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

body {
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    overflow: hidden;
}

.container {
    max-width: 600px;
    width: 100%;
}

h1 {
    text-align: center;
    color: white;
    margin-bottom: 40px;
    font-size: 2.5em;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
    animation: slideDown 0.6s ease-out;
}

.checklist {
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    position: relative;
    display: flex;
    flex-direction: column;
}

.checklist-items {
    max-height: 60vh;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    margin-bottom: 20px;
    padding-right: 5px;
}

.checklist-items::-webkit-scrollbar {
    width: 8px;
}

.checklist-items::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 10px;
}

.checklist-items::-webkit-scrollbar-thumb {
    background: #667eea;
    border-radius: 10px;
}

.checklist-items::-webkit-scrollbar-thumb:hover {
    background: #764ba2;
}

.checklist-item {
    display: none;
    margin-bottom: 25px;
    padding: 20px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    border-radius: 12px;
    border-left: 5px solid #667eea;
    animation: slideIn 0.5s ease-out;
    transition: all 0.3s ease;
}

.checklist-item.active {
    display: flex;
    align-items: center;
    gap: 20px;
    scale: 1.05;
}

.checklist-item.completed {
    opacity: 0.6;
    border-left-color: #27ae60;
    background: linear-gradient(135deg, #e8f5e9 0%, #c8e6c9 100%);
}

.checkbox-wrapper {
    position: relative;
    flex-shrink: 0;
}

input[type="checkbox"] {
    width: 32px;
    height: 32px;
    cursor: pointer;
    accent-color: #667eea;
}

input[type="checkbox"]:checked {
    accent-color: #27ae60;
}

.item-text {
    flex-grow: 1;
    font-size: 1.1em;
    color: #333;
    font-weight: 500;
    transition: all 0.3s ease;
}

.checklist-item.completed .item-text {
    text-decoration: line-through;
    color: #999;
}

/* Celebration Effects */
.celebration {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 1000;
}

.confetti {
    position: absolute;
    width: 10px;
    height: 10px;
    background: #667eea;
    pointer-events: none;
    animation: confettiFall 3s ease-in forwards;
}

.confetti.red { background: #e74c3c; }
.confetti.gold { background: #f39c12; }
.confetti.green { background: #27ae60; }
.confetti.pink { background: #e91e63; }
.confetti.blue { background: #3498db; }

@keyframes confettiFall {
    to {
        transform: translateY(100vh) translateX(100px) rotate(360deg);
        opacity: 0;
    }
}

.sparkle {
    position: absolute;
    width: 5px;
    height: 5px;
    background: #ffd700;
    border-radius: 50%;
    animation: sparkleFloat 1.5s ease-out forwards;
}

@keyframes sparkleFloat {
    to {
        transform: translateY(-100px) translateX(50px);
        opacity: 0;
    }
}

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

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

.completion-message {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    padding: 40px;
    border-radius: 20px;
    text-align: center;
    font-size: 2em;
    font-weight: bold;
    color: #667eea;
    opacity: 0;
    pointer-events: none;
    z-index: 999;
    animation: popIn 0.6s ease-out forwards;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

@keyframes popIn {
    0% {
        opacity: 0;
        scale: 0;
    }
    50% {
        opacity: 1;
        scale: 1.1;
    }
    100% {
        opacity: 1;
        scale: 1;
    }
}

.progress {
    text-align: center;
    margin-top: 30px;
    color: #999;
    font-size: 0.9em;
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: #e0e0e0;
    border-radius: 3px;
    margin-top: 10px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
    width: 0%;
    transition: width 0.3s ease;
}

.congratulations {
    text-align: center;
    margin-top: 40px;
    padding: 30px;
    background: linear-gradient(135deg, #ffd89b 0%, #19547b 100%);
    border-radius: 12px;
    color: white;
    font-size: 1.3em;
    font-weight: bold;
    display: none;
    animation: slideUp 0.6s ease-out;
}

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

.welcome-screen {
    background: white;
    border-radius: 20px;
    padding: 60px 40px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    text-align: center;
    animation: slideDown 0.6s ease-out;
}

.welcome-screen p {
    font-size: 1.3em;
    color: #333;
    margin-bottom: 40px;
    line-height: 1.6;
}

.begin-button {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 16px 50px;
    font-size: 1.2em;
    font-weight: bold;
    border-radius: 50px;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
}

.begin-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.6);
}

.begin-button:active {
    transform: translateY(-1px);
}

.reset-button {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.4);
    padding: 8px 16px;
    font-size: 0.85em;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.reset-button:hover {
    background: rgba(255, 255, 255, 0.3);
    border-color: rgba(255, 255, 255, 0.6);
}

.reset-button:active {
    transform: scale(0.95);
}