
    }

    .error-message {
        color: var(--error-color);
        background: rgba(239, 83, 80, 0.15);
        border-radius: var(--radius-sm);
    }

    [data-theme="light"] .error-message {
        background: #ffebee;
    }

    /* Force light color scheme for form elements in light mode */
    [data-theme="light"] input[type="checkbox"],
    [data-theme="light"] input[type="text"],
    [data-theme="light"] input[type="password"],
    [data-theme="light"] input[type="search"] {
        color-scheme: light;
    }

} /* end @layer components */

/* ============================================
   Utilities
   ============================================ */
@layer utilities {
    .sr-only {
        position: absolute;
        width: 1px;
        height: 1px;
        padding: 0;
        margin: -1px;
        overflow: hidden;
        clip: rect(0, 0, 0, 0);
        white-space: nowrap;
        border: 0;
    }
}

/* ============================================
   Overrides - shared responsive and a11y
   ============================================ */
@layer overrides {

    @media (max-width: 900px) {
        .sidebar-toggle-btn {
            display: block;
        }

        .header {
            padding: 0 var(--spacing-base);
        }

        .header-logo h1 {
            font-size: var(--font-size-base);
        }

        .header-user span {
            display: none;
        }

        .header-user {
            gap: var(--spacing-md);
        }

        .btn-secondary {
            padding: var(--spacing-sm) var(--spacing-md);
            font-size: var(--font-size-sm);
        }
    }

    @media (max-width: 480px) {
        .header-logo h1 {
            font-size: var(--font-size-sm);
        }
    }

    /* High contrast preference */
    @media (prefers-contrast: more) {
        :root {
            --border-color: #000000;
        }
        [data-theme="light"] {
            --border-color: #000000;
            --text-secondary: #444444;
        }
        .btn {
            border-width: 2px;
        }
    }

    /* Windows High Contrast / forced colors */
    @media (forced-colors: active) {
        .btn {
            border: 2px solid currentColor;
        }
    }

} /* end @layer overrides */