/* ===== RESET & BASE STYLES ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Light Theme Colors - Eco-friendly Palette */
    --primary: #2ecc71;
    --primary-dark: #27ae60;
    --primary-light: #58d68d;
    --secondary: #3498db;
    --secondary-dark: #2980b9;
    --accent: #e74c3c;
    --accent-dark: #c0392b;
    --warning: #f39c12;
    --warning-dark: #d68910;
    --success: #27ae60;

    /* Weightage Colors */
    --weight-high: #e74c3c;
    --weight-medium: #f39c12;
    --weight-low: #2ecc71;

    /* Priority Colors */
    --priority-high: #e74c3c;
    --priority-medium: #f39c12;
    --priority-low: #2ecc71;

    /* Backgrounds */
    --bg-primary: #f8f9fa;
    --bg-secondary: #ffffff;
    --bg-tertiary: #e9ecef;
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.18);

    /* Text */
    --text-primary: #2c3e50;
    --text-secondary: #7f8c8d;
    --text-light: #bdc3c7;
    --text-on-primary: #ffffff;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-xxl: 3rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-full: 50%;

    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.2);
    --shadow-glow: 0 0 20px rgba(46, 204, 113, 0.3);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, #d5f4e6 100%);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    overflow-x: hidden;
    transition: background var(--transition-normal), color var(--transition-normal);
}

/* ===== LAYOUT ===== */
.app-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-md);
}

/* ===== PRELOADER ===== */
.preloader {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.5s ease;
}

.preloader.hidden {
    opacity: 0;
    pointer-events: none;
}

.loader {
    text-align: center;
    color: white;
}

.book {
    display: flex;
    gap: 5px;
    margin-bottom: var(--spacing-md);
    justify-content: center;
}

.page {
    width: 30px;
    height: 40px;
    background: white;
    border-radius: 2px;
    animation: bookFlip 1.5s ease-in-out infinite;
}

.page:nth-child(2) {
    animation-delay: 0.2s;
}

.page:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes bookFlip {
    0%, 100% {
        transform: rotateY(0deg);
    }
    50% {
        transform: rotateY(-180deg);
    }
}

.loader .text {
    font-size: 1.2rem;
    font-weight: 500;
    letter-spacing: 2px;
    animation: fadeInOut 1.5s ease-in-out infinite;
}

@keyframes fadeInOut {
    0%, 100% { opacity: 0.5; }
    50% { opacity: 1; }
}

/* ===== HEADER ===== */
.header {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-md) var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: var(--spacing-md);
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-dark);
}

.logo i {
    font-size: 2rem;
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.nav-tabs {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.tab-btn {
    background: transparent;
    border: 2px solid transparent;
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-lg);
    cursor: pointer;
    font-family: inherit;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all var(--transition-normal);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.tab-btn:hover {
    background: rgba(46, 204, 113, 0.1);
    color: var(--primary);
    transform: translateY(-2px);
}

.tab-btn.active {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    border-color: var(--primary);
    box-shadow: var(--shadow-glow);
}

.header-actions {
    display: flex;
    gap: var(--spacing-sm);
}

.icon-btn {
    background: var(--bg-secondary);
    border: none;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    color: var(--text-secondary);
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-sm);
}

.icon-btn:hover {
    background: var(--primary);
    color: white;
    transform: scale(1.1);
    box-shadow: var(--shadow-glow);
}

/* ===== MAIN CONTENT ===== */
.main-content {
    min-height: calc(100vh - 200px);
}

.tab-content {
    display: none;
    animation: fadeIn var(--transition-normal);
}

.tab-content.active {
    display: block;
}

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

/* ===== DASHBOARD ===== */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: var(--spacing-lg);
}

.stat-card {
    padding: var(--spacing-lg);
    border-radius: var(--radius-xl);
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.stat-card.full-width {
    grid-column: 1 / -1;
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 2px solid var(--bg-tertiary);
}

.card-header h2 {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-primary);
}

.card-header h2 i {
    color: var(--primary);
}

/* Progress Circle */
.progress-circle-container {
    position: relative;
    width: 180px;
    height: 180px;
    margin: var(--spacing-lg) auto;
}

.progress-circle {
    transform: rotate(-90deg);
    width: 100%;
    height: 100%;
}

.progress-bg {
    fill: none;
    stroke: var(--bg-tertiary);
    stroke-width: 12;
}

.progress-fill {
    fill: none;
    stroke: url(#gradient);
    stroke-width: 12;
    stroke-linecap: round;
    stroke-dasharray: 565.48;
    stroke-dashoffset: 565.48;
    transition: stroke-dashoffset 1s ease;
}

.progress-text {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
}

.progress-text .percentage {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary);
    line-height: 1;
}

.progress-text .label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.stat-details {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-md);
    text-align: center;
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.stat-label {
    font-size: 0.8rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.stat-value {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--primary);
}

/* Progress Bars */
.progress-bar-container {
    margin: var(--spacing-lg) 0;
}

.progress-bar {
    height: 20px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
    position: relative;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.progress-fill-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, var(--primary-light) 100%);
    border-radius: var(--radius-full);
    transition: width 1s ease;
    position: relative;
    overflow: hidden;
}

.progress-fill-bar::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        90deg,
        transparent 0%,
        rgba(255, 255, 255, 0.4) 50%,
        transparent 100%
    );
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(100%); }
}

.progress-label {
    display: block;
    text-align: center;
    margin-top: var(--spacing-sm);
    font-weight: 600;
    color: var(--text-secondary);
}

.bg-gradient-2 {
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
}

/* Badges */
.badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: var(--radius-full);
    font-size: 0.8rem;
    font-weight: 600;
}

.badge-high {
    background: var(--weight-high);
    color: white;
}

.badge-medium {
    background: var(--weight-medium);
    color: white;
}

.badge-low {
    background: var(--weight-low);
    color: white;
}

.badge-priority {
    background: var(--priority-high);
    color: white;
}

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

/* Mini Stats */
.mini-stats {
    display: flex;
    justify-content: space-around;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--bg-tertiary);
}

.mini-stat {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.9rem;
}

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

.text-high { color: var(--weight-high); }
.text-medium { color: var(--weight-medium); }
.text-low { color: var(--weight-low); }

/* Task Summary */
.task-summary {
    display: flex;
    justify-content: space-around;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--bg-tertiary);
}

.summary-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.9rem;
}

.priority-dot {
    width: 12px;
    height: 12px;
    border-radius: var(--radius-full);
}

.priority-dot.high { background: var(--priority-high); }
.priority-dot.medium { background: var(--priority-medium); }
.priority-dot.low { background: var(--priority-low); }

/* Weekly Goals */
.week-goals {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin: var(--spacing-lg) 0;
}

.week-goal-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-sm);
    background: var(--bg-tertiary);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.week-goal-item:hover {
    background: var(--bg-secondary);
    transform: translateX(5px);
}

.week-goal-item.completed {
    opacity: 0.6;
    text-decoration: line-through;
}

.week-checkbox {
    width: 20px;
    height: 20px;
    border: 2px solid var(--primary);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.week-checkbox.checked {
    background: var(--primary);
    color: white;
}

.weekly-progress {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid var(--bg-tertiary);
}

.week-bar {
    height: 12px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: var(--spacing-sm);
}

.week-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, var(--warning) 100%);
    border-radius: var(--radius-full);
    transition: width 0.5s ease;
}

#weekly-progress-text {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Activity Feed */
.activity-feed {
    max-height: 300px;
    overflow-y: auto;
}

.activity-item {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-sm) 0;
    border-bottom: 1px solid var(--bg-tertiary);
}

.activity-item:last-child {
    border-bottom: none;
}

.activity-icon {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary);
    color: white;
    font-size: 0.9rem;
    flex-shrink: 0;
}

.activity-content {
    flex: 1;
}

.activity-text {
    font-size: 0.9rem;
    margin-bottom: var(--spacing-xs);
}

.activity-time {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.empty-state {
    text-align: center;
    color: var(--text-secondary);
    padding: var(--spacing-xl);
    font-style: italic;
}

/* ===== CHAPTERS TAB ===== */
.content-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-lg);
    flex-wrap: wrap;
    gap: var(--spacing-md);
}

.content-header h2 {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.5rem;
    font-weight: 700;
}

.filter-controls {
    display: flex;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.filter-btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border: 2px solid var(--bg-tertiary);
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    cursor: pointer;
    font-family: inherit;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
}

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

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

.chapters-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

/* Chapter Card */
.chapter-card {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.chapter-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: var(--weight-color, var(--primary));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition-normal);
}

.chapter-card:hover::before {
    transform: scaleX(1);
}

.chapter-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.chapter-card.high-weight::before { --weight-color: var(--weight-high); }
.chapter-card.medium-weight::before { --weight-color: var(--weight-medium); }
.chapter-card.low-weight::before { --weight-color: var(--weight-low); }

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

.chapter-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    padding-right: var(--spacing-md);
}

.chapter-weightage {
    display: flex;
    gap: var(--spacing-xs);
}

.weightage-badge {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-full);
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.weightage-badge.high {
    background: var(--weight-high);
    color: white;
}

.weightage-badge.medium {
    background: var(--weight-medium);
    color: white;
}

.weightage-badge.low {
    background: var(--weight-low);
    color: white;
}

.chapter-meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.chapter-meta span {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.chapter-meta i {
    color: var(--primary);
}

.chapter-progress-container {
    margin: var(--spacing-md) 0;
}

.chapter-progress-bar {
    height: 16px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
    margin-bottom: var(--spacing-xs);
}

.chapter-progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, var(--primary-light) 100%);
    border-radius: var(--radius-full);
    transition: width 0.8s ease;
    position: relative;
}

.chapter-progress-fill.animated::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(
        90deg,
        transparent 0%,
        rgba(255, 255, 255, 0.5) 50%,
        transparent 100%
    );
    animation: shimmer 1.5s infinite;
}

.chapter-progress-text {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-align: right;
}

.chapter-actions {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-md);
}

.btn-action {
    flex: 1;
    padding: var(--spacing-sm);
    background: var(--bg-tertiary);
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    font-family: inherit;
    font-weight: 500;
    color: var(--text-secondary);
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
}

.btn-action:hover {
    background: var(--primary);
    color: white;
    transform: scale(1.05);
}

.btn-action.danger:hover {
    background: var(--accent);
}

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

/* ===== TASKS TAB ===== */
.tasks-sticky-progress {
    position: sticky;
    top: 150px;
    z-index: 50;
    margin-bottom: var(--spacing-lg);
    display: flex;
    justify-content: flex-end;
    pointer-events: none;
}

.mini-progress-card {
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    pointer-events: auto;
    box-shadow: var(--shadow-lg);
    animation: slideInRight 0.5s ease;
}

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

.mini-header {
    display: flex;
    flex-direction: column;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.mini-circle {
    position: relative;
    width: 60px;
    height: 60px;
}

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

.mini-circle .bg-circle {
    fill: none;
    stroke: var(--bg-tertiary);
    stroke-width: 6;
}

.mini-circle .fill-circle {
    fill: none;
    stroke: var(--secondary);
    stroke-width: 6;
    stroke-linecap: round;
    stroke-dasharray: 251.33;
    stroke-dashoffset: 251.33;
    transition: stroke-dashoffset 0.5s ease;
}

.mini-percentage {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 1rem;
    font-weight: 700;
    color: var(--secondary);
}

.tasks-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
}

.tasks-column {
    background: var(--glass-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--glass-border);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    min-height: 400px;
}

.column-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--bg-tertiary);
    font-size: 1.1rem;
}

.task-count {
    background: var(--bg-tertiary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-full);
    font-size: 0.9rem;
    font-weight: 600;
    margin-left: auto;
}

.task-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

/* Task Card */
.task-card {
    background: var(--bg-secondary);
    border-left: 4px solid var(--priority-color, var(--primary));
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    cursor: pointer;
    position: relative;
}

.task-card:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-md);
}

.task-card.high-priority { --priority-color: var(--priority-high); }
.task-card.medium-priority { --priority-color: var(--priority-medium); }
.task-card.low-priority { --priority-color: var(--priority-low); }

.task-card.completed {
    opacity: 0.6;
    background: var(--bg-tertiary);
}

.task-card.completed .task-title {
    text-decoration: line-through;
}

.task-header {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-sm);
}

.task-checkbox {
    width: 24px;
    height: 24px;
    border: 2px solid var(--bg-tertiary);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
    transition: all var(--transition-fast);
}

.task-checkbox:hover {
    border-color: var(--primary);
}

.task-checkbox.checked {
    background: var(--success);
    border-color: var(--success);
    color: white;
}

.task-content {
    flex: 1;
}

.task-title {
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.task-description {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: var(--spacing-sm);
}

.task-meta {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    font-size: 0.75rem;
    color: var(--text-secondary);
}

.task-meta span {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.task-actions {
    position: absolute;
    top: var(--spacing-sm);
    right: var(--spacing-sm);
    display: flex;
    gap: var(--spacing-xs);
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.task-card:hover .task-actions {
    opacity: 1;
}

.task-action-btn {
    width: 28px;
    height: 28px;
    border: none;
    border-radius: var(--radius-sm);
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

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

.task-action-btn.delete:hover {
    background: var(--accent);
}

/* ===== SCHEDULE TAB ===== */
.schedule-controls {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.schedule-container {
    overflow-x: auto;
    padding: var(--spacing-lg);
}

.calendar-grid {
    min-width: 800px;
}

.week-row {
    display: grid;
    grid-template-columns: 80px repeat(7, 1fr);
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.week-header {
    display: contents;
}

.day-header {
    text-align: center;
    padding: var(--spacing-md);
    font-weight: 600;
    color: var(--primary);
}

.day-header.weekend {
    color: var(--accent);
}

.time-slot-label {
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.day-column {
    background: rgba(255, 255, 255, 0.3);
    border-radius: var(--radius-md);
    padding: var(--spacing-xs);
    min-height: 120px;
    transition: background var(--transition-fast);
}

.day-column:hover {
    background: rgba(46, 204, 113, 0.1);
}

.day-header.weekend + .day-column {
    background: rgba(231, 76, 60, 0.05);
}

.day-date {
    text-align: center;
    font-size: 0.8rem;
    margin-bottom: var(--spacing-xs);
    color: var(--text-secondary);
}

.day-sessions {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xs);
}

.session-block {
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    color: white;
    cursor: pointer;
    transition: all var(--transition-fast);
    font-weight: 500;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    background: var(--session-color, var(--primary));
    box-shadow: var(--shadow-sm);
}

.session-block:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-md);
}

.schedule-legend {
    display: flex;
    justify-content: center;
    gap: var(--spacing-xl);
    margin-top: var(--spacing-lg);
    flex-wrap: wrap;
}

.legend-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 0.9rem;
}

.legend-color {
    width: 24px;
    height: 12px;
    border-radius: var(--radius-sm);
}

.legend-color.high { background: var(--weight-high); }
.legend-color.medium { background: var(--weight-medium); }
.legend-color.low { background: var(--weight-low); }
.legend-color.personal { background: #667eea; }

/* ===== SHARE TAB ===== */
.share-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-lg);
}

.share-card {
    padding: var(--spacing-xl);
    text-align: center;
}

.share-card.full-width {
    grid-column: 1 / -1;
}

.share-icon {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: var(--spacing-md);
    animation: bounce 2s infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

.share-card h3 {
    margin-bottom: var(--spacing-md);
}

.share-card p {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
    font-size: 0.95rem;
}

.import-options {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

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

.file-btn {
    cursor: pointer;
}

.qr-output {
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    background: white;
    border-radius: var(--radius-md);
    display: inline-block;
}

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

.comparison-stats {
    display: grid;
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-xl);
}

.comparison-stat {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.comparison-bar {
    height: 24px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
    overflow: hidden;
    display: grid;
    grid-template-columns: 1fr 1fr;
}

.bar-fill {
    background: var(--primary);
    transition: width 0.5s ease;
}

.bar-fill.friend {
    background: #667eea;
}

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

/* ===== MODAL ===== */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(5px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: var(--spacing-md);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-normal);
}

.modal.active {
    opacity: 1;
    pointer-events: all;
}

.modal-content {
    max-width: 600px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    border-radius: var(--radius-xl);
    transform: scale(0.9);
    transition: transform var(--transition-normal);
}

.modal.active .modal-content {
    transform: scale(1);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 2px solid var(--bg-tertiary);
}

.modal-header h2 {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.3rem;
}

.close-btn {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.close-btn:hover {
    color: var(--accent);
}

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

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

.form-group label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 500;
    color: var(--text-primary);
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--bg-tertiary);
    border-radius: var(--radius-md);
    font-family: inherit;
    font-size: 1rem;
    transition: border-color var(--transition-fast);
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(46, 204, 113, 0.1);
}

.form-group textarea {
    resize: vertical;
    min-height: 80px;
}

/* ===== BUTTONS ===== */
.btn {
    padding: var(--spacing-md) var(--spacing-xl);
    border: none;
    border-radius: var(--radius-lg);
    font-family: inherit;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), var(--shadow-glow);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: var(--text-secondary);
    color: white;
}

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

.btn-danger:hover {
    background: var(--accent-dark);
    transform: scale(1.05);
}

.btn.full-width {
    width: 100%;
    justify-content: center;
}

/* ===== TOAST NOTIFICATIONS ===== */
.toast-container {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.toast {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-left: 4px solid var(--primary);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    min-width: 300px;
    animation: slideInRight 0.3s ease;
}

.toast.success { border-left-color: var(--success); }
.toast.error { border-left-color: var(--accent); }
.toast.warning { border-left-color: var(--warning); }

.toast i {
    font-size: 1.2rem;
}

.toast.success i { color: var(--success); }
.toast.error i { color: var(--accent); }
.toast.warning i { color: var(--warning); }

.toast-message {
    flex: 1;
    font-weight: 500;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    .app-container {
        padding: var(--spacing-sm);
    }

    .header {
        padding: var(--spacing-sm) var(--spacing-md);
        position: static;
    }

    .header-content {
        flex-direction: column;
        gap: var(--spacing-md);
    }

    .nav-tabs {
        order: 3;
        width: 100%;
        justify-content: center;
    }

    .tab-btn {
        padding: var(--spacing-xs) var(--spacing-md);
        font-size: 0.9rem;
    }

    .tab-btn span {
        display: none;
    }

    .tab-btn i {
        margin: 0;
    }

    .dashboard-grid {
        grid-template-columns: 1fr;
    }

    .tasks-container {
        grid-template-columns: 1fr;
    }

    .tasks-sticky-progress {
        position: static;
        justify-content: center;
    }

    .week-row {
        grid-template-columns: 60px repeat(7, 80px);
        font-size: 0.85rem;
    }

    .import-options {
        flex-direction: column;
    }
}

@media (max-width: 480px) {
    .logo h1 {
        font-size: 1.2rem;
    }

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

    .chapters-grid {
        grid-template-columns: 1fr;
    }

    .share-grid {
        grid-template-columns: 1fr;
    }
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
    background: var(--primary);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark);
}

/* ===== ANIMATIONS ===== */
.animate-on-scroll {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.animate-on-scroll.visible {
    opacity: 1;
    transform: translateY(0);
}