/**
 * Geography Quiz App – Haupt-Stylesheet und Design-System
 *
 * CSS Custom Properties (Design Tokens), wiederverwendbare Komponenten,
 * Mobile-First Media Queries, Barrierefreiheit (WCAG 2.1 AA).
 *
 * Farbkontraste: Text 4.5:1, UI-Elemente 3:1
 * Fokus-Indikator: 3:1 Kontrast
 * prefers-reduced-motion: Animationen deaktiviert
 */

/* ==========================================================================
   1. CSS Custom Properties (Design Tokens)
   ========================================================================== */

:root {
    /* Farben – Primär (Grün/Natur für Geographie-Thema) */
    --color-primary-50: #e8f5ec;
    --color-primary-100: #c8e6d0;
    --color-primary-200: #a5d6b3;
    --color-primary-300: #81c795;
    --color-primary-400: #66bb7f;
    --color-primary-500: #4caf69;
    --color-primary-600: #43a05f;
    --color-primary-700: #388e53;
    --color-primary-800: #2e7d47;
    --color-primary-900: #1a6b3c;

    /* Farben – Sekundär (Blau für Wasser/Ozeane) */
    --color-secondary-50: #e3f2fd;
    --color-secondary-100: #bbdefb;
    --color-secondary-200: #90caf9;
    --color-secondary-300: #64b5f6;
    --color-secondary-400: #42a5f5;
    --color-secondary-500: #2196f3;
    --color-secondary-600: #1e88e5;
    --color-secondary-700: #1976d2;
    --color-secondary-800: #1565c0;
    --color-secondary-900: #0d47a1;

    /* Farben – Akzent (Warm/Gold für Erfolge) */
    --color-accent-50: #fff8e1;
    --color-accent-100: #ffecb3;
    --color-accent-200: #ffe082;
    --color-accent-300: #ffd54f;
    --color-accent-400: #ffca28;
    --color-accent-500: #ffc107;
    --color-accent-600: #ffb300;
    --color-accent-700: #ffa000;
    --color-accent-800: #ff8f00;
    --color-accent-900: #ff6f00;

    /* Farben – Neutral */
    --color-neutral-0: #ffffff;
    --color-neutral-50: #fafafa;
    --color-neutral-100: #f5f5f5;
    --color-neutral-200: #eeeeee;
    --color-neutral-300: #e0e0e0;
    --color-neutral-400: #bdbdbd;
    --color-neutral-500: #9e9e9e;
    --color-neutral-600: #757575;
    --color-neutral-700: #616161;
    --color-neutral-800: #424242;
    --color-neutral-900: #212121;

    /* Farben – Semantisch */
    --color-success: #2e7d32;
    --color-success-bg: #e8f5e9;
    --color-error: #c62828;
    --color-error-bg: #ffebee;
    --color-warning: #f57f17;
    --color-warning-bg: #fff8e1;
    --color-info: #1565c0;
    --color-info-bg: #e3f2fd;

    /* Typografie */
    --font-family-base: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-family-heading: var(--font-family-base);
    --font-family-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', monospace;

    --font-size-xs: 0.75rem;    /* 12px */
    --font-size-sm: 0.875rem;   /* 14px */
    --font-size-base: 1rem;     /* 16px */
    --font-size-md: 1.125rem;   /* 18px */
    --font-size-lg: 1.25rem;    /* 20px */
    --font-size-xl: 1.5rem;     /* 24px */
    --font-size-2xl: 1.875rem;  /* 30px */
    --font-size-3xl: 2.25rem;   /* 36px */
    --font-size-4xl: 3rem;      /* 48px */

    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    --line-height-tight: 1.25;
    --line-height-base: 1.5;
    --line-height-relaxed: 1.75;

    /* Abstände */
    --spacing-xs: 0.25rem;   /* 4px */
    --spacing-sm: 0.5rem;    /* 8px */
    --spacing-md: 1rem;      /* 16px */
    --spacing-lg: 1.5rem;    /* 24px */
    --spacing-xl: 2rem;      /* 32px */
    --spacing-2xl: 3rem;     /* 48px */
    --spacing-3xl: 4rem;     /* 64px */

    /* Radien */
    --radius-sm: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;

    /* Schatten */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);

    /* Übergänge */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
    --transition-slow: 350ms ease;

    /* Z-Index-Skala */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-modal-backdrop: 300;
    --z-modal: 400;
    --z-toast: 500;
    --z-tooltip: 600;

    /* Layout */
    --container-max: 1200px;
    --header-height: 4rem;
    --footer-height: auto;

    /* Fokus */
    --focus-ring-color: var(--color-secondary-500);
    --focus-ring-offset: 2px;
    --focus-ring-width: 3px;
}

/* ==========================================================================
   2. Reset und Basis-Stile
   ========================================================================== */

*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 100%;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--color-neutral-900);
    background-color: var(--color-neutral-50);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img,
svg {
    display: block;
    max-width: 100%;
    height: auto;
}

a {
    color: var(--color-primary-700);
    text-decoration: underline;
    text-decoration-skip-ink: auto;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--color-primary-900);
}

/* ==========================================================================
   3. Fokus-Indikatoren (WCAG 2.1 AA – 3:1 Kontrast)
   ========================================================================== */

:focus-visible {
    outline: var(--focus-ring-width) solid var(--focus-ring-color);
    outline-offset: var(--focus-ring-offset);
    border-radius: var(--radius-sm);
}

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

/* ==========================================================================
   4. Skip-Link
   ========================================================================== */

.skip-link {
    position: absolute;
    top: -100%;
    left: var(--spacing-md);
    z-index: var(--z-tooltip);
    padding: var(--spacing-sm) var(--spacing-md);
    background-color: var(--color-primary-900);
    color: var(--color-neutral-0);
    font-weight: var(--font-weight-semibold);
    text-decoration: none;
    border-radius: 0 0 var(--radius-md) var(--radius-md);
    transition: top var(--transition-fast);
}

.skip-link:focus {
    top: 0;
    outline: var(--focus-ring-width) solid var(--color-accent-400);
    outline-offset: var(--focus-ring-offset);
}

/* ==========================================================================
   5. Typografie
   ========================================================================== */

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-family-heading);
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    color: var(--color-neutral-900);
}

h1 { font-size: var(--font-size-3xl); margin-bottom: var(--spacing-lg); }
h2 { font-size: var(--font-size-2xl); margin-bottom: var(--spacing-md); }
h3 { font-size: var(--font-size-xl); margin-bottom: var(--spacing-md); }
h4 { font-size: var(--font-size-lg); margin-bottom: var(--spacing-sm); }
h5 { font-size: var(--font-size-md); margin-bottom: var(--spacing-sm); }
h6 { font-size: var(--font-size-base); margin-bottom: var(--spacing-sm); }

p {
    margin-bottom: var(--spacing-md);
}

/* ==========================================================================
   6. Layout-Komponenten
   ========================================================================== */

/* Site Header */
.site-header {
    position: sticky;
    top: 0;
    z-index: var(--z-sticky);
    background-color: var(--color-neutral-0);
    border-bottom: 1px solid var(--color-neutral-200);
    box-shadow: var(--shadow-sm);
    height: var(--header-height);
}

.site-header__container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
    height: 100%;
}

.site-header__logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    text-decoration: none;
    color: var(--color-primary-800);
    font-weight: var(--font-weight-bold);
    font-size: var(--font-size-lg);
}

.site-header__logo-icon {
    font-size: var(--font-size-xl);
}

/* Site Navigation */
.site-nav__list {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    list-style: none;
}

.site-nav__link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    color: var(--color-neutral-700);
    text-decoration: none;
    font-weight: var(--font-weight-medium);
    border-radius: var(--radius-md);
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.site-nav__link:hover {
    background-color: var(--color-primary-50);
    color: var(--color-primary-800);
}

.site-nav__link[aria-current="page"] {
    background-color: var(--color-primary-100);
    color: var(--color-primary-900);
}

.site-nav__link--login {
    background-color: var(--color-primary-600);
    color: var(--color-neutral-0);
    border-radius: var(--radius-full);
    padding: var(--spacing-sm) var(--spacing-lg);
}

.site-nav__link--login:hover {
    background-color: var(--color-primary-700);
    color: var(--color-neutral-0);
}

/* Site Main */
.site-main {
    flex: 1;
    max-width: var(--container-max);
    width: 100%;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-md);
}

.site-main:focus {
    outline: none;
}

/* Site Footer */
.site-footer {
    background-color: var(--color-neutral-800);
    color: var(--color-neutral-300);
    padding: var(--spacing-xl) var(--spacing-md);
    margin-top: auto;
}

.site-footer__container {
    max-width: var(--container-max);
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-md);
}

.site-footer__links {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    justify-content: center;
}

.site-footer__link {
    color: var(--color-neutral-300);
    text-decoration: none;
    font-size: var(--font-size-sm);
    background: none;
    border: none;
    cursor: pointer;
    font-family: inherit;
    transition: color var(--transition-fast);
}

.site-footer__link:hover {
    color: var(--color-neutral-0);
    text-decoration: underline;
}

.site-footer__copyright {
    font-size: var(--font-size-xs);
    color: var(--color-neutral-500);
    margin-bottom: 0;
}

/* ==========================================================================
   7. Buttons
   ========================================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    line-height: var(--line-height-base);
    text-decoration: none;
    border: 2px solid transparent;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: background-color var(--transition-fast),
                border-color var(--transition-fast),
                color var(--transition-fast),
                transform var(--transition-fast),
                box-shadow var(--transition-fast);
    min-height: 44px;
    min-width: 44px;
}

.btn:active {
    transform: scale(0.97);
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

/* Primary Button */
.btn--primary {
    background-color: var(--color-primary-600);
    color: var(--color-neutral-0);
    border-color: var(--color-primary-600);
}

.btn--primary:hover:not(:disabled) {
    background-color: var(--color-primary-700);
    border-color: var(--color-primary-700);
    box-shadow: var(--shadow-md);
}

/* Secondary Button */
.btn--secondary {
    background-color: var(--color-neutral-0);
    color: var(--color-primary-700);
    border-color: var(--color-primary-300);
}

.btn--secondary:hover:not(:disabled) {
    background-color: var(--color-primary-50);
    border-color: var(--color-primary-500);
}

/* Outline Button */
.btn--outline {
    background-color: transparent;
    color: var(--color-neutral-700);
    border-color: var(--color-neutral-300);
}

.btn--outline:hover:not(:disabled) {
    background-color: var(--color-neutral-100);
    border-color: var(--color-neutral-400);
}

/* Danger Button */
.btn--danger {
    background-color: var(--color-error);
    color: var(--color-neutral-0);
    border-color: var(--color-error);
}

.btn--danger:hover:not(:disabled) {
    background-color: #b71c1c;
    border-color: #b71c1c;
}

/* Button Sizes */
.btn--sm {
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: var(--font-size-sm);
    min-height: 36px;
}

.btn--lg {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: var(--font-size-lg);
    min-height: 52px;
}

/* Button Full Width */
.btn--full {
    width: 100%;
}

/* ==========================================================================
   8. Cards
   ========================================================================== */

.card {
    background-color: var(--color-neutral-0);
    border: 1px solid var(--color-neutral-200);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--transition-base), transform var(--transition-base);
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.card--interactive {
    cursor: pointer;
}

.card--interactive:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.card__header {
    margin-bottom: var(--spacing-md);
}

.card__title {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    margin-bottom: var(--spacing-xs);
}

.card__subtitle {
    font-size: var(--font-size-sm);
    color: var(--color-neutral-600);
    margin-bottom: 0;
}

.card__body {
    margin-bottom: var(--spacing-md);
}

.card__footer {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--color-neutral-200);
}

/* Card Grid */
.card-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

/* ==========================================================================
   9. Eingabefelder (Forms)
   ========================================================================== */

.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-neutral-700);
    margin-bottom: var(--spacing-xs);
}

.form-input {
    display: block;
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--color-neutral-900);
    background-color: var(--color-neutral-0);
    border: 2px solid var(--color-neutral-300);
    border-radius: var(--radius-md);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    min-height: 44px;
}

.form-input:hover {
    border-color: var(--color-neutral-400);
}

.form-input:focus {
    border-color: var(--color-primary-500);
    box-shadow: 0 0 0 3px rgba(76, 175, 105, 0.2);
    outline: none;
}

.form-input--error {
    border-color: var(--color-error);
}

.form-input--error:focus {
    box-shadow: 0 0 0 3px rgba(198, 40, 40, 0.2);
}

.form-error {
    display: block;
    font-size: var(--font-size-sm);
    color: var(--color-error);
    margin-top: var(--spacing-xs);
}

.form-hint {
    display: block;
    font-size: var(--font-size-xs);
    color: var(--color-neutral-600);
    margin-top: var(--spacing-xs);
}

/* Select */
.form-select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%23616161' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right var(--spacing-md) center;
    padding-right: var(--spacing-2xl);
}

/* ==========================================================================
   10. Modale
   ========================================================================== */

.modal-backdrop {
    position: fixed;
    inset: 0;
    z-index: var(--z-modal-backdrop);
    background-color: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-base), visibility var(--transition-base);
}

.modal-backdrop--visible {
    opacity: 1;
    visibility: visible;
}

.modal {
    background-color: var(--color-neutral-0);
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    transform: scale(0.95) translateY(10px);
    transition: transform var(--transition-base);
}

.modal-backdrop--visible .modal {
    transform: scale(1) translateY(0);
}

.modal__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--color-neutral-200);
}

.modal__title {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    margin-bottom: 0;
}

.modal__close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: none;
    border: none;
    border-radius: var(--radius-full);
    cursor: pointer;
    color: var(--color-neutral-600);
    font-size: var(--font-size-xl);
    transition: background-color var(--transition-fast);
}

.modal__close:hover {
    background-color: var(--color-neutral-100);
}

.modal__body {
    padding: var(--spacing-lg);
}

.modal__footer {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: var(--spacing-sm);
    padding: var(--spacing-lg);
    border-top: 1px solid var(--color-neutral-200);
}

/* ==========================================================================
   11. Loading-Indikatoren
   ========================================================================== */

.loading-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-3xl);
    gap: var(--spacing-md);
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 4px solid var(--color-neutral-200);
    border-top-color: var(--color-primary-500);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* ==========================================================================
   12. Badges und Tags
   ========================================================================== */

.badge {
    display: inline-flex;
    align-items: center;
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    border-radius: var(--radius-full);
    line-height: 1;
}

.badge--success {
    background-color: var(--color-success-bg);
    color: var(--color-success);
}

.badge--error {
    background-color: var(--color-error-bg);
    color: var(--color-error);
}

.badge--warning {
    background-color: var(--color-warning-bg);
    color: var(--color-warning);
}

.badge--info {
    background-color: var(--color-info-bg);
    color: var(--color-info);
}

/* ==========================================================================
   13. Utility-Klassen
   ========================================================================== */

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ==========================================================================
   14. Error Page
   ========================================================================== */

.error-page {
    text-align: center;
    padding: var(--spacing-3xl) var(--spacing-md);
}

.error-page h1 {
    font-size: var(--font-size-3xl);
    color: var(--color-neutral-800);
    margin-bottom: var(--spacing-md);
}

.error-page p {
    font-size: var(--font-size-lg);
    color: var(--color-neutral-600);
    margin-bottom: var(--spacing-xl);
}

/* ==========================================================================
   15. prefers-reduced-motion
   ========================================================================== */

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

    .loading-spinner {
        animation: none;
        border-top-color: var(--color-primary-500);
        opacity: 0.7;
    }

    .card--interactive:hover {
        transform: none;
    }

    .btn:active {
        transform: none;
    }
}

/* ==========================================================================
   16. Media Queries (Mobile-First)
   ========================================================================== */

/* Small devices (phones, 320px and up) – base styles above */

/* Medium devices (tablets, 768px and up) */
@media (min-width: 768px) {
    :root {
        --font-size-3xl: 2.5rem;
        --font-size-4xl: 3.5rem;
    }

    .site-main {
        padding: var(--spacing-2xl) var(--spacing-lg);
    }

    .card-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .site-footer__container {
        flex-direction: row;
        justify-content: space-between;
    }
}

/* Large devices (desktops, 1024px and up) */
@media (min-width: 1024px) {
    .card-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .site-main {
        padding: var(--spacing-2xl) var(--spacing-xl);
    }
}

/* Extra large devices (large desktops, 1920px and up) */
@media (min-width: 1920px) {
    :root {
        --container-max: 1400px;
    }
}

/* High contrast mode support */
@media (forced-colors: active) {
    .btn {
        border: 2px solid ButtonText;
    }

    .form-input {
        border: 2px solid ButtonText;
    }

    .card {
        border: 2px solid CanvasText;
    }
}

/* ==========================================================================
   17. Animationen und Übergänge (Task 15.1)
   ========================================================================== */

/* Seitenwechsel-Animation */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-16px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(16px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes scaleIn {
    from { opacity: 0; transform: scale(0.95); }
    to { opacity: 1; transform: scale(1); }
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

/* Seiten-Inhalt Animation */
.site-main[aria-busy="false"] > * {
    animation: fadeIn var(--transition-base) ease-out;
}

/* Hover-Effekte für interaktive Elemente */
.btn:hover:not(:disabled) {
    transform: translateY(-1px);
}

.card--interactive:hover {
    transform: translateY(-3px);
}

/* Spielinteraktions-Feedback */
.quiz-feedback--correct {
    animation: pulse 0.4s ease;
    background-color: var(--color-success-bg) !important;
    border-color: var(--color-success) !important;
}

.quiz-feedback--wrong {
    animation: shake 0.4s ease;
    background-color: var(--color-error-bg) !important;
    border-color: var(--color-error) !important;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    20% { transform: translateX(-4px); }
    40% { transform: translateX(4px); }
    60% { transform: translateX(-4px); }
    80% { transform: translateX(4px); }
}

/* Ladeanimation */
.loading-overlay {
    position: fixed;
    inset: 0;
    z-index: var(--z-modal-backdrop);
    background: rgba(255, 255, 255, 0.85);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-fast), visibility var(--transition-fast);
}

.loading-overlay--active {
    opacity: 1;
    visibility: visible;
}

.loading-dots {
    display: flex;
    gap: 6px;
}

.loading-dots span {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--color-primary-500);
    animation: loadingBounce 1.2s infinite ease-in-out;
}

.loading-dots span:nth-child(2) { animation-delay: 0.2s; }
.loading-dots span:nth-child(3) { animation-delay: 0.4s; }

@keyframes loadingBounce {
    0%, 80%, 100% { transform: scale(0.6); opacity: 0.5; }
    40% { transform: scale(1); opacity: 1; }
}

/* ==========================================================================
   18. Responsive Design Finalisierung (Task 15.2)
   ========================================================================== */

/* Touch-Ziele mindestens 44x44px */
button,
a,
input,
select,
[role="button"],
[tabindex="0"] {
    min-height: 44px;
    min-width: 44px;
}

/* Inline-Links brauchen keine min-height */
p a,
li a,
span a {
    min-height: auto;
    min-width: auto;
}

/* 200% Zoom ohne horizontales Scrollen */
@media (max-width: 320px) {
    :root {
        --font-size-3xl: 1.5rem;
        --font-size-2xl: 1.25rem;
        --font-size-xl: 1.125rem;
    }

    .site-main {
        padding: var(--spacing-md) var(--spacing-sm);
    }

    .card {
        padding: var(--spacing-md);
    }

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

/* Ensure no horizontal overflow */
html {
    overflow-x: hidden;
}

body {
    overflow-x: hidden;
    max-width: 100vw;
}

/* ==========================================================================
   19. Performance-Optimierungen (Task 15.3)
   ========================================================================== */

/* Explizite Dimensionen für Medien (CLS-Vermeidung) */
img {
    aspect-ratio: attr(width) / attr(height);
}

/* GPU-beschleunigte Animationen */
.card--interactive,
.btn,
.modal {
    will-change: transform;
}

/* Content-Visibility für Off-Screen-Elemente */
.site-footer {
    content-visibility: auto;
    contain-intrinsic-size: 0 200px;
}

/* Kritisches CSS: Sicherstellen dass above-the-fold schnell rendert */
.site-header,
.site-main {
    contain: layout style;
}

/* ==========================================================================
   17. Quiz-Select Seite
   ========================================================================== */

.quiz-select__step--hidden {
    display: none;
}

.quiz-select__intro {
    color: var(--color-neutral-600);
    margin-bottom: var(--spacing-xl);
}

.card--selected {
    border-color: var(--color-primary-500) !important;
    background-color: var(--color-primary-50) !important;
    box-shadow: 0 0 0 3px rgba(76, 175, 105, 0.3), var(--shadow-md) !important;
    transform: translateY(-2px);
}

.card--selected .card__title {
    color: var(--color-primary-800);
}

.card__icon {
    display: block;
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.quiz-select__actions {
    margin-top: var(--spacing-xl);
}

/* ==========================================================================
   18. Quiz-Play Seite
   ========================================================================== */

.quiz-play {
    max-width: 700px;
    margin: 0 auto;
}

.quiz-play__header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.quiz-play__progress {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.quiz-play__progress-bar {
    width: 100px;
    height: 6px;
    background: var(--color-neutral-200);
    border-radius: 3px;
    overflow: hidden;
}

.quiz-play__progress-fill {
    height: 100%;
    background: var(--color-primary-500);
    border-radius: 3px;
    transition: width 0.3s ease;
}

.quiz-play__prompt {
    font-size: var(--font-size-xl);
    text-align: center;
    margin-bottom: var(--spacing-xl);
    color: var(--color-neutral-800);
}

.quiz-play__options {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
}

@media (max-width: 600px) {
    .quiz-play__options {
        grid-template-columns: 1fr;
    }
}

.quiz-play__option {
    padding: var(--spacing-lg);
    border: 2px solid var(--color-neutral-200);
    border-radius: var(--radius-lg);
    background: var(--color-neutral-0);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-medium);
    cursor: pointer;
    transition: border-color 0.2s, background-color 0.2s, transform 0.1s;
    min-height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.quiz-play__option:hover:not(:disabled) {
    border-color: var(--color-primary-300);
    background: var(--color-primary-50);
    transform: translateY(-1px);
}

.quiz-play__option:disabled {
    cursor: default;
    opacity: 0.8;
}

.quiz-play__option--correct {
    border-color: var(--color-success) !important;
    background: var(--color-success-bg) !important;
    color: var(--color-success);
    font-weight: var(--font-weight-bold);
}

.quiz-play__option--wrong {
    border-color: var(--color-error) !important;
    background: var(--color-error-bg) !important;
    color: var(--color-error);
}

.quiz-play__timer {
    font-weight: var(--font-weight-semibold);
}

/* Quiz Result */
.quiz-result {
    text-align: center;
    padding: var(--spacing-2xl) var(--spacing-md);
}

.quiz-result__summary {
    display: flex;
    justify-content: center;
    gap: var(--spacing-2xl);
    margin: var(--spacing-xl) 0;
}

.quiz-result__stat {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.quiz-result__stat-value {
    font-size: var(--font-size-3xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-primary-600);
}

.quiz-result__stat-label {
    font-size: var(--font-size-sm);
    color: var(--color-neutral-600);
}

.quiz-result__actions {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    flex-wrap: wrap;
    margin-top: var(--spacing-xl);
}

/* ==========================================================================
   19. Quiz-Play Flaggen & Karten Modi
   ========================================================================== */

.quiz-play__flags {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.quiz-play__flag-items {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    justify-content: center;
}

.quiz-play__flag-item {
    width: 80px;
    height: 55px;
    border: 2px solid var(--color-neutral-300);
    border-radius: var(--radius-md);
    cursor: pointer;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-neutral-0);
    transition: border-color 0.2s, transform 0.2s;
    font-weight: bold;
    font-size: var(--font-size-sm);
}

.quiz-play__flag-item:hover {
    border-color: var(--color-primary-400);
    transform: scale(1.05);
}

.quiz-play__flag-item--selected {
    border-color: var(--color-primary-500) !important;
    box-shadow: 0 0 0 3px rgba(76, 175, 105, 0.3);
    transform: scale(1.1);
}

.quiz-play__flag-item--assigned {
    opacity: 0.4;
    pointer-events: none;
}

.quiz-play__flag-item img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.quiz-play__flag-targets {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: var(--spacing-md);
}

.quiz-play__flag-target {
    padding: var(--spacing-md);
    border: 2px dashed var(--color-neutral-300);
    border-radius: var(--radius-md);
    cursor: pointer;
    text-align: center;
    font-weight: var(--font-weight-medium);
    transition: border-color 0.2s, background-color 0.2s;
    min-height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.quiz-play__flag-target:hover {
    border-color: var(--color-primary-400);
    background: var(--color-primary-50);
}

.quiz-play__flag-target--assigned {
    border-color: var(--color-success);
    border-style: solid;
    background: var(--color-success-bg);
    pointer-events: none;
}

.quiz-play__hint {
    text-align: center;
    font-size: var(--font-size-sm);
    color: var(--color-neutral-500);
    margin-top: var(--spacing-md);
}

.quiz-play__map-container {
    width: 100%;
    aspect-ratio: 4/3;
    border: 2px solid var(--color-neutral-200);
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--color-neutral-50);
}

.quiz-play__map-container svg {
    width: 100%;
    height: 100%;
}