/* Reset and base styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    overflow-x: hidden;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* Black screen overlay */
.black-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: #000;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    transition: opacity 1s ease-out;
}

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

/* Action buttons */
.action-btn {
    position: relative;
    padding: 20px 40px;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #ffeaa7);
    background-size: 400% 400%;
    border: none;
    border-radius: 50px;
    cursor: pointer;
    font-size: 18px;
    font-weight: bold;
    color: white;
    text-transform: uppercase;
    letter-spacing: 2px;
    overflow: hidden;
    transition: all 0.3s ease;
    animation: gradientShift 3s ease infinite;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.action-btn:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.4);
}

.action-btn.lights-btn {
    margin-bottom: 50px;
}

.btn-text {
    position: relative;
    z-index: 2;
}

.btn-glow {
    position: absolute;
    top: -2px;
    left: -2px;
    right: -2px;
    bottom: -2px;
    border-radius: 50px;
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #ffeaa7);
    background-size: 400% 400%;
    animation: gradientShift 3s ease infinite;
    filter: blur(10px);
    opacity: 0.7;
    z-index: -1;
}

@keyframes gradientShift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

/* Main content */
.main-content {
    opacity: 0;
    transition: opacity 1s ease-in;
    min-height: 100vh;
    position: relative;
}

.main-content.visible {
    opacity: 1;
}

/* Header */
.header {
    text-align: center;
    padding: 20px;
    position: relative;
    z-index: 10;
}

.lights-container {
    display: flex;
    justify-content: space-around;
    align-items: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
    gap: 10px;
}

.light-container {
    display: inline-block;
    position: relative;
    animation: lightTwinkle 2s ease-in-out infinite alternate;
    margin: 5px;
}

.light-bulb {
    width: 40px;
    height: 60px;
    object-fit: contain;
    filter: drop-shadow(0 0 10px rgba(255, 255, 255, 0.5));
}

.light-container::before {
    content: '';
    position: absolute;
    top: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 20px;
    background: #333;
}

@keyframes lightTwinkle {
    0% { opacity: 0.6; transform: scale(1); }
    100% { opacity: 1; transform: scale(1.1); }
}

.birthday-title {
    font-size: clamp(2rem, 5vw, 4rem);
    color: #fff;
    text-shadow: 0 0 20px rgba(255, 255, 255, 0.8);
    margin: 20px 0;
    animation: titleGlow 3s ease-in-out infinite alternate;
}

@keyframes titleGlow {
    0% { text-shadow: 0 0 20px rgba(255, 255, 255, 0.8); }
    100% { text-shadow: 0 0 40px rgba(255, 255, 255, 1), 0 0 60px rgba(255, 255, 255, 0.8); }
}

/* Action buttons container */
.action-buttons {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin: 40px 0;
    flex-wrap: wrap;
}

.hidden {
    display: none !important;
}

/* Balloons */
.balloons-container {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    pointer-events: none;
    z-index: 5;
}

.balloon {
    position: absolute;
    animation: floatUp 4s ease-out forwards;
}

.balloon-image {
    width: 60px;
    height: 80px;
    object-fit: contain;
    filter: drop-shadow(2px 2px 4px rgba(0, 0, 0, 0.3));
}

@keyframes floatUp {
    0% {
        transform: translateY(100vh) rotate(0deg);
        opacity: 0;
    }
    10% {
        opacity: 1;
    }
    100% {
        transform: translateY(-20vh) rotate(360deg);
        opacity: 1;
    }
}

/* Cake */
.cake-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    margin: 40px 0;
    animation: cakeEntrance 1s ease-out;
}

@keyframes cakeEntrance {
    0% {
        transform: scale(0) rotate(180deg);
        opacity: 0;
    }
    100% {
        transform: scale(1) rotate(0deg);
        opacity: 1;
    }
}

.cake-image {
    width: 128px;
    height: 128px;
    object-fit: contain;
    animation: cakeBounce 2s ease-in-out infinite;
    margin-bottom: 20px;
    filter: drop-shadow(4px 4px 8px rgba(0, 0, 0, 0.3));
}

@keyframes cakeBounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

.candles {
    display: flex;
    gap: 10px;
}

.candle {
    font-size: 2rem;
    animation: candleFlicker 1s ease-in-out infinite alternate;
}

@keyframes candleFlicker {
    0% { opacity: 0.8; transform: scale(1); }
    100% { opacity: 1; transform: scale(1.1); }
}

/* Images */
.images-container {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin: 40px 20px;
    flex-wrap: wrap;
    animation: imagesReveal 2s ease-out;
}

@keyframes imagesReveal {
    0% {
        opacity: 0;
        transform: translateY(50px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
    }
}

.image-frame {
    background: linear-gradient(45deg, #ff6b6b, #4ecdc4);
    padding: 10px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    transform: rotate(-2deg);
    transition: transform 0.3s ease;
}

.image-frame:nth-child(even) {
    transform: rotate(2deg);
}

.image-frame:hover {
    transform: rotate(0deg) scale(1.05);
}

.birthday-image {
    width: 250px;
    height: 250px;
    object-fit: cover;
    border-radius: 15px;
    display: block;
}

/* Confetti */
.confetti-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 15;
}

.confetti {
    position: absolute;
    width: 10px;
    height: 10px;
    background: #ff6b6b;
    animation: confettiFall 3s linear infinite;
}

.confetti:nth-child(2n) { background: #4ecdc4; }
.confetti:nth-child(3n) { background: #45b7d1; }
.confetti:nth-child(4n) { background: #96ceb4; }
.confetti:nth-child(5n) { background: #ffeaa7; }

@keyframes confettiFall {
    0% {
        transform: translateY(-100vh) rotate(0deg);
        opacity: 1;
    }
    100% {
        transform: translateY(100vh) rotate(720deg);
        opacity: 0;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .action-btn {
        padding: 15px 30px;
        font-size: 16px;
        margin: 10px;
    }
    
    .lights-container {
        justify-content: center;
    }
    
    .light-bulb {
        width: 30px;
        height: 45px;
    }
    
    .light-container {
        margin: 3px;
    }
    
    .birthday-title {
        font-size: 2.5rem;
        margin: 15px 0;
    }
    
    .action-buttons {
        flex-direction: column;
        align-items: center;
        gap: 20px;
    }
    
    .cake-image {
        width: 96px;
        height: 96px;
    }
    
    .birthday-image {
        width: 200px;
        height: 200px;
    }
    
    .images-container {
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 480px) {
    .action-btn {
        padding: 12px 25px;
        font-size: 14px;
    }
    
    .birthday-title {
        font-size: 2rem;
    }
    
    .cake-image {
        width: 80px;
        height: 80px;
    }
    
    .birthday-image {
        width: 150px;
        height: 150px;
    }
    
    .light-bulb {
        width: 25px;
        height: 35px;
    }
}