:root {
    /* Cosmic Color Palette */
    --color-space-deep: #0a0118;
    --color-space-mid: #150828;
    --color-space-light: #1f0f3d;
    
    --color-nebula-purple: #667eea;
    --color-nebula-pink: #764ba2;
    --color-nebula-blue: #4158D0;
    --color-cosmic-teal: #43e9c1;
    --color-stardust: #ffd89b;
    
    --color-glass-bg: rgba(255, 255, 255, 0.05);
    --color-glass-border: rgba(255, 255, 255, 0.1);
    --color-glass-hover: rgba(255, 255, 255, 0.08);
    
    --color-text-primary: #ffffff;
    --color-text-secondary: rgba(255, 255, 255, 0.7);
    --color-text-tertiary: rgba(255, 255, 255, 0.4);
    
    --color-priority-high: #ff6b9d;
    --color-priority-medium: #ffa94d;
    --color-priority-low: #43e9c1;
    
    --color-success: #43e9c1;
    --color-danger: #ff6b9d;
    
    --gradient-cosmic: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-sunset: linear-gradient(135deg, #ffa94d 0%, #ff6b9d 100%);
    --gradient-ocean: linear-gradient(135deg, #4158D0 0%, #43e9c1 100%);
    --gradient-star: linear-gradient(135deg, #ffd89b 0%, #ffa94d 100%);
    
    --font-display: 'Syne', sans-serif;
    --font-body: 'Crimson Pro', serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    --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: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    
    --blur-sm: 20px;
    --blur-md: 40px;
    --blur-lg: 60px;
    
    --transition-fast: 200ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 350ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    font-family: var(--font-body);
    background: var(--color-space-deep);
    color: var(--color-text-primary);
    line-height: 1.7;
    overflow-x: hidden;
    position: relative;
}

/* Cosmic Background */
.cosmic-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 0;
    overflow: hidden;
    pointer-events: none;
}

.orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.4;
    animation: float-orb 20s ease-in-out infinite;
}

.orb-1 {
    width: 600px;
    height: 600px;
    background: radial-gradient(circle, var(--color-nebula-purple), transparent);
    top: -10%;
    right: -10%;
    animation-delay: 0s;
}

.orb-2 {
    width: 500px;
    height: 500px;
    background: radial-gradient(circle, var(--color-nebula-pink), transparent);
    bottom: -10%;
    left: -5%;
    animation-delay: 3s;
}

.orb-3 {
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, var(--color-cosmic-teal), transparent);
    top: 40%;
    left: 50%;
    animation-delay: 6s;
}

@keyframes float-orb {
    0%, 100% { transform: translate(0, 0) scale(1); }
    33% { transform: translate(50px, -50px) scale(1.1); }
    66% { transform: translate(-30px, 30px) scale(0.9); }
}

.stars {
    position: absolute;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(2px 2px at 20px 30px, rgba(255, 255, 255, 0.3), transparent),
        radial-gradient(2px 2px at 60px 70px, rgba(255, 255, 255, 0.2), transparent),
        radial-gradient(1px 1px at 50px 50px, rgba(255, 255, 255, 0.4), transparent),
        radial-gradient(1px 1px at 130px 80px, rgba(255, 255, 255, 0.3), transparent),
        radial-gradient(2px 2px at 90px 10px, rgba(255, 255, 255, 0.25), transparent);
    background-size: 200px 200px;
    animation: twinkle 3s ease-in-out infinite;
}

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

/* Glassmorphic Container */
.glass {
    background: var(--color-glass-bg);
    backdrop-filter: blur(var(--blur-sm));
    -webkit-backdrop-filter: blur(var(--blur-sm));
    border: 1px solid var(--color-glass-border);
    box-shadow: 
        0 8px 32px 0 rgba(0, 0, 0, 0.37),
        inset 0 1px 0 0 rgba(255, 255, 255, 0.1);
}

/* App Container */
.app-container {
    display: grid;
    grid-template-columns: 340px 1fr;
    height: 100vh;
    position: relative;
    z-index: 1;
    padding: var(--spacing-lg);
    gap: var(--spacing-lg);
}

/* Sidebar */
.sidebar {
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    overflow-y: auto;
    position: relative;
    animation: slideInLeft 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes slideInLeft {
    from {
        opacity: 0;
        transform: translateX(-30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.sidebar-header {
    margin-bottom: var(--spacing-2xl);
    padding-bottom: var(--spacing-xl);
    border-bottom: 2px solid var(--color-glass-border);
}

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

.logo-icon {
    animation: pulse-glow 3s ease-in-out infinite;
}

@keyframes pulse-glow {
    0%, 100% { 
        filter: drop-shadow(0 0 8px rgba(102, 126, 234, 0.6));
    }
    50% { 
        filter: drop-shadow(0 0 16px rgba(102, 126, 234, 0.9));
    }
}

.app-title {
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    background: var(--gradient-cosmic);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-xs);
}

.app-subtitle {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

/* Section Header */
.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
}

.section-header h2 {
    font-family: var(--font-display);
    font-size: 0.875rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.15em;
    color: var(--color-text-secondary);
}

/* Projects List */
.projects-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.project-item {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-base);
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: relative;
    overflow: hidden;
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid transparent;
}

.project-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 3px;
    background: var(--gradient-cosmic);
    transform: scaleY(0);
    transition: transform var(--transition-base);
}

.project-item:hover {
    background: var(--color-glass-hover);
    border-color: var(--color-glass-border);
    transform: translateX(4px);
}

.project-item:hover::before {
    transform: scaleY(1);
}

.project-item.active {
    background: var(--color-glass-hover);
    border-color: var(--color-nebula-purple);
    box-shadow: 0 0 20px rgba(102, 126, 234, 0.2);
}

.project-item.active::before {
    transform: scaleY(1);
}

.project-name {
    font-weight: 600;
    color: var(--color-text-primary);
    font-size: 0.95rem;
}

.project-count {
    font-family: var(--font-mono);
    font-size: 0.75rem;
    color: var(--color-text-tertiary);
    background: rgba(255, 255, 255, 0.05);
    padding: 0.25rem 0.625rem;
    border-radius: var(--radius-sm);
    min-width: 2rem;
    text-align: center;
}

.delete-project {
    opacity: 0;
    padding: 0.25rem;
    background: none;
    border: none;
    color: var(--color-text-tertiary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.project-item:hover .delete-project {
    opacity: 1;
}

.delete-project:hover {
    color: var(--color-danger);
    transform: scale(1.1);
}

/* Main Content */
.main-content {
    border-radius: var(--radius-xl);
    overflow-y: auto;
    position: relative;
    animation: slideInRight 0.6s cubic-bezier(0.16, 1, 0.3, 1);
    padding: var(--spacing-xl);
}

@keyframes slideInRight {
    from {
        opacity: 0;
        transform: translateX(30px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.content-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: var(--spacing-2xl);
    padding-bottom: var(--spacing-xl);
    border-bottom: 1px solid var(--color-glass-border);
}

.header-content {
    flex: 1;
}

.project-title {
    font-family: var(--font-display);
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    margin-bottom: var(--spacing-xs);
    background: var(--gradient-cosmic);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.1;
}

.project-meta {
    font-family: var(--font-mono);
    font-size: 0.875rem;
    color: var(--color-text-tertiary);
    letter-spacing: 0.05em;
}

/* Buttons */
.btn-primary {
    background: var(--gradient-cosmic);
    color: white;
    border: none;
    padding: 0.875rem 2rem;
    border-radius: var(--radius-md);
    font-weight: 700;
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    transition: all var(--transition-base);
    font-family: var(--font-display);
    font-size: 0.875rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    position: relative;
    overflow: hidden;
}

.gradient-btn {
    box-shadow: 0 8px 24px rgba(102, 126, 234, 0.4);
}

.gradient-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 32px rgba(102, 126, 234, 0.6);
}

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

.btn-shine {
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.5s;
}

.gradient-btn:hover .btn-shine {
    left: 100%;
}

.btn-icon-inline {
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-secondary {
    background: transparent;
    color: var(--color-text-primary);
    border: 1px solid var(--color-glass-border);
    padding: 0.875rem 2rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    font-family: var(--font-display);
    font-size: 0.875rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.btn-secondary:hover {
    background: var(--color-glass-hover);
    border-color: var(--color-nebula-purple);
}

.btn-danger {
    background: transparent;
    color: var(--color-danger);
    border: 1px solid var(--color-danger);
    padding: 0.875rem 2rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-base);
    font-family: var(--font-display);
    font-size: 0.875rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.btn-danger:hover {
    background: var(--color-danger);
    color: white;
    box-shadow: 0 8px 24px rgba(255, 107, 157, 0.4);
}

.btn-icon {
    background: transparent;
    border: none;
    color: var(--color-text-secondary);
    cursor: pointer;
    padding: var(--spacing-sm);
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-icon:hover {
    background: var(--color-glass-hover);
    color: var(--color-text-primary);
    transform: scale(1.1);
}

.btn-icon.glow:hover {
    box-shadow: 0 0 16px rgba(102, 126, 234, 0.5);
}

/* Todos Container */
.todos-container {
    display: grid;
    gap: var(--spacing-md);
}

.todo-item {
    background: var(--color-glass-bg);
    backdrop-filter: blur(var(--blur-sm));
    border: 1px solid var(--color-glass-border);
    border-radius: var(--radius-lg);
    padding: var(--spacing-xl);
    transition: all var(--transition-base);
    cursor: pointer;
    position: relative;
    overflow: hidden;
    animation: fadeSlideIn 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

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

.todo-item::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: var(--priority-gradient);
    opacity: 0;
    transition: opacity var(--transition-base);
}

.todo-item:hover {
    border-color: var(--color-glass-border);
    transform: translateY(-4px) scale(1.01);
    box-shadow: 0 16px 48px rgba(0, 0, 0, 0.5);
    background: var(--color-glass-hover);
}

.todo-item:hover::before {
    opacity: 1;
}

.todo-item.completed {
    opacity: 0.5;
}

.todo-item.completed .todo-title {
    text-decoration: line-through;
    color: var(--color-text-tertiary);
}

.todo-header {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-lg);
}

.todo-checkbox {
    width: 24px;
    height: 24px;
    border: 2px solid var(--color-glass-border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    flex-shrink: 0;
    margin-top: 0.125rem;
    position: relative;
    background: rgba(255, 255, 255, 0.02);
}

.todo-checkbox:hover {
    border-color: var(--color-nebula-purple);
    box-shadow: 0 0 12px rgba(102, 126, 234, 0.4);
}

.todo-checkbox.checked {
    background: var(--gradient-cosmic);
    border-color: var(--color-nebula-purple);
    box-shadow: 0 0 16px rgba(102, 126, 234, 0.6);
}

.todo-checkbox.checked::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: 0.875rem;
    font-weight: bold;
}

.todo-content {
    flex: 1;
}

.todo-title {
    font-family: var(--font-display);
    font-size: 1.375rem;
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: var(--spacing-sm);
    letter-spacing: -0.01em;
}

.todo-description {
    font-size: 0.9375rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--spacing-md);
}

.todo-meta {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

.todo-tag {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: 0.375rem 0.875rem;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 600;
    font-family: var(--font-mono);
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.priority-tag {
    background: var(--tag-bg);
    color: var(--tag-color);
    border: 1px solid var(--tag-border);
    box-shadow: 0 0 12px var(--tag-glow);
}

.priority-high {
    --tag-bg: rgba(255, 107, 157, 0.15);
    --tag-color: var(--color-priority-high);
    --tag-border: rgba(255, 107, 157, 0.3);
    --tag-glow: rgba(255, 107, 157, 0.2);
    --priority-gradient: var(--gradient-sunset);
}

.priority-medium {
    --tag-bg: rgba(255, 169, 77, 0.15);
    --tag-color: var(--color-priority-medium);
    --tag-border: rgba(255, 169, 77, 0.3);
    --tag-glow: rgba(255, 169, 77, 0.2);
    --priority-gradient: var(--gradient-star);
}

.priority-low {
    --tag-bg: rgba(67, 233, 193, 0.15);
    --tag-color: var(--color-priority-low);
    --tag-border: rgba(67, 233, 193, 0.3);
    --tag-glow: rgba(67, 233, 193, 0.2);
    --priority-gradient: var(--gradient-ocean);
}

.date-tag {
    background: rgba(255, 255, 255, 0.05);
    color: var(--color-text-secondary);
    border: 1px solid var(--color-glass-border);
}

.date-tag.overdue {
    background: rgba(255, 107, 157, 0.15);
    color: var(--color-danger);
    border: 1px solid rgba(255, 107, 157, 0.3);
    box-shadow: 0 0 12px rgba(255, 107, 157, 0.2);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: var(--spacing-3xl);
    color: var(--color-text-tertiary);
}

.empty-state svg {
    width: 100px;
    height: 100px;
    margin-bottom: var(--spacing-xl);
    opacity: 0.2;
    stroke: var(--color-nebula-purple);
    animation: float-gentle 3s ease-in-out infinite;
}

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

.empty-state h3 {
    font-family: var(--font-display);
    font-size: 1.5rem;
    margin-bottom: var(--spacing-sm);
    color: var(--color-text-secondary);
}

.empty-state p {
    font-size: 0.9375rem;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 1000;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
}

.modal.active {
    display: flex;
}

.modal-backdrop {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(8px);
    animation: fadeIn var(--transition-base);
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.modal-content {
    position: relative;
    border-radius: var(--radius-xl);
    max-width: 600px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    z-index: 1;
    animation: modalSlideUp var(--transition-slow) cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes modalSlideUp {
    from {
        opacity: 0;
        transform: translateY(40px) scale(0.95);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.modal-small {
    max-width: 450px;
}

.modal-header {
    padding: var(--spacing-xl);
    border-bottom: 1px solid var(--color-glass-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h3 {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 800;
    background: var(--gradient-cosmic);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* Forms */
form {
    padding: var(--spacing-xl);
}

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

.form-group label {
    display: block;
    font-family: var(--font-display);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--color-glass-border);
    border-radius: var(--radius-md);
    padding: 0.875rem 1rem;
    color: var(--color-text-primary);
    font-family: var(--font-body);
    font-size: 0.9375rem;
    transition: all var(--transition-base);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--color-nebula-purple);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.2);
    background: rgba(255, 255, 255, 0.05);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
    color: var(--color-text-tertiary);
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-md);
}

.modal-actions {
    padding: var(--spacing-xl);
    border-top: 1px solid var(--color-glass-border);
    display: flex;
    gap: var(--spacing-md);
    justify-content: flex-end;
}

/* Detail View */
.detail-content {
    padding: var(--spacing-xl);
}

.detail-field {
    margin-bottom: var(--spacing-xl);
}

.detail-label {
    font-family: var(--font-display);
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: var(--spacing-sm);
}

.detail-value {
    color: var(--color-text-primary);
    font-size: 0.9375rem;
    line-height: 1.6;
}

.detail-value.large {
    font-size: 1.375rem;
    font-weight: 600;
}

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

::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.02);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb {
    background: var(--gradient-cosmic);
    border-radius: var(--radius-sm);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gradient-sunset);
}

/* Responsive */
@media (max-width: 1024px) {
    .app-container {
        grid-template-columns: 1fr;
        padding: var(--spacing-md);
    }
    
    .sidebar {
        display: none;
    }
    
    .project-title {
        font-size: 2.5rem;
    }
}

@media (max-width: 768px) {
    .form-row {
        grid-template-columns: 1fr;
    }
    
    .content-header {
        flex-direction: column;
        gap: var(--spacing-md);
    }
    
    .project-title {
        font-size: 2rem;
    }
}

/* Special Effects */
@keyframes shimmer {
    0% { background-position: -1000px 0; }
    100% { background-position: 1000px 0; }
}

.shimmer {
    background: linear-gradient(
        90deg,
        transparent 0%,
        rgba(255, 255, 255, 0.1) 50%,
        transparent 100%
    );
    background-size: 1000px 100%;
    animation: shimmer 3s infinite;
}