/* ============================================
   CHINESE MASTER - Main Styles
   ============================================ */

/* CSS Variables */
:root {
    --font-cn: 'Noto Sans SC', sans-serif;
    --font-en: 'Inter', sans-serif;
    --font-size-xs: 0.75rem;
    --font-size-sm: 0.875rem;
    --font-size-base: 1rem;
    --font-size-lg: 1.125rem;
    --font-size-xl: 1.25rem;
    --font-size-2xl: 1.5rem;
    --font-size-3xl: 1.875rem;
    --font-size-4xl: 2.25rem;
    --font-size-5xl: 3rem;
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
}

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

html,
body {
    max-width: 100%;
    overflow-x: hidden;
    width: 100%;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-en);
    font-size: var(--font-size-base);
    line-height: 1.6;
    min-height: 100vh;
    min-height: 100dvh;
}

/* Chinese Text */
.cn-text,
.chinese-char,
.flashcard-character {
    font-family: var(--font-cn);
}

/* App Layout */
#app {
    display: flex;
    min-height: 100vh;
    min-height: 100dvh;
}

/* Modules */
.module {
    display: none;
    animation: fadeIn var(--transition-normal);
}

/* Navigation */
.main-nav {
    width: 260px;
    min-height: 100vh;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
    position: fixed;
    left: 0;
    top: 0;
    z-index: 100;
    transition: transform var(--transition-normal);
}

.main-nav.hidden {
    transform: translateX(-100%);
}

.nav-header {
    padding: var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

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

.logo-char {
    font-family: var(--font-cn);
    font-size: var(--font-size-2xl);
    font-weight: 700;
}

.logo-text {
    font-family: var(--font-cn);
    font-size: var(--font-size-lg);
    font-weight: 600;
}

.theme-toggle {
    background: none;
    border: none;
    font-size: var(--font-size-xl);
    cursor: pointer;
    padding: var(--spacing-xs);
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast);
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.1);
}

.nav-links {
    flex: 1;
    padding: var(--spacing-md) 0;
    display: flex;
    flex-direction: column;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    text-decoration: none;
    transition: all var(--transition-fast);
    position: relative;
}

.nav-link::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 0;
    transition: height var(--transition-fast);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.nav-link.active::before {
    height: 60%;
}

.nav-link:hover {
    background: rgba(255, 255, 255, 0.05);
}

.nav-icon {
    font-size: var(--font-size-xl);
    width: 24px;
    text-align: center;
}

.nav-text {
    font-size: var(--font-size-base);
    font-weight: 500;
}

.nav-footer {
    padding: var(--spacing-lg);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

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

.level-badge {
    font-size: var(--font-size-sm);
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.xp-bar {
    height: 6px;
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: var(--spacing-xs);
}

.xp-fill {
    height: 100%;
    width: 0%;
    border-radius: var(--radius-full);
    transition: width var(--transition-normal);
}

.xp-text {
    font-size: var(--font-size-xs);
}

.streak-display {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: var(--font-size-sm);
}

.streak-icon {
    font-size: var(--font-size-lg);
}

.streak-count {
    font-weight: 700;
    font-size: var(--font-size-lg);
}

.streak-label {
    opacity: 0.8;
}

/* Main Content */
.main-content {
    flex: 1;
    margin-left: 240px;
    width: calc(100% - 240px);
    max-width: calc(100% - 240px);
    padding: var(--spacing-xl);
    min-height: 100vh;
    min-height: 100dvh;
    box-sizing: border-box;
    transition: margin-left var(--transition-normal);
    position: relative;
    z-index: 1;
}

.main-content.expanded {
    margin-left: 0;
}

/* .module already declared above — only .active variant here */
.module.active {
    display: block;
}

.module-header {
    margin-bottom: var(--spacing-2xl);
}

.module-header h1 {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.module-subtitle {
    font-size: var(--font-size-lg);
    opacity: 0.8;
}

/* Dashboard */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-2xl);
}

.stats-card {
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-align: center;
    transition: transform var(--transition-fast);
}

.stats-card:hover {
    transform: translateY(-2px);
}

.stats-icon {
    font-size: var(--font-size-3xl);
    margin-bottom: var(--spacing-md);
}

.stats-value {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.stats-label {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

/* Daily Goal */
.daily-goal-section {
    margin-bottom: var(--spacing-2xl);
}

.daily-goal-section h2 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-lg);
}

.goal-progress {
    display: flex;
    align-items: center;
    gap: var(--spacing-2xl);
}

.goal-ring {
    position: relative;
    width: 150px;
    height: 150px;
}

.goal-ring svg {
    width: 100%;
    height: 100%;
    transform: rotate(-90deg);
}

.goal-bg {
    fill: none;
    stroke-width: 8;
    opacity: 0.2;
}

.goal-fill {
    fill: none;
    stroke-width: 8;
    stroke-linecap: round;
    stroke-dasharray: 251.2;
    stroke-dashoffset: 251.2;
    transition: stroke-dashoffset var(--transition-slow);
}

.goal-text {
    position: absolute;
    inset: 0;
    display: flex;
    align-items: baseline;
    justify-content: center;
    line-height: 1;
}

.goal-text span {
    font-size: var(--font-size-3xl);
    font-weight: 700;
    line-height: 1;
}

.goal-percent-sign {
    font-size: var(--font-size-sm);
    color: var(--text-muted);
    font-weight: 400;
}

.goal-details {
    flex: 1;
}

.goal-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
}

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

/* Quick Actions */
.quick-actions {
    margin-bottom: var(--spacing-2xl);
}

.quick-actions h2 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-lg);
}

.action-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: var(--spacing-lg);
}

.action-card {
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.action-card:hover {
    transform: translateY(-4px);
}

.action-icon {
    font-size: var(--font-size-3xl);
    margin-bottom: var(--spacing-md);
}

.action-card h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-xs);
}

.action-card p {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

/* Recent Activity */
.recent-activity h2 {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-lg);
}

.activity-list {
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.activity-empty {
    padding: var(--spacing-2xl);
    text-align: center;
    opacity: 0.6;
}

.activity-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

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

.activity-text {
    flex: 1;
}

.activity-time {
    font-size: var(--font-size-sm);
    opacity: 0.6;
}

/* Listening & Reading Menus */
.listening-menu,
.reading-menu,
.vocab-menu,
.grammar-menu,
.speaking-menu {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    justify-content: center;
}

.exercise-type-card,
.vocab-mode-card,
.game-card {
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-align: center;
}

.exercise-type-card:hover,
.vocab-mode-card:hover,
.game-card:hover {
    transform: translateY(-4px);
}

.type-icon,
.mode-icon {
    font-size: var(--font-size-4xl);
    margin-bottom: var(--spacing-md);
}

.exercise-type-card h3,
.vocab-mode-card h3,
.game-card h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-xs);
}

.exercise-type-card p,
.vocab-mode-card p,
.game-card p {
    font-size: var(--font-size-sm);
    opacity: 0.8;
    margin-bottom: var(--spacing-sm);
}

.type-difficulty {
    font-size: var(--font-size-xs);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-full);
    display: inline-block;
}

/* Exercise Container */
.exercise-container {
    animation: fadeIn var(--transition-normal);
}

.exercise-container.hidden {
    display: none;
}

.exercise-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
    justify-content: center;
}

.back-btn {
    background: none;
    border: none;
    font-size: var(--font-size-base);
    cursor: pointer;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast);
}

.back-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}

.exercise-title {
    flex: 1;
    font-size: var(--font-size-xl);
    font-weight: 600;
}

.exercise-progress {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

.exercise-body {
    margin-bottom: var(--spacing-xl);
}

.exercise-controls {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
}

/* Buttons */
.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.btn:hover {
    transform: translateY(-1px);
}

.btn:active {
    transform: translateY(0);
}

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

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

.btn-secondary {
    background: rgba(255, 255, 255, 0.1);
    color: inherit;
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.2);
}

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

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

.btn.hidden {
    display: none;
}

/* Flashcards */
.flashcard-area {
    max-width: 500px;
    margin: 0 auto;
    text-align: center;
}

.flashcard {
    width: 100%;
    height: 300px;
    perspective: 1000px;
    cursor: pointer;
    margin-bottom: var(--spacing-xl);
    position: relative;
}

.flashcard-front,
.flashcard-back {
    position: absolute;
    width: 100%;
    height: 100%;
    backface-visibility: hidden;
    border-radius: var(--radius-xl);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
    transition: transform 0.6s;
}

.flashcard-back {
    transform: rotateY(180deg);
}

.flashcard.flipped .flashcard-front {
    transform: rotateY(180deg);
}

.flashcard.flipped .flashcard-back {
    transform: rotateY(0);
}

.flashcard-character {
    font-size: var(--font-size-5xl);
    margin-bottom: var(--spacing-md);
}

.flashcard-pinyin {
    font-size: var(--font-size-xl);
    opacity: 0.8;
}

.flashcard-meaning {
    font-size: var(--font-size-2xl);
    margin-bottom: var(--spacing-lg);
}

.flashcard-example {
    text-align: center;
}

.example-cn {
    font-family: var(--font-cn);
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-sm);
}

.example-en {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

.flashcard-counter {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

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

.srs-btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    min-width: 80px;
}

.srs-btn:hover {
    transform: translateY(-2px);
}

.srs-btn[data-quality="1"] {
    background: var(--color-danger);
    color: white;
}

.srs-btn[data-quality="3"] {
    background: var(--color-warning);
    color: white;
}

.srs-btn[data-quality="4"] {
    background: var(--color-primary);
    color: white;
}

.srs-btn[data-quality="5"] {
    background: var(--color-success);
    color: white;
}

/* Games */
.games-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.game-area {
    margin-top: var(--spacing-xl);
}

.game-area.hidden {
    display: none;
}



.matching-card {
    aspect-ratio: 1;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
    font-size: var(--font-size-lg);
    font-weight: 600;
}

.matching-card:hover {
    transform: scale(1.05);
}

.matching-card.flipped {
    background: var(--color-primary);
    color: white;
}

.matching-card.matched {
    background: var(--color-success);
    color: white;
    cursor: default;
}

/* Listening Content */
.listening-audio-controls {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.audio-btn {
    font-size: var(--font-size-4xl);
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-lg);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

.audio-btn:hover {
    transform: scale(1.1);
}

.audio-btn.playing {
    animation: pulse 1s infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.listening-input {
    width: 100%;
    padding: var(--spacing-md);
    font-size: var(--font-size-lg);
    font-family: var(--font-cn);
    border-radius: var(--radius-md);
    margin-top: var(--spacing-md);
}

.listening-options {
    display: grid;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.listening-option {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.listening-option:hover {
    transform: translateX(4px);
}

.listening-option.selected {
    border-color: var(--color-primary);
}

.listening-option.correct {
    background: var(--color-success);
    border-color: var(--color-success);
}

.listening-option.incorrect {
    background: var(--color-danger);
    border-color: var(--color-danger);
}

.option-letter {
    width: 30px;
    height: 30px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: var(--font-size-sm);
}

/* Reading Content */
.reading-passage {
    font-family: var(--font-cn);
    font-size: var(--font-size-xl);
    line-height: 2;
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-xl);
}

.reading-passage .word {
    cursor: pointer;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast);
}

.reading-passage .word:hover {
    background: rgba(255, 255, 255, 0.1);
}

.reading-question {
    margin-bottom: var(--spacing-lg);
}

.reading-question h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
}

/* Grammar Content */
.grammar-pattern {
    font-size: var(--font-size-2xl);
    font-family: var(--font-cn);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.grammar-explanation {
    margin-bottom: var(--spacing-xl);
}

.grammar-explanation h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-md);
}

.grammar-examples {
    list-style: none;
}

.grammar-examples li {
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
    border-radius: var(--radius-md);
    font-family: var(--font-cn);
    font-size: var(--font-size-lg);
}

.grammar-examples li .example-pinyin {
    font-size: var(--font-size-sm);
    opacity: 0.8;
    display: block;
    margin-bottom: var(--spacing-xs);
}

.grammar-examples li .example-meaning {
    font-size: var(--font-size-sm);
    opacity: 0.8;
    font-family: var(--font-en);
}

/* Speaking Content */
.speaking-prompt {
    text-align: center;
    padding: var(--spacing-2xl);
}

.speaking-text {
    font-family: var(--font-cn);
    font-size: var(--font-size-3xl);
    margin-bottom: var(--spacing-lg);
}

.speaking-pinyin {
    font-size: var(--font-size-xl);
    opacity: 0.8;
    margin-bottom: var(--spacing-xl);
}

.speaking-controls {
    display: flex;
    gap: var(--spacing-lg);
    justify-content: center;
}

/* Achievements */
.achievements-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
}

.achievement-card {
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    text-align: center;
    transition: transform var(--transition-fast);
}

.achievement-card:hover {
    transform: translateY(-2px);
}

.achievement-card.locked {
    opacity: 0.5;
}

.achievement-icon {
    font-size: var(--font-size-4xl);
    margin-bottom: var(--spacing-md);
}

.achievement-card h3 {
    font-size: var(--font-size-lg);
    margin-bottom: var(--spacing-xs);
}

.achievement-card p {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

.achievement-date {
    font-size: var(--font-size-xs);
    opacity: 0.6;
    margin-top: var(--spacing-sm);
}

/* Grammar Lessons List */
.grammar-lessons-list {
    display: grid;
    gap: var(--spacing-md);
}

.grammar-lesson-item {
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.grammar-lesson-item:hover {
    transform: translateX(4px);
}

.grammar-lesson-number {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
}

.grammar-lesson-info h3 {
    font-size: var(--font-size-base);
    margin-bottom: var(--spacing-xs);
}

.grammar-lesson-info p {
    font-size: var(--font-size-sm);
    opacity: 0.8;
}

/* Toast Notifications */
.toast-container {
    position: fixed;
    top: var(--spacing-lg);
    right: var(--spacing-lg);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.toast {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    /* Entrance animation handled by GSAP (InkAnimations.initMicroInteractions) */
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    max-width: calc(100vw - 24px);
    box-sizing: border-box;
}

.toast.success {
    background: var(--color-success);
    color: white;
}

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

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

@keyframes slideIn {
    from { transform: translateX(100%); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal.hidden {
    display: none;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
}

.modal-content {
    position: relative;
    width: 90%;
    max-width: 600px;
    max-height: 80vh;
    max-height: 80dvh;
    overflow-y: auto;
    border-radius: var(--radius-xl);
    padding: var(--spacing-2xl);
    z-index: 1;
}

.modal-close {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background: none;
    border: none;
    font-size: var(--font-size-2xl);
    cursor: pointer;
    opacity: 0.7;
    transition: opacity var(--transition-fast);
}

.modal-close:hover {
    opacity: 1;
}

/* Input Fields */
.input-field {
    width: 100%;
    padding: var(--spacing-md);
    font-size: var(--font-size-base);
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    transition: border-color var(--transition-fast);
}

.input-field:focus {
    outline: none;
    border-color: var(--color-primary);
}

.input-field.correct {
    border-color: var(--color-success);
}

.input-field.incorrect {
    border-color: var(--color-danger);
}

/* Responsive Design */
@media (max-width: 768px) {
    .main-nav {
        width: 100%;
        transform: translateX(-100%);
    }

    .main-nav.mobile-open {
        transform: translateX(0);
    }

    .main-content {
        margin-left: 0;
        padding: var(--spacing-lg);
    }

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

    .goal-progress {
        flex-direction: column;
    }

    .action-cards {
        grid-template-columns: 1fr;
    }

    .listening-menu,
    .reading-menu,
    .vocab-menu,
    .grammar-menu,
    .speaking-menu {
        grid-template-columns: 1fr;
    }



    .srs-buttons {
        flex-wrap: wrap;
    }
}

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.3);
}

/* Utility Classes */
.hidden {
    display: none !important;
}

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

.mt-md {
    margin-top: var(--spacing-md);
}

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

.mt-lg {
    margin-top: var(--spacing-lg);
}

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

/* ============================================
   MISSIONS & REWARDS SYSTEM
   ============================================ */

.missions-challenge-row {
    display: grid;
    grid-template-columns: 1fr 320px;
    gap: var(--spacing-lg);
    align-items: start;
}

.missions-widget {
    background: var(--bg-card);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
}

.missions-widget-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
}

.missions-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
}

.missions-claimable-badge {
    background: linear-gradient(135deg, #5aab8a, #3d8b6a);
    color: white;
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 700;
    animation: pulse-glow 2s infinite;
}

@keyframes pulse-glow {
    0%, 100% { box-shadow: 0 0 0 0 rgba(90, 171, 138, 0.4); }
    50% { box-shadow: 0 0 12px 4px rgba(90, 171, 138, 0.3); }
}

.missions-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.mission-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 14px;
    background: var(--bg-primary);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-lg);
    transition: all 0.2s ease;
}

.mission-item.complete {
    border-color: rgba(90, 171, 138, 0.4);
    background: rgba(90, 171, 138, 0.08);
}

.mission-item.claimed {
    opacity: 0.5;
}

.mission-item.weekly {
    border-color: rgba(167, 139, 250, 0.3);
    background: rgba(167, 139, 250, 0.06);
}

.mission-icon {
    font-size: 24px;
    flex-shrink: 0;
}

.mission-info {
    flex: 1;
    min-width: 0;
}

.mission-desc {
    font-size: 13px;
    color: var(--text-primary);
    font-weight: 500;
    margin-bottom: 6px;
}

.mission-progress-bar {
    height: 4px;
    background: var(--bg-tertiary, rgba(255,255,255,0.1));
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: 4px;
}

.mission-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #5aab8a, #3d8b6a);
    border-radius: var(--radius-full);
    transition: width 0.5s ease;
}

.mission-progress-fill.weekly {
    background: linear-gradient(90deg, #a78bfa, #7c5cbf);
}

.mission-progress-text {
    font-size: 11px;
    color: var(--text-muted);
}

.mission-reward {
    flex-shrink: 0;
    text-align: center;
}

.mission-xp {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 600;
}

.mission-claimed {
    color: #5aab8a;
    font-size: 18px;
    font-weight: 700;
}

.btn-mission-claim {
    background: linear-gradient(135deg, #5aab8a, #3d8b6a);
    color: white;
    border: none;
    padding: 6px 14px;
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.15s ease, box-shadow 0.15s ease;
}

.btn-mission-claim:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(90, 171, 138, 0.4);
}

.missions-weekly-label {
    font-size: 12px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-top: 12px;
    margin-bottom: 6px;
    font-weight: 600;
}

/* Daily Challenge Card */
.daily-challenge-card {
    background: var(--bg-card);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    margin-bottom: var(--spacing-md);
}

.challenge-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 10px;
}

.challenge-icon {
    font-size: 20px;
}

.challenge-title {
    font-size: 16px;
    font-weight: 700;
    color: var(--text-primary);
}

.challenge-bonus {
    margin-left: auto;
    background: rgba(241, 196, 15, 0.15);
    color: #ffd86b;
    padding: 3px 10px;
    border-radius: var(--radius-full);
    font-size: 11px;
    font-weight: 700;
}

.challenge-desc {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 4px;
}

.challenge-module {
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: 10px;
}

.challenge-progress-bar {
    height: 6px;
    background: var(--bg-tertiary, rgba(255,255,255,0.1));
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: 6px;
}

.challenge-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #ff6b6b, #e67e22);
    border-radius: var(--radius-full);
    transition: width 0.5s ease;
}

.challenge-progress-text {
    font-size: 12px;
    color: var(--text-muted);
}

.challenge-done {
    color: #5aab8a;
    font-weight: 700;
}

/* Streak Freeze Counter */
.streak-freeze-counter {
    background: var(--bg-card);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: 10px;
}

.freeze-icon {
    font-size: 24px;
}

.freeze-count {
    font-size: 20px;
    font-weight: 800;
    color: var(--color-accent, #06b6d4);
}

.freeze-label {
    font-size: 12px;
    color: var(--text-muted);
}

/* Achievements Tabs */
.achievements-tabs {
    display: flex;
    gap: 8px;
    margin-bottom: var(--spacing-lg);
    justify-content: center;
}

.tab-btn {
    background: var(--bg-card);
    border: 1px solid var(--glass-border);
    color: var(--text-secondary);
    padding: 10px 24px;
    border-radius: var(--radius-full);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
}

.tab-btn:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.tab-btn.active {
    background: linear-gradient(135deg, rgba(241, 196, 15, 0.2), rgba(230, 126, 34, 0.1));
    border-color: rgba(241, 196, 15, 0.4);
    color: #ffd86b;
}

/* Login Reward Modal */
.login-reward-modal {
    text-align: center;
    max-width: 480px;
    padding: var(--spacing-lg);
}

.login-reward-header {
    margin-bottom: var(--spacing-lg);
}

.login-reward-icon {
    font-size: 56px;
    margin-bottom: 8px;
}

.login-reward-header h2 {
    color: var(--text-primary);
    margin: 0 0 4px;
    font-size: 24px;
}

.login-reward-header p {
    color: var(--text-secondary);
    margin: 0;
    font-size: 14px;
}

.login-reward-schedule {
    display: flex;
    gap: 6px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: var(--spacing-lg);
}

.login-day {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 8px 10px;
    border-radius: var(--radius-lg);
    background: var(--bg-primary);
    border: 1px solid var(--glass-border);
    min-width: 56px;
    opacity: 0.5;
}

.login-day.current {
    opacity: 1;
    border-color: rgba(241, 196, 15, 0.5);
    background: rgba(241, 196, 15, 0.1);
    box-shadow: 0 0 12px rgba(241, 196, 15, 0.2);
}

.login-day.past {
    opacity: 0.7;
    border-color: rgba(90, 171, 138, 0.3);
}

.login-day-icon {
    font-size: 20px;
}

.login-day-label {
    font-size: 10px;
    color: var(--text-muted);
    font-weight: 600;
}

.login-day-xp {
    font-size: 11px;
    color: #ffd86b;
    font-weight: 700;
}

.login-reward-claimed {
    background: linear-gradient(135deg, rgba(241, 196, 15, 0.15), rgba(230, 126, 34, 0.08));
    border: 1px solid rgba(241, 196, 15, 0.3);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

.login-xp-amount {
    font-size: 28px;
    font-weight: 800;
    color: #ffd86b;
}

.login-xp-label {
    font-size: 12px;
    color: var(--text-muted);
}

.login-freeze-earned {
    background: rgba(6, 182, 212, 0.12);
    border: 1px solid rgba(6, 182, 212, 0.3);
    border-radius: var(--radius-lg);
    padding: 10px;
    margin-bottom: var(--spacing-md);
    color: #06b6d4;
    font-size: 14px;
    font-weight: 600;
}

.login-freeze-count {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: var(--spacing-md);
}

.login-close-btn {
    margin-top: var(--spacing-sm);
}

/* Responsive */
@media (max-width: 768px) {
    .missions-challenge-row {
        grid-template-columns: 1fr;
    }

    .missions-sidebar {
        order: -1;
    }

    .login-reward-schedule {
        gap: 4px;
    }

    .login-day {
        min-width: 48px;
        padding: 6px 8px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .missions-claimable-badge {
        animation: none;
    }

    .mission-progress-fill,
    .challenge-progress-fill {
        transition: none;
    }
}