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

body{
    background: center center no-repeat;
    background-size: cover;
    width: 100vw;
    height: 100vh;  
    align-items: center;
    justify-items: center;
}

.container{ 
    width: 90%; 
    margin-top: 50px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center; 
    border-radius: 30px;
    box-shadow: 6px 6px 12px rgba(0,0,0,0.15),
                -6px -6px 12px rgba(255,255,255,0.7);
}

.container input{
    width: 80%;
    height: 40px;
    margin: 10px; 
    box-shadow: 6px 6px 12px rgba(0,0,0,0.15),
                -6px -6px 12px rgba(255,255,255,0.7);
    padding: 12px 28px;
    border-radius: 999px;
    border: 1px solid rgba(255, 255, 255, 0.45); /* viền kính mỏng */
    
    color: rgba(0, 0, 0, 0.85);
    font-size: 16px;
    font-weight: 500;
    letter-spacing: -0.2px; /*tracking âm nhẹ */
    cursor: pointer;

    /* Liquid glass effect */
    background: rgba(255, 255, 255, 0.35);
    backdrop-filter: blur(20px) saturate(1.8);
    -webkit-backdrop-filter: blur(20px) saturate(1.8);

    box-shadow:
        0 2px 8px rgba(0, 0, 0, 0.12),          /* shadow ngoài nhẹ */
        inset 0 1px 0 rgba(255, 255, 255, 0.7),  /* specular highlight trên */
        inset 0 -1px 0 rgba(0, 0, 0, 0.08);      /* bóng tối dưới */

    transition: all 0.2s cubic-bezier(0.25, 0.46, 0.45, 0.94); /* iOS spring */
}

.container input:hover {
    background: rgba(255, 255, 255, 0.5);
    box-shadow:
        0 4px 16px rgba(0, 0, 0, 0.15),
        inset 0 1px 0 rgba(255, 255, 255, 0.8),
        inset 0 -1px 0 rgba(0, 0, 0, 0.06); 
}

.container input:active {
    transform: scale(0.97); /* nhẹ hơn */
    background: rgba(255, 255, 255, 0.25);
    box-shadow:
        0 1px 4px rgba(0, 0, 0, 0.1),
        inset 0 1px 0 rgba(255, 255, 255, 0.5),
        inset 0 2px 6px rgba(0, 0, 0, 0.08); /* pressed effect */
    transition-duration: 0.08s;
}

.container input:focus {
    outline: none;
    box-shadow:
        0 4px 16px rgba(0, 0, 0, 0.2),
        inset 0 1px 0 rgba(255, 255, 255, 0.9),
        inset 0 -1px 0 rgba(0, 0, 0, 0.1);
}

.ios-btn {
    margin: 10px 0;
    padding: 12px 28px;
    border-radius: 999px;
    border: 1px solid rgba(255, 255, 255, 0.45); /* viền kính mỏng */
    
    color: rgba(0, 0, 0, 0.85);
    font-size: 16px;
    font-weight: 500;
    letter-spacing: -0.2px; /*tracking âm nhẹ */
    cursor: pointer;

    /* Liquid glass effect */
    background: rgba(255, 255, 255, 0.35);
    backdrop-filter: blur(20px) saturate(1.8);
    -webkit-backdrop-filter: blur(20px) saturate(1.8);

    box-shadow:
        0 2px 8px rgba(0, 0, 0, 0.12),          /* shadow ngoài nhẹ */
        inset 0 1px 0 rgba(255, 255, 255, 0.7),  /* specular highlight trên */
        inset 0 -1px 0 rgba(0, 0, 0, 0.08);      /* bóng tối dưới */

    transition: all 0.2s cubic-bezier(0.25, 0.46, 0.45, 0.94); /* iOS spring */
}

.ios-btn:hover {
    background: rgba(255, 255, 255, 0.5);
    box-shadow:
        0 4px 16px rgba(0, 0, 0, 0.15),
        inset 0 1px 0 rgba(255, 255, 255, 0.8),
        inset 0 -1px 0 rgba(0, 0, 0, 0.06); 
}

.ios-btn:active {
    transform: scale(0.97); /* nhẹ hơn */
    background: rgba(255, 255, 255, 0.25);
    box-shadow:
        0 1px 4px rgba(0, 0, 0, 0.1),
        inset 0 1px 0 rgba(255, 255, 255, 0.5),
        inset 0 2px 6px rgba(0, 0, 0, 0.08); /* pressed effect */
    transition-duration: 0.08s;
}
  
.container p{
    margin: 20px;
    font-size: 18px;
    color: #333;
}