/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --gradient-1: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-2: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-3: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --gradient-4: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
    --gradient-5: linear-gradient(135deg, #30cfd0 0%, #330867 100%);
    --gradient-bg: linear-gradient(135deg, #0f0c29 0%, #302b63 50%, #24243e 100%);
    --gradient-bg-alt: linear-gradient(135deg, #1e3c72 0%, #2a5298 50%, #7e22ce 100%);
    
    --glass-bg: rgba(255, 255, 255, 0.08);
    --glass-bg-hover: rgba(255, 255, 255, 0.15);
    --glass-border: rgba(255, 255, 255, 0.18);
    --glass-border-hover: rgba(255, 255, 255, 0.3);
    --glass-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
    --glass-shadow-hover: 0 12px 40px 0 rgba(31, 38, 135, 0.5);
    --glow-shadow: 0 0 20px rgba(102, 126, 234, 0.3);
    
    --priority-low: #10b981;
    --priority-medium: #f59e0b;
    --priority-high: #ef4444;
    --priority-low-glow: rgba(16, 185, 129, 0.3);
    --priority-medium-glow: rgba(245, 158, 11, 0.3);
    --priority-high-glow: rgba(239, 68, 68, 0.3);
    
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.85);
    --text-muted: rgba(255, 255, 255, 0.6);
    --text-accent: #a78bfa;
    
    --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-bounce: all 0.5s cubic-bezier(0.68, -0.55, 0.265, 1.55);
    --transition-elastic: all 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--gradient-bg);
    min-height: 100vh;
    color: var(--text-primary);
    overflow-x: hidden;
    line-height: 1.6;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.3);
    border-radius: 10px;
    transition: var(--transition-smooth);
}

::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.5);
}

/* Loading Screen */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--gradient-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    opacity: 1;
    transition: opacity 0.5s ease;
}

.loading-screen.fade-out {
    opacity: 0;
    pointer-events: none;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top: 3px solid var(--text-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Landing Section */
.landing-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    transition: transform 0.8s ease, opacity 0.8s ease;
}

.landing-section.slide-up {
    transform: translateY(-100%);
    opacity: 0;
}

.landing-content {
    text-align: center;
    z-index: 2;
    padding: 2rem;
    max-width: 800px;
    animation: fadeInUp 1s ease;
}

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

.landing-headline {
    font-size: clamp(2.5rem, 5vw, 4rem);
    font-weight: 700;
    margin-bottom: 1.5rem;
    background: linear-gradient(45deg, #ffffff, #f0f0f0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: 0 0 30px rgba(255, 255, 255, 0.3);
}

.landing-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--text-secondary);
    margin-bottom: 2.5rem;
    font-weight: 400;
}

.cta-button {
    background: linear-gradient(135deg, var(--gradient-1), var(--gradient-2));
    border: 2px solid transparent;
    color: var(--text-primary);
    padding: 1.2rem 3.5rem;
    font-size: 1.2rem;
    font-weight: 700;
    border-radius: 60px;
    cursor: pointer;
    transition: var(--transition-elastic);
    backdrop-filter: blur(20px);
    box-shadow: 0 10px 40px rgba(102, 126, 234, 0.4), 0 0 60px rgba(102, 126, 234, 0.2);
    position: relative;
    overflow: hidden;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.cta-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.8s ease;
}

.cta-button::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(255, 255, 255, 0.15);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.8s, height 0.8s;
}

.cta-button:hover::before {
    left: 100%;
}

.cta-button:hover::after {
    width: 400px;
    height: 400px;
}

.cta-button:hover {
    transform: translateY(-5px) scale(1.05);
    box-shadow: 0 15px 50px rgba(102, 126, 234, 0.6), 0 0 80px rgba(102, 126, 234, 0.3);
    border-color: rgba(255, 255, 255, 0.4);
}

.cta-button:active {
    transform: translateY(-2px) scale(1.02);
    transition: all 0.1s ease;
}

/* Floating Elements */
.floating-elements {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    pointer-events: none;
}

.floating-element {
    position: absolute;
    background: linear-gradient(135deg, var(--gradient-2), var(--gradient-3));
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    backdrop-filter: blur(15px);
    box-shadow: 0 8px 32px rgba(31, 38, 135, 0.3), 0 0 40px rgba(102, 126, 234, 0.2);
}

.element-1 {
    width: 120px;
    height: 120px;
    top: 20%;
    left: 10%;
    animation: float 6s ease-in-out infinite;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.3), rgba(118, 75, 162, 0.3));
}

.element-2 {
    width: 80px;
    height: 80px;
    top: 60%;
    right: 15%;
    animation: float 8s ease-in-out infinite reverse;
    background: linear-gradient(135deg, rgba(240, 147, 251, 0.3), rgba(245, 87, 108, 0.3));
}

.element-3 {
    width: 100px;
    height: 100px;
    bottom: 20%;
    left: 20%;
    animation: float 7s ease-in-out infinite;
    background: linear-gradient(135deg, rgba(79, 172, 254, 0.3), rgba(0, 242, 254, 0.3));
}

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(180deg); }
}

/* App Section */
.app-section {
    min-height: 100vh;
    padding: 2rem;
    opacity: 0;
    transform: translateY(50px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

.app-section.active {
    opacity: 1;
    transform: translateY(0);
}

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

/* App Header */
.app-header {
    text-align: center;
    margin-bottom: 3rem;
    animation: fadeInDown 0.8s ease;
}

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

.app-title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 2rem;
    background: linear-gradient(45deg, #ffffff, #f0f0f0);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.progress-container {
    max-width: 400px;
    margin: 0 auto;
}

.progress-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.progress-text {
    color: var(--text-secondary);
}

.progress-count {
    color: var(--text-primary);
    font-weight: 600;
}

.progress-bar {
    width: 100%;
    height: 12px;
    background: var(--glass-bg);
    border: 2px solid var(--glass-border);
    border-radius: 15px;
    overflow: hidden;
    backdrop-filter: blur(20px);
    box-shadow: inset 0 2px 10px rgba(0, 0, 0, 0.1);
    position: relative;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--gradient-1), var(--gradient-3), var(--gradient-4));
    border-radius: 15px;
    transition: width 0.8s cubic-bezier(0.4, 0, 0.2, 1);
    width: 0%;
    position: relative;
    box-shadow: 0 0 20px rgba(102, 126, 234, 0.4);
}

.progress-fill::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    animation: shimmer 2s infinite;
}

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

/* Filter Tabs */
.filter-tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.filter-tab {
    background: var(--glass-bg);
    border: 2px solid var(--glass-border);
    color: var(--text-secondary);
    padding: 0.9rem 1.8rem;
    border-radius: 30px;
    cursor: pointer;
    transition: var(--transition-elastic);
    backdrop-filter: blur(15px);
    font-weight: 600;
    font-size: 0.95rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    position: relative;
    overflow: hidden;
}

.filter-tab::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left 0.6s ease;
}

.filter-tab:hover::before {
    left: 100%;
}

.filter-tab:hover {
    color: var(--text-primary);
    border-color: var(--glass-border-hover);
    background: var(--glass-bg-hover);
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.3);
}

.filter-tab.active {
    background: linear-gradient(135deg, var(--gradient-1), var(--gradient-3));
    color: var(--text-primary);
    border-color: transparent;
    box-shadow: 0 8px 30px rgba(102, 126, 234, 0.4), 0 0 40px rgba(102, 126, 234, 0.2);
    transform: translateY(-2px) scale(1.08);
}

/* Task Form */
.task-form-section {
    margin-bottom: 3rem;
}

.task-form {
    background: var(--glass-bg);
    border: 2px solid var(--glass-border);
    border-radius: 25px;
    padding: 2.5rem;
    backdrop-filter: blur(20px);
    box-shadow: var(--glass-shadow), 0 0 40px rgba(102, 126, 234, 0.1);
    position: relative;
    overflow: hidden;
}

.task-form::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr auto auto auto;
    gap: 1rem;
    align-items: end;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.task-input,
.priority-select,
.time-select {
    background: rgba(255, 255, 255, 0.08);
    border: 2px solid rgba(255, 255, 255, 0.15);
    color: var(--text-primary);
    padding: 1.2rem 1rem;
    border-radius: 15px;
    font-size: 1rem;
    transition: var(--transition-elastic);
    backdrop-filter: blur(10px);
    font-weight: 500;
}

.task-input::placeholder {
    color: var(--text-muted);
    font-weight: 400;
}

.task-input:focus,
.priority-select:focus,
.time-select:focus {
    outline: none;
    border-color: rgba(167, 139, 250, 0.5);
    background: rgba(255, 255, 255, 0.12);
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 8px 25px rgba(167, 139, 250, 0.2), 0 0 30px rgba(167, 139, 250, 0.1);
}

.priority-select option,
.time-select option {
    background: #2a5298;
    color: var(--text-primary);
}

.add-task-btn {
    background: linear-gradient(135deg, var(--gradient-1), var(--gradient-4));
    border: 2px solid transparent;
    color: var(--text-primary);
    padding: 1.2rem 2.5rem;
    border-radius: 18px;
    cursor: pointer;
    transition: var(--transition-elastic);
    font-weight: 700;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 0.8rem;
    white-space: nowrap;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    position: relative;
    overflow: hidden;
    box-shadow: 0 8px 30px rgba(102, 126, 234, 0.4), 0 0 40px rgba(102, 126, 234, 0.2);
}

.add-task-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.8s ease;
}

.add-task-btn:hover::before {
    left: 100%;
}

.add-task-btn:hover {
    transform: translateY(-4px) scale(1.05);
    box-shadow: 0 12px 40px rgba(102, 126, 234, 0.6), 0 0 60px rgba(102, 126, 234, 0.3);
    border-color: rgba(255, 255, 255, 0.3);
}

.add-task-btn:active {
    transform: translateY(-2px) scale(1.02);
    transition: all 0.1s ease;
}

.btn-icon {
    font-size: 1.2rem;
    font-weight: 700;
}

/* Tasks Section */
.tasks-section {
    min-height: 400px;
}

.tasks-container {
    display: grid;
    gap: 1.5rem;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
}

.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--text-muted);
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

/* Task Cards */
.task-card {
    background: var(--glass-bg);
    border: 2px solid var(--glass-border);
    border-radius: 20px;
    padding: 2rem;
    backdrop-filter: blur(20px);
    box-shadow: var(--glass-shadow), 0 0 30px rgba(102, 126, 234, 0.1);
    transition: var(--transition-elastic);
    animation: slideIn 0.5s ease;
    position: relative;
    overflow: hidden;
}

.task-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, rgba(167, 139, 250, 0.5), transparent);
    opacity: 0;
    transition: opacity 0.3s ease;
}

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

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

.task-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 15px 50px rgba(31, 38, 135, 0.6), 0 0 50px rgba(102, 126, 234, 0.2);
    border-color: var(--glass-border-hover);
    background: var(--glass-bg-hover);
}

.task-card.removing {
    animation: fadeOut 0.5s ease forwards;
}

@keyframes fadeOut {
    to {
        opacity: 0;
        transform: translateX(30px);
    }
}

.task-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.task-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    flex: 1;
    margin-right: 1rem;
    transition: var(--transition-smooth);
}

.task-card.completed .task-title {
    text-decoration: line-through;
    color: var(--text-muted);
}

.task-priority {
    padding: 0.4rem 1rem;
    border-radius: 25px;
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.8px;
    backdrop-filter: blur(10px);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: var(--transition-smooth);
}

.priority-low {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.3), rgba(16, 185, 129, 0.1));
    color: var(--priority-low);
    border: 2px solid rgba(16, 185, 129, 0.4);
    box-shadow: 0 4px 15px var(--priority-low-glow);
}

.priority-medium {
    background: linear-gradient(135deg, rgba(245, 158, 11, 0.3), rgba(245, 158, 11, 0.1));
    color: var(--priority-medium);
    border: 2px solid rgba(245, 158, 11, 0.4);
    box-shadow: 0 4px 15px var(--priority-medium-glow);
}

.priority-high {
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.3), rgba(239, 68, 68, 0.1));
    color: var(--priority-high);
    border: 2px solid rgba(239, 68, 68, 0.4);
    box-shadow: 0 4px 15px var(--priority-high-glow);
}

.task-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.task-time {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.task-time::before {
    content: '⏱';
    font-size: 1rem;
}

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

.task-btn {
    background: rgba(255, 255, 255, 0.08);
    border: 2px solid rgba(255, 255, 255, 0.15);
    color: var(--text-primary);
    padding: 0.8rem 1.2rem;
    border-radius: 12px;
    cursor: pointer;
    transition: var(--transition-elastic);
    font-size: 0.95rem;
    font-weight: 600;
    flex: 1;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    backdrop-filter: blur(10px);
    position: relative;
    overflow: hidden;
}

.task-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left 0.6s ease;
}

.task-btn:hover::before {
    left: 100%;
}

.task-btn:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-3px) scale(1.05);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.2);
}

.complete-btn {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.2), rgba(16, 185, 129, 0.1));
    border-color: rgba(16, 185, 129, 0.4);
    color: var(--priority-low);
    box-shadow: 0 4px 15px var(--priority-low-glow);
}

.complete-btn:hover {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.3), rgba(16, 185, 129, 0.2));
    box-shadow: 0 6px 25px var(--priority-low-glow);
}

.delete-btn {
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.2), rgba(239, 68, 68, 0.1));
    border-color: rgba(239, 68, 68, 0.4);
    color: var(--priority-high);
    box-shadow: 0 4px 15px var(--priority-high-glow);
}

.delete-btn:hover {
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.3), rgba(239, 68, 68, 0.2));
    box-shadow: 0 6px 25px var(--priority-high-glow);
}

.task-card.completed .complete-btn {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.15);
    color: var(--text-muted);
    box-shadow: none;
}

/* Responsive Design */
@media (max-width: 768px) {
    .app-section {
        padding: 1rem;
    }
    
    .app-title {
        font-size: 2rem;
    }
    
    .form-row {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .task-form {
        padding: 1.5rem;
    }
    
    .add-task-btn {
        width: 100%;
        justify-content: center;
    }
    
    .tasks-container {
        grid-template-columns: 1fr;
    }
    
    .filter-tabs {
        gap: 0.5rem;
    }
    
    .filter-tab {
        padding: 0.5rem 1rem;
        font-size: 0.9rem;
    }
    
    .landing-headline {
        font-size: 2rem;
    }
    
    .cta-button {
        padding: 0.75rem 2rem;
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .app-section {
        padding: 0.5rem;
    }
    
    .task-form {
        padding: 1rem;
    }
    
    .task-card {
        padding: 1rem;
    }
    
    .task-actions {
        flex-direction: column;
    }
    
    .filter-tabs {
        flex-direction: column;
        align-items: center;
    }
    
    .filter-tab {
        width: 100%;
        max-width: 200px;
        text-align: center;
    }
}