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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
    overflow: hidden;
    touch-action: pan-y;
}

.app-container {
    width: 100vw;
    height: 100vh;
    display: flex;
    flex-direction: column;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 16px 20px;
    background: linear-gradient(180deg, rgba(0,0,0,0.7) 0%, rgba(0,0,0,0) 100%);
}

.app-name {
    text-align: center;
    color: white;
    font-size: 20px;
    font-weight: 600;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.content-area {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 60px 20px 100px;
}

.html-container {
    width: 100%;
    max-width: 500px;
    aspect-ratio: 16 / 9;
    background: white;
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    overflow: hidden;
    position: relative;
}

.html-content {
    width: 100%;
    height: 100%;
    overflow-y: auto;
    overflow-x: hidden;
}

.demo-content {
    padding: 40px 30px;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.demo-content h2 {
    color: #2d3436;
    font-size: 28px;
    margin-bottom: 16px;
}

.demo-content p {
    color: #636e72;
    font-size: 16px;
    margin-bottom: 30px;
}

.demo-visual {
    width: 80px;
    height: 80px;
    position: relative;
}

.pulse-circle {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
        transform: scale(1);
    }
    50% {
        opacity: 0.5;
        transform: scale(1.1);
    }
}

.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 40px;
    padding: 20px 20px 30px;
    background: linear-gradient(180deg, rgba(0,0,0,0) 0%, rgba(0,0,0,0.7) 100%);
    z-index: 100;
}

.nav-btn {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
    -webkit-tap-highlight-color: transparent;
}

.nav-btn:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: scale(1.05);
}

.nav-btn:active {
    transform: scale(0.95);
}

.add-btn {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, #FF6B6B 0%, #FF8E53 100%);
    box-shadow: 0 8px 20px rgba(255, 107, 107, 0.4);
}

.add-btn:hover {
    background: linear-gradient(135deg, #FF8E53 0%, #FF6B6B 100%);
    transform: scale(1.1);
}

@media (max-width: 480px) {
    .html-container {
        max-width: calc(100vw - 40px);
    }
    
    .bottom-nav {
        gap: 30px;
    }
}

@media (min-height: 800px) {
    .content-area {
        padding: 80px 20px 120px;
    }
}

.slide-up-enter {
    animation: slideUpEnter 0.4s ease-out;
}

.slide-up-leave {
    animation: slideUpLeave 0.4s ease-out;
}

.slide-down-enter {
    animation: slideDownEnter 0.4s ease-out;
}

.slide-down-leave {
    animation: slideDownLeave 0.4s ease-out;
}

@keyframes slideUpEnter {
    from {
        transform: translateY(100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes slideUpLeave {
    from {
        transform: translateY(0);
        opacity: 1;
    }
    to {
        transform: translateY(-100%);
        opacity: 0;
    }
}

@keyframes slideDownEnter {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes slideDownLeave {
    from {
        transform: translateY(0);
        opacity: 1;
    }
    to {
        transform: translateY(100%);
        opacity: 0;
    }
}