/* PhysicsQuest - Main Stylesheet */

/* ===== GLOBAL STYLES ===== */
:root {
    /* Primary Colors */
    --primary-color: #58cc02;
    --primary-dark: #46a302;
    --primary-light: #89e219;
    
    /* Secondary Colors */
    --secondary-color: #1cb0f6;
    --secondary-dark: #0c8ad0;
    --secondary-light: #61c9fa;
    
    /* Accent Colors */
    --accent-color: #ff4b4b;
    --accent-dark: #ea2b2b;
    --accent-light: #ff7a7a;
    
    /* Neutral Colors */
    --neutral-100: #ffffff;
    --neutral-200: #f7f7f7;
    --neutral-300: #e5e5e5;
    --neutral-400: #d1d1d1;
    --neutral-500: #afafaf;
    --neutral-600: #777777;
    --neutral-700: #4b4b4b;
    --neutral-800: #2b2b2b;
    --neutral-900: #111111;
    
    /* Island Colors */
    --island-1-color: #1cb0f6;
    --island-2-color: #ff9600;
    --island-3-color: #ce82ff;
    --island-4-color: #ff4b4b;
    --island-5-color: #2ccc71;
    
    /* Functional Colors */
    --correct-color: #58cc02;
    --incorrect-color: #ff4b4b;
    --locked-color: #afafaf;
    
    /* Shadows */
    --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.12);
    --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.14);
    
    /* Border Radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    /* Spacing */
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-xxl: 48px;
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

html, body {
    font-family: 'Nunito', sans-serif;
    font-size: 16px;
    line-height: 1.5;
    color: var(--neutral-800);
    background-color: var(--neutral-200);
    height: 100%;
    overflow: hidden;
}

.hidden {
    display: none !important;
}

/* ===== APP CONTAINER ===== */
.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-width: 100%;
    margin: 0 auto;
    background-color: var(--neutral-100);
    position: relative;
    overflow: hidden;
}

/* ===== HEADER STYLES ===== */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--space-md);
    background-color: var(--neutral-100);
    box-shadow: var(--shadow-sm);
    z-index: 10;
    height: 60px;
}

.header-left, .header-right, .header-center {
    display: flex;
    align-items: center;
}

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

.logo img {
    height: 32px;
    width: auto;
}

.logo h1 {
    font-size: 1.2rem;
    font-weight: 800;
    color: var(--primary-color);
}

.streak-counter, .xp-counter, .hearts-container {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    margin: 0 var(--space-md);
    font-weight: 700;
}

.streak-counter i {
    color: var(--accent-color);
}

.xp-counter i {
    color: var(--secondary-color);
}

.hearts-container i {
    color: var(--accent-color);
}

.profile-icon img {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
}

.profile-picture {
    width: 80px;
    height: 80px;
    border-radius: 50%;
}

.profile-img-small {
    width: 32px;
    height: 32px;
    border-radius: 50%;
}

/* ===== MAIN CONTENT STYLES ===== */
.main-content {
    flex: 1;
    overflow-y: auto;
    position: relative;
    padding-bottom: 70px; /* Prevent content from being hidden behind the fixed nav */
}

.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow-y: auto;
    background-color: var(--neutral-100);
    padding: var(--space-lg);
    /* Extra bottom space ensures content isn't hidden behind the nav bar */
    padding-bottom: calc(var(--space-lg) + 6rem);
    transition: transform var(--transition-normal), opacity var(--transition-normal);
}

/* ===== WELCOME SCREEN ===== */
.welcome-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    height: 100%;
    gap: var(--space-xl);
}

.welcome-container h2 {
    font-size: 2.5rem;
    font-weight: 800;
    color: var(--primary-color);
}

.welcome-container p {
    font-size: 1.2rem;
    color: var(--neutral-700);
    max-width: 600px;
}

/* ===== HOME SCREEN (ISLANDS MAP) ===== */
.islands-container {
    padding: var(--space-md);
}

.islands-container h2 {
    font-size: 1.5rem;
    margin-bottom: var(--space-lg);
    text-align: center;
}

.islands-map {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--space-xl);
    max-width: 1200px;
    margin: 0 auto;
}

.island {
    background-color: var(--neutral-100);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    box-shadow: var(--shadow-md);
    text-align: center;
    transition: transform var(--transition-fast);
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.island:hover {
    transform: translateY(-5px);
}

.island::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 8px;
    background-color: var(--island-1-color);
}

.island#island-1::before { background-color: var(--island-1-color); }
.island#island-2::before { background-color: var(--island-2-color); }
.island#island-3::before { background-color: var(--island-3-color); }
.island#island-4::before { background-color: var(--island-4-color); }
.island#island-5::before { background-color: var(--island-5-color); }

.island-icon {
    font-size: 2.5rem;
    margin-bottom: var(--space-md);
}

.island#island-1 .island-icon { color: var(--island-1-color); }
.island#island-2 .island-icon { color: var(--island-2-color); }
.island#island-3 .island-icon { color: var(--island-3-color); }
.island#island-4 .island-icon { color: var(--island-4-color); }
.island#island-5 .island-icon { color: var(--island-5-color); }

.island h3 {
    font-size: 1.2rem;
    margin-bottom: var(--space-md);
}

.progress-bar {
    height: 8px;
    background-color: var(--neutral-300);
    border-radius: var(--radius-sm);
    margin-bottom: var(--space-sm);
    overflow: hidden;
}

.progress {
    height: 100%;
    background-color: var(--primary-color);
    transition: width var(--transition-normal);
}

.progress-text {
    font-size: 0.9rem;
    color: var(--neutral-600);
}

.island.locked {
    opacity: 0.7;
    cursor: not-allowed;
}

.lock-icon {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 3rem;
    color: var(--neutral-600);
    background-color: rgba(255, 255, 255, 0.8);
    border-radius: 50%;
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ===== SKILLS SCREEN ===== */
.skills-header {
    display: flex;
    align-items: center;
    margin-bottom: var(--space-lg);
}

.back-button {
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--neutral-700);
    cursor: pointer;
    margin-right: var(--space-md);
}

.skills-container {
    max-width: 800px;
    margin: 0 auto;
}

#skills-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.skill-item {
    background-color: var(--neutral-100);
    border-radius: var(--radius-lg);
    padding: var(--space-lg);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    cursor: pointer;
    transition: transform var(--transition-fast);
    position: relative;
    overflow: hidden;
}

.skill-item:hover {
    transform: translateY(-3px);
}

.skill-icon {
    font-size: 2rem;
    margin-right: var(--space-lg);
    width: 60px;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background-color: var(--primary-light);
    color: var(--neutral-100);
}

.skill-info {
    flex: 1;
}

.skill-info h3 {
    font-size: 1.2rem;
    margin-bottom: var(--space-xs);
}

.skill-info p {
    font-size: 0.9rem;
    color: var(--neutral-600);
}

.skill-level {
    display: flex;
    gap: var(--space-xs);
    margin-left: var(--space-md);
}

.level-circle {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background-color: var(--neutral-300);
}

.level-circle.filled {
    background-color: var(--primary-color);
}

.skill-item.locked {
    opacity: 0.7;
    cursor: not-allowed;
}

.skill-item.locked .skill-icon {
    background-color: var(--neutral-400);
}

/* ===== LESSON SCREEN ===== */
.lesson-header {
    padding: var(--space-md);
    border-bottom: 1px solid var(--neutral-300);
}

.lesson-progress {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.lesson-progress .progress-bar {
    flex: 1;
    margin-right: var(--space-md);
    height: 12px;
}

.hearts-display {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    font-weight: 700;
}

.hearts-display i {
    color: var(--accent-color);
}

.lesson-content {
    padding: var(--space-xl);
    max-width: 800px;
    margin: 0 auto;
}

#question-container {
    margin-bottom: var(--space-xl);
}

.question-prompt {
    margin-bottom: var(--space-lg);
}

.question-text {
    font-size: 1.5rem;
    line-height: 1.4;
}

/* Multiple Choice Question */
.options-container {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.option-item {
    background-color: var(--neutral-200);
    border: 2px solid var(--neutral-300);
    border-radius: var(--radius-md);
    padding: var(--space-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.option-item:hover {
    background-color: var(--neutral-300);
}

.option-item.selected {
    background-color: var(--secondary-light);
    border-color: var(--secondary-color);
}

.option-item.correct {
    background-color: var(--correct-color);
    border-color: var(--primary-dark);
    color: var(--neutral-100);
}

.option-item.incorrect {
    background-color: var(--incorrect-color);
    border-color: var(--accent-dark);
    color: var(--neutral-100);
}

/* Fill in the Blank Question */
.fill-blank-container {
    margin-top: var(--space-lg);
}

.blank-input {
    width: 100%;
    padding: var(--space-md);
    font-size: 1.2rem;
    border: 2px solid var(--neutral-400);
    border-radius: var(--radius-md);
    outline: none;
    transition: border-color var(--transition-fast);
}

.blank-input:focus {
    border-color: var(--secondary-color);
}

/* Matching Question */
.matching-container {
    display: flex;
    justify-content: space-between;
    gap: var(--space-xl);
}

.matching-items-left, .matching-items-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.matching-item {
    background-color: var(--neutral-200);
    border: 2px solid var(--neutral-300);
    border-radius: var(--radius-md);
    padding: var(--space-md);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.matching-item:hover {
    background-color: var(--neutral-300);
}

.matching-item.selected {
    background-color: var(--secondary-light);
    border-color: var(--secondary-color);
}

.matching-item.matched {
    background-color: var(--correct-color);
    border-color: var(--primary-dark);
    color: var(--neutral-100);
}

/* Unit Conversion Question */
.conversion-container {
    margin-top: var(--space-lg);
}

.conversion-input {
    display: flex;
    gap: var(--space-md);
}

.conversion-value {
    flex: 1;
    padding: var(--space-md);
    font-size: 1.2rem;
    border: 2px solid var(--neutral-400);
    border-radius: var(--radius-md);
    outline: none;
}

.conversion-unit {
    padding: var(--space-md);
    font-size: 1.2rem;
    border: 2px solid var(--neutral-400);
    border-radius: var(--radius-md);
    outline: none;
    background-color: var(--neutral-200);
}

.lesson-footer {
    padding: var(--space-md);
    border-top: 1px solid var(--neutral-300);
    display: flex;
    justify-content: center;
}

/* ===== FEEDBACK SCREEN ===== */
.feedback-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    text-align: center;
    padding: var(--space-xl);
}

.feedback-result {
    margin-bottom: var(--space-xl);
}

.feedback-icon {
    font-size: 5rem;
    margin-bottom: var(--space-lg);
}

.feedback-icon.correct {
    color: var(--correct-color);
}

.feedback-icon.incorrect {
    color: var(--incorrect-color);
}

.feedback-container h2 {
    font-size: 2rem;
    margin-bottom: var(--space-md);
}

.feedback-container p {
    font-size: 1.2rem;
    color: var(--neutral-700);
    max-width: 600px;
    margin-bottom: var(--space-lg);
}

.correct-answer {
    background-color: var(--neutral-200);
    padding: var(--space-lg);
    border-radius: var(--radius-md);
    margin-top: var(--space-lg);
    text-align: left;
}

.correct-answer h3 {
    font-size: 1rem;
    color: var(--neutral-700);
    margin-bottom: var(--space-sm);
}

.correct-answer p {
    font-size: 1.1rem;
    color: var(--primary-dark);
    margin-bottom: 0;
}

/* ===== LESSON COMPLETE SCREEN ===== */
.complete-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    text-align: center;
    padding: var(--space-xl);
}

.complete-header {
    margin-bottom: var(--space-xl);
}

.complete-header i {
    font-size: 5rem;
    color: var(--primary-color);
    margin-bottom: var(--space-md);
}

.complete-header h2 {
    font-size: 2.5rem;
    color: var(--primary-color);
}

.stats-container {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
    margin-bottom: var(--space-xl);
}

.stat-item {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    font-size: 1.2rem;
}

.stat-item i {
    font-size: 1.5rem;
}

.stat-item i.fa-star {
    color: var(--secondary-color);
}

.stat-item i.fa-check-circle {
    color: var(--correct-color);
}

.buttons-container {
    display: flex;
    gap: var(--space-md);
}

/* ===== PRACTICE, LEADERBOARD, PROFILE ===== */
.practice-container,
.leaderboard-container,
.profile-container,
.help-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-xl);
    text-align: center;
}

.leaderboard-list {
    width: 100%;
    max-width: 320px;
}
.leaderboard-entry {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    margin: var(--space-xs) 0;
}
.leaderboard-entry img {
    width: 32px;
    height: 32px;
    border-radius: 50%;
}
.leaderboard-rank {
    width: 24px;
    text-align: right;
    font-weight: 700;
}
.leaderboard-xp {
    margin-left: auto;
}

/* ===== NAVIGATION BAR ===== */
.nav-bar {
    display: flex;
    justify-content: space-around;
    align-items: center;
    background-color: var(--neutral-100);
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    padding: var(--space-sm) 0 calc(var(--space-sm) + env(safe-area-inset-bottom)) 0;
    z-index: 10;
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--space-sm);
    cursor: pointer;
    color: var(--neutral-600);
    transition: color var(--transition-fast);
}

.nav-item i {
    font-size: 1.5rem;
    margin-bottom: var(--space-xs);
}

.nav-item span {
    font-size: 0.8rem;
}

.nav-item.active {
    color: var(--primary-color);
}

/* ===== BUTTONS ===== */
.primary-button {
    background-color: var(--primary-color);
    color: var(--neutral-100);
    border: none;
    border-radius: var(--radius-md);
    padding: var(--space-md) var(--space-xl);
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: background-color var(--transition-fast);
    box-shadow: 0 4px 0 var(--primary-dark);
}

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

.primary-button:active {
    transform: translateY(2px);
    box-shadow: 0 2px 0 var(--primary-dark);
}

.primary-button.disabled {
    background-color: var(--neutral-400);
    box-shadow: 0 4px 0 var(--neutral-600);
    cursor: not-allowed;
}

.secondary-button {
    background-color: var(--neutral-200);
    color: var(--neutral-700);
    border: 2px solid var(--neutral-400);
    border-radius: var(--radius-md);
    padding: var(--space-md) var(--space-xl);
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.secondary-button:hover {
    background-color: var(--neutral-300);
    border-color: var(--neutral-500);
}

.secondary-button.disabled {
    background-color: var(--neutral-200);
    color: var(--neutral-500);
    border-color: var(--neutral-400);
    cursor: not-allowed;
}

/* ===== ANIMATIONS ===== */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideInUp {
    from {
        transform: translateY(20px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

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

.fade-in {
    animation: fadeIn var(--transition-normal);
}

.slide-in-up {
    animation: slideInUp var(--transition-normal);
}

.pulse {
    animation: pulse 1.5s infinite;
}

/* ===== RESPONSIVE STYLES ===== */
@media (max-width: 768px) {
    .islands-map {
        grid-template-columns: 1fr;
        gap: var(--space-lg);
    }
    
    .matching-container {
        flex-direction: column;
    }
    
    .lesson-content {
        padding: var(--space-md);
    }
    
    .question-text {
        font-size: 1.3rem;
    }
    
    .buttons-container {
        flex-direction: column;
    }
    
    .header-center {
        display: none;
    }
}

@media (max-width: 480px) {
    .app-header {
        padding: var(--space-sm);
    }
    
    .logo h1 {
        font-size: 1rem;
    }
    
    .logo img {
        height: 24px;
    }
    
    .hearts-container, .profile-icon {
        margin: 0 var(--space-sm);
    }
    
    .lesson-content {
        padding: var(--space-sm);
    }
    
    .question-text {
        font-size: 1.1rem;
    }
    
    .complete-header h2 {
        font-size: 1.8rem;
    }
    
    .stat-item {
        font-size: 1rem;
    }
    
    .nav-item i {
        font-size: 1.2rem;
    }

    .nav-item span {
        font-size: 0.7rem;
    }
}

/* Placeholder screens */
#practice-screen,
#leaderboard-screen,
#profile-screen {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
}

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

/* Help screen code styling */
.help-container code {
    background-color: var(--neutral-200);
    padding: 2px 4px;
    border-radius: var(--radius-sm);
}