/* ADHD Friendly Premium Design - Light Mindful Green Theme */
:root {
    --bg-color: #f0fdf4;
    --container-bg: rgba(255, 255, 255, 0.85);
    --text-primary: #064e3b;
    --text-secondary: #047857;
    --accent-color: #10b981;
    --accent-hover: #059669;
    --success-color: #10b981;
    --glass-border: rgba(16, 185, 129, 0.2);
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    background-image: radial-gradient(circle at 50% 0%, #d1fae5 0%, var(--bg-color) 70%);
    background-attachment: fixed;
    color: var(--text-primary);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 24px;
}

/* Tabs */
.tabs-container {
    display: flex;
    gap: 16px;
    background: var(--container-bg);
    padding: 8px;
    border-radius: 100px;
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(16px);
    margin-bottom: 32px;
    z-index: 10;
    box-shadow: 0 4px 20px rgba(16, 185, 129, 0.05);
}

.tab-btn {
    background: transparent;
    color: var(--text-secondary);
    border: none;
    padding: 12px 24px;
    border-radius: 100px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
}

.tab-btn:hover {
    color: var(--text-primary);
    background: rgba(16, 185, 129, 0.1);
}

.tab-btn.active {
    background: var(--accent-color);
    color: white;
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.3);
}

/* Layout */
.app-wrapper {
    width: 100%;
    max-width: 1200px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.view-section {
    width: 100%;
    display: none;
    animation: fadeIn 0.4s ease-out;
}

.view-section.active {
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* Common Header */
header {
    text-align: center;
    margin-bottom: 32px;
    width: 100%;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    background: linear-gradient(to right, #047857, #10b981);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 8px;
}

header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

/* Progress Bar */
.progress-wrapper {
    width: 100%;
    max-width: 600px;
    margin: 24px auto 0;
    background: var(--container-bg);
    padding: 16px 24px;
    border-radius: 20px;
    border: 1px solid var(--glass-border);
    backdrop-filter: blur(16px);
    box-shadow: 0 10px 30px rgba(16, 185, 129, 0.05);
}

.progress-text {
    display: flex;
    justify-content: space-between;
    margin-bottom: 12px;
    font-weight: 600;
    font-size: 1rem;
}

#progress-percentage {
    color: var(--success-color);
}

.progress-bar-container {
    width: 100%;
    height: 12px;
    background: rgba(16, 185, 129, 0.15);
    border-radius: 100px;
    overflow: hidden;
    border: 1px solid var(--glass-border);
}

.progress-bar-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-hover), var(--success-color));
    width: 0%;
    border-radius: 100px;
    transition: width 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.3);
}

/* Habit Grid */
.habit-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 24px;
    width: 100%;
}

.day-card {
    background: var(--container-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 24px;
    transition: transform 0.2s, box-shadow 0.2s;
    box-shadow: 0 10px 30px -10px rgba(16, 185, 129, 0.1);
}

.day-card.locked-past {
    opacity: 0.7;
    filter: grayscale(0.2);
}

.day-card.locked-future {
    opacity: 0.5;
}

.day-card.current-day {
    transform: scale(1.02);
    box-shadow: 0 15px 35px rgba(16, 185, 129, 0.25);
    border: 2px solid var(--accent-color);
}

.day-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 40px -10px rgba(16, 185, 129, 0.2);
    border-color: rgba(16, 185, 129, 0.4);
}

.day-card.perfect-day {
    border-color: rgba(16, 185, 129, 0.6);
    background: linear-gradient(135deg, var(--container-bg) 0%, rgba(16, 185, 129, 0.1) 100%);
    box-shadow: 0 10px 30px rgba(16, 185, 129, 0.2);
}

.day-header {
    border-bottom: 1px solid var(--glass-border);
    padding-bottom: 16px;
    margin-bottom: 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.day-title {
    font-size: 1.2rem;
    font-weight: 800;
}

.day-date {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.habit-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.habit-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.habit-name {
    font-size: 1.05rem;
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-primary);
}

/* Custom Checkbox Shared */
.checkbox-container {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    border: 2px solid var(--text-secondary);
    background: white;
    cursor: pointer;
    transition: all 0.2s;
    position: relative;
    flex-shrink: 0;
}

.checkbox-container.checked {
    background: var(--success-color);
    border-color: var(--success-color);
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.3);
}

.checkbox-container::after {
    content: '';
    position: absolute;
    width: 6px;
    height: 12px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
    opacity: 0;
    transition: opacity 0.2s;
}

.checkbox-container.checked::after {
    opacity: 1;
}

/* To-Do Specific */
.app-container {
    width: 100%;
    max-width: 500px;
    background: var(--container-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 32px;
    box-shadow: 0 25px 50px -12px rgba(16, 185, 129, 0.15);
}

.input-container {
    display: flex;
    gap: 12px;
    margin-bottom: 32px;
}

input[type="text"] {
    flex: 1;
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 16px;
    color: var(--text-primary);
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

input[type="text"]:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.2);
}

input[type="text"]::placeholder {
    color: #9ca3af;
}

button#add-btn {
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: 12px;
    padding: 0 24px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s, box-shadow 0.2s;
    box-shadow: 0 4px 12px rgba(16, 185, 129, 0.2);
}

button#add-btn:hover {
    background: var(--accent-hover);
    box-shadow: 0 6px 16px rgba(16, 185, 129, 0.3);
}

button#add-btn:active {
    transform: scale(0.95);
}

ul#todo-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

ul#todo-list li {
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 16px;
    display: flex;
    align-items: center;
    gap: 16px;
    transition: all 0.3s ease;
    animation: fadeIn 0.3s ease-out;
    box-shadow: 0 2px 8px rgba(16, 185, 129, 0.05);
}

ul#todo-list li.completed {
    opacity: 0.6;
    background: rgba(16, 185, 129, 0.05);
    border-color: rgba(16, 185, 129, 0.2);
    box-shadow: none;
}

ul#todo-list li.completed .task-text {
    text-decoration: line-through;
    color: var(--text-secondary);
}

.task-text {
    flex: 1;
    font-size: 1.1rem;
    transition: color 0.3s;
    word-break: break-word;
    color: var(--text-primary);
}

.delete-btn {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    font-size: 1.2rem;
    opacity: 0.5;
    transition: opacity 0.2s, color 0.2s, background-color 0.2s;
    padding: 4px;
    border-radius: 4px;
}

.delete-btn:hover {
    opacity: 1;
    color: #ef4444;
    background: rgba(239, 68, 68, 0.1);
}

.reset-container {
    margin-top: 48px;
    text-align: center;
    padding-bottom: 48px;
}

#reset-challenge-btn {
    background: white;
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #ef4444;
    padding: 10px 20px;
    border-radius: 100px;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.9rem;
    box-shadow: 0 4px 12px rgba(239, 68, 68, 0.05);
}

#reset-challenge-btn:hover {
    background: rgba(239, 68, 68, 0.05);
    border-color: #ef4444;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}