/* Base Styles and Variables */
:root {
    /* Default Theme Colors */
    --primary-color: #6a9eff;
    --secondary-color: #ff9eb7;
    --accent-color: #ffd166;
    --background-color: #f8f9fa;
    --card-background: #ffffff;
    --text-color: #333333;
    --border-color: #e0e0e0;
    --shadow-color: rgba(0, 0, 0, 0.1);
    --success-color: #4caf50;
    --danger-color: #f44336;
    --xp-gradient-start: #a1e3a1;
    --xp-gradient-end: #4caf50;
    
    /* UI Elements */
    --border-radius: 1rem;
    --box-shadow: 0 4px 12px var(--shadow-color);
    --transition-speed: 0.3s;
}

/* Dark Theme */
.theme-dark {
    --primary-color: #4a6fa5;
    --secondary-color: #bb6b8d;
    --accent-color: #c9a227;
    --background-color: #121212;
    --card-background: #1e1e1e;
    --text-color: #e0e0e0;
    --border-color: #333333;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --success-color: #388e3c;
    --danger-color: #d32f2f;
    --xp-gradient-start: #388e3c;
    --xp-gradient-end: #1b5e20;
}

/* Neon Theme */
.theme-neon {
    --primary-color: #00ffff;
    --secondary-color: #ff00ff;
    --accent-color: #ffff00;
    --background-color: #0a0a0a;
    --card-background: #121212;
    --text-color: #ffffff;
    --border-color: #333333;
    --shadow-color: rgba(0, 0, 0, 0.5);
    --success-color: #00ff00;
    --danger-color: #ff0000;
    --xp-gradient-start: #00ff00;
    --xp-gradient-end: #00aa00;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    transition: background-color var(--transition-speed), color var(--transition-speed);
    min-height: 100vh;
}

.app-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem;
}

/* Header Styles */
.app-header {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    margin-bottom: 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.app-title h1 {
    font-size: 1.8rem;
    color: var(--primary-color);
}

.user-level {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    min-width: 200px;
}

.level-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.level-number {
    font-weight: bold;
    color: var(--primary-color);
}

.level-title {
    color: var(--secondary-color);
}

.xp-container {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.xp-bar {
    height: 10px;
    background-color: var(--border-color);
    border-radius: 5px;
    overflow: hidden;
}

.xp-progress {
    height: 100%;
    width: 0%;
    background: linear-gradient(to right, var(--xp-gradient-start), var(--xp-gradient-end));
    border-radius: 5px;
    transition: width 0.5s ease-out;
}

.xp-text {
    font-size: 0.8rem;
    text-align: right;
}

/* Content Layout */
.content-wrapper {
    display: flex;
    gap: 1.5rem;
}

/* Sidebar Styles */
.sidebar {
    flex: 0 0 250px;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.achievements-panel,
.theme-selector,
.settings-panel {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

.achievements-panel h2,
.theme-selector h2,
.settings-panel h2 {
    margin-bottom: 1rem;
    font-size: 1.2rem;
    color: var(--primary-color);
}

.achievements-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.achievement-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem;
    background-color: var(--background-color);
    border-radius: 0.5rem;
    transition: transform 0.2s;
}

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

.achievement-icon {
    color: var(--accent-color);
    font-size: 1.2rem;
}

.empty-achievements,
.empty-tasks {
    color: var(--text-color);
    opacity: 0.7;
    font-style: italic;
    text-align: center;
}

.theme-options {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.theme-btn {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem;
    background-color: var(--background-color);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
}

.theme-btn:hover:not(.locked) {
    transform: translateY(-2px);
}

.theme-btn.active {
    border-color: var(--primary-color);
    background-color: rgba(var(--primary-color-rgb), 0.1);
}

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

.theme-color {
    width: 20px;
    height: 20px;
    border-radius: 50%;
}

.theme-btn[data-theme="default"] .theme-color {
    background: linear-gradient(135deg, #6a9eff, #ff9eb7, #ffd166);
}

.theme-btn[data-theme="dark"] .theme-color {
    background: linear-gradient(135deg, #4a6fa5, #bb6b8d, #121212);
}

.theme-btn[data-theme="neon"] .theme-color {
    background: linear-gradient(135deg, #00ffff, #ff00ff, #ffff00);
}

.fa-lock {
    margin-left: auto;
    color: var(--text-color);
    opacity: 0.7;
}

.unlock-info {
    position: absolute;
    top: -30px;
    left: 50%;
    transform: translateX(-50%);
    background-color: var(--card-background);
    padding: 0.5rem;
    border-radius: 0.5rem;
    box-shadow: var(--box-shadow);
    font-size: 0.8rem;
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: all 0.2s;
    z-index: 10;
}

.theme-btn.locked:hover .unlock-info {
    opacity: 1;
    visibility: visible;
    top: -40px;
}

.setting-option {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

/* Switch Toggle */
.switch {
    position: relative;
    display: inline-block;
    width: 50px;
    height: 24px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--border-color);
    transition: .4s;
}

.slider:before {
    position: absolute;
    content: "";
    height: 16px;
    width: 16px;
    left: 4px;
    bottom: 4px;
    background-color: white;
    transition: .4s;
}

input:checked + .slider {
    background-color: var(--primary-color);
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.slider.round {
    border-radius: 34px;
}

.slider.round:before {
    border-radius: 50%;
}

.danger-btn {
    background-color: var(--danger-color);
    color: white;
    border: none;
    padding: 0.75rem;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
    width: 100%;
    margin-top: 1rem;
}

.danger-btn:hover {
    opacity: 0.9;
}

/* Main Content Styles */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.task-input-container {
    display: flex;
    gap: 0.5rem;
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
}

#task-input {
    flex: 1;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    background-color: var(--background-color);
    color: var(--text-color);
}

#task-difficulty {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    background-color: var(--background-color);
    color: var(--text-color);
}

#add-task-btn {
    padding: 0.75rem 1.5rem;
    background-color: var(--primary-color);
    color: white;
    border: none;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
}

#add-task-btn:hover {
    opacity: 0.9;
}

.task-filters {
    display: flex;
    gap: 0.5rem;
}

.filter-btn {
    padding: 0.5rem 1rem;
    background-color: var(--card-background);
    border: 1px solid var(--border-color);
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
}

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

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

.tasks-container {
    background-color: var(--card-background);
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    min-height: 300px;
}

.task-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem;
    background-color: var(--background-color);
    border-radius: 0.5rem;
    margin-bottom: 0.75rem;
    transition: all 0.2s;
}

.task-item:hover {
    transform: translateY(-2px);
    box-shadow: 0 2px 8px var(--shadow-color);
}

.task-checkbox {
    width: 20px;
    height: 20px;
    cursor: pointer;
}

.task-content {
    flex: 1;
}

.task-name {
    margin-bottom: 0.25rem;
}

.task-difficulty {
    font-size: 0.8rem;
    padding: 0.25rem 0.5rem;
    border-radius: 0.25rem;
    display: inline-block;
}

.task-difficulty.easy {
    background-color: rgba(76, 175, 80, 0.2);
    color: var(--success-color);
}

.task-difficulty.medium {
    background-color: rgba(255, 209, 102, 0.2);
    color: var(--accent-color);
}

.task-difficulty.hard {
    background-color: rgba(244, 67, 54, 0.2);
    color: var(--danger-color);
}

.task-actions {
    display: flex;
    gap: 0.5rem;
}

.task-btn {
    background: none;
    border: none;
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-color);
    opacity: 0.7;
    transition: all 0.2s;
}

.task-btn:hover {
    opacity: 1;
}

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

.delete-btn:hover {
    color: var(--danger-color);
}

.task-item.completed .task-name {
    text-decoration: line-through;
    opacity: 0.7;
}

/* Popup Styles */
.achievement-popup,
.level-up-popup {
    position: fixed;
    top: 20px;
    right: 20px;
    background-color: var(--card-background);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 1.5rem;
    z-index: 100;
    transform: translateX(150%);
    transition: transform 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.achievement-popup.show,
.level-up-popup.show {
    transform: translateX(0);
}

.achievement-content,
.level-up-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    text-align: center;
}

.achievement-icon {
    font-size: 2rem;
    color: var(--accent-color);
}

#confetti-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: -1;
}

/* Responsive Styles */
@media (max-width: 768px) {
    .content-wrapper {
        flex-direction: column;
    }
    
    .sidebar {
        flex: none;
        width: 100%;
    }
    
    .app-header {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .user-level {
        width: 100%;
    }
    
    .task-input-container {
        flex-direction: column;
    }
}