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

body {
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(135deg, #ff9a9e 0%, #fad0c4 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.container {
    padding: 20px;
    width: 100%;
    max-width: 800px;
}

.birthday-card {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    padding: 40px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    position: relative;
    overflow: hidden;
}

.title {
    font-family: 'Dancing Script', cursive;
    font-size: 4em;
    color: #ff6b6b;
    margin-bottom: 20px;
    animation: fadeIn 2s ease-in;
}

.name {
    font-size: 2em;
    color: #4a4a4a;
    margin-bottom: 30px;
    animation: slideUp 1s ease-out;
}

.message {
    font-size: 1.2em;
    color: #666;
    line-height: 1.6;
    margin-bottom: 40px;
    animation: fadeIn 2s ease-in;
}

.btn {
    display: inline-block;
    padding: 15px 30px;
    background: #ff6b6b;
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    animation: pulse 2s infinite;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 15px rgba(255, 107, 107, 0.4);
}

.balloons {
    position: absolute;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    pointer-events: none;
}

.balloon {
    position: absolute;
    width: 30px;
    height: 40px;
    background: #ff6b6b;
    border-radius: 50%;
    animation: float 6s ease-in-out infinite;
}

.balloon:nth-child(1) {
    left: 10%;
    animation-delay: 0s;
}

.balloon:nth-child(2) {
    left: 50%;
    animation-delay: 2s;
    background: #ffd93d;
}

.balloon:nth-child(3) {
    left: 80%;
    animation-delay: 4s;
    background: #6b66ff;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0) rotate(0deg);
    }
    50% {
        transform: translateY(-20px) rotate(5deg);
    }
}

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

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

@keyframes pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
    100% {
        transform: scale(1);
    }
}

@media (max-width: 600px) {
    .birthday-card {
        padding: 20px;
    }
    
    .title {
        font-size: 3em;
    }
    
    .name {
        font-size: 1.5em;
    }
    
    .message {
        font-size: 1em;
    }
}