/* ======================================================== */
/* 1. GIAO DIỆN CHỮ 3D VÀ NỀN TRÁI TIM (STYLE GỐC) */
/* ======================================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    overflow: hidden;
}

#text-container {
    position: absolute;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    align-items: center;
    padding: 10vh 0 15vh 0;
    z-index: 9999;
    opacity: 0;
    transition: 1.5s ease-in-out;
    pointer-events: none;
}

.show-text {
    opacity: 1 !important;
}

#text-container h1 {
    font-family: 'Arial Black', Impact, sans-serif;
    font-size: 80px;
    color: #ffffff;
    letter-spacing: 6px;
    text-transform: uppercase;
    text-shadow: 
        0px 1px 0px #ffb3d9, 0px 2px 0px #ff99cc, 0px 3px 0px #ff80bf,
        0px 4px 0px #ff66b3, 0px 5px 0px #ff4da6, 0px 6px 0px #ff3399,
        0px 7px 0px #ff1a8c, 0px 8px 10px rgba(0, 0, 0, 0.3),
        0px 15px 20px rgba(0, 0, 0, 0.2);
    animation: text-heartbeat 1.57s infinite linear;
}

#text-container h2 {
    font-family: 'Arial Black', Impact, sans-serif;
    font-size: 45px;
    color: #ff1493;
    letter-spacing: 4px;
    text-shadow: 
        0px 1px 0px #cc0066, 0px 2px 0px #b30059, 0px 3px 0px #99004d,
        0px 4px 0px #800040, 0px 5px 5px rgba(0, 0, 0, 0.4),
        0px 10px 15px rgba(0, 0, 0, 0.2);
    animation: text-heartbeat 1.57s infinite linear;
}

@keyframes text-heartbeat {
    0% { transform: scale(1); }
    15% { transform: scale(1.08); }
    30% { transform: scale(1); }
    45% { transform: scale(1.08); }
    100% { transform: scale(1); }
}

@media (max-width: 768px) {
    #text-container h1 { font-size: 50px; }
    #text-container h2 { font-size: 30px; }
}

/* ======================================================== */
/* 2. GIAO DIỆN MÀN HÌNH ĐĂNG NHẬP (LOGIN MỚI) */
/* ======================================================== */
#login-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: #ff99cc;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 100000;
    font-family: 'Arial', sans-serif;
    transition: opacity 0.8s ease-in-out;
}

.login-box {
    background-color: #ff2d95;
    padding: 45px 40px;
    border-radius: 20px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
    text-align: center;
    color: white;
    width: 25vw; 
    min-width: 320px;
}

@media (max-width: 768px) {
    .login-box {
        width: 66.66vw;
        min-width: unset;
        padding: 35px 25px;
    }
}

.login-box h3 {
    margin-bottom: 30px;
    font-size: 24px;
    letter-spacing: 1px;
    font-weight: bold;
    text-shadow: 0 2px 4px rgba(0,0,0,0.15);
}

.input-group {
    margin-bottom: 25px;
    text-align: left;
}

.input-group label {
    display: block;
    margin-bottom: 10px;
    font-size: 16px;
    font-weight: bold;
    letter-spacing: 0.5px;
}

.input-group input {
    width: 100%;
    padding: 16px 18px;
    border: none;
    border-radius: 10px;
    font-size: 18px;
    outline: none;
    color: #333;
    font-weight: 500;
    box-shadow: inset 0 2px 5px rgba(0,0,0,0.15);
}

.input-group input:focus {
    background-color: #fff;
    box-shadow: inset 0 2px 5px rgba(0,0,0,0.2), 0 0 0 3px rgba(255, 255, 255, 0.4);
}

.login-btn {
    width: 100%;
    padding: 16px;
    background-color: #ffffff;
    color: #ff2d95;
    border: none;
    border-radius: 10px;
    font-size: 18px;
    font-weight: bold;
    cursor: pointer;
    transition: transform 0.1s, background-color 0.2s;
    margin-top: 15px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.login-btn:active {
    transform: scale(0.97);
}

#login-error {
    color: #ffe600;
    font-size: 15px;
    margin-top: 20px;
    min-height: 22px;
    font-weight: bold;
    text-shadow: 0 1px 2px rgba(0,0,0,0.2);
}