/* Ép màu nền đen sâu cho toàn bộ trang */
html, body {
    height: 100%;
    margin: 0;
    padding: 0;
    background-color: #020617 !important; /* Màu đen xanh của THT AI */
    color: #f8fafc;
}

body {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    overflow: hidden; /* Chống cuộn trang khi có hạt mạng lưới */
    position: relative;
}

#ai-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 0;
    background-color: #020617; /* Đảm bảo canvas cũng có nền đen */
}

.login-container {
    position: relative;
    z-index: 10;
}

#ai-canvas {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 0;
    pointer-events: none;
}

.login-container {
    width: 100%;
    max-width: 420px;
    z-index: 10;
    position: relative;
    padding: 20px;
}

.brand-badge {
    display: inline-block;
    background: rgba(56,189,248,0.1);
    color: var(--primary);
    font-weight: 800;
    font-size: 32px;
    font-style: italic;
    padding: 12px 28px;
    border-radius: 20px;
    border: 1px solid var(--primary);
    box-shadow: 0 0 20px rgba(56,189,248,0.4);
    margin-bottom: 15px;
}

.logo-section {
    text-align: center;
    margin-bottom: 35px;
}

    .logo-section h2 {
        color: #f8fafc;
        font-size: 24px;
        font-weight: 700;
    }

    .logo-section p {
        color: #94a3b8;
        font-size: 14px;
        margin-top: 5px;
    }

.login-card {
    background: rgba(15, 23, 42, 0.8);
    padding: 40px;
    border-radius: 32px;
    backdrop-filter: blur(20px);
    border: 1px solid rgba(56,189,248,0.2);
    box-shadow: 0 0 50px rgba(0,0,0,0.5);
}

.form-group {
    margin-bottom: 22px;
}

    .form-group label {
        display: block;
        font-size: 11px;
        font-weight: 700;
        color: var(--primary);
        text-transform: uppercase;
        letter-spacing: 1.5px;
        margin-bottom: 8px;
        margin-left: 5px;
    }

.input-wrapper {
    position: relative;
}

.icon-left {
    position: absolute;
    left: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: #64748b;
}

.toggle-password {
    position: absolute;
    right: 18px;
    top: 50%;
    transform: translateY(-50%);
    color: #64748b;
    cursor: pointer;
    transition: 0.3s;
}

    .toggle-password:hover {
        color: var(--primary);
    }

.input-wrapper input {
    width: 100%;
    padding: 16px 45px 16px 52px;
    background: rgba(2,6,23,0.9);
    border: 2px solid rgba(56,189,248,0.2);
    border-radius: 16px;
    color: #fff;
    font-size: 16px;
    outline: none;
    transition: 0.3s;
}

    .input-wrapper input:focus {
        border-color: var(--primary);
        box-shadow: 0 0 15px rgba(56,189,248,0.4);
        background: #000;
    }

.btn-login {
    width: 100%;
    padding: 18px;
    margin-top: 10px;
    background: linear-gradient(135deg, #0ea5e9, #38bdf8);
    border: none;
    border-radius: 16px;
    color: white;
    font-weight: 800;
    font-size: 15px;
    text-transform: uppercase;
    letter-spacing: 2px;
    cursor: pointer;
    transition: 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    box-shadow: 0 10px 20px rgba(56,189,248,0.3);
}

    .btn-login:hover {
        transform: translateY(-3px);
        box-shadow: 0 0 30px rgba(56,189,248,0.5);
    }

.footer {
    text-align: center;
    margin-top: 40px;
    font-size: 11px;
    color: #94a3b8;
    text-transform: uppercase;
    letter-spacing: 4px;
}

.error-alert {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #fca5a5;
    padding: 12px;
    border-radius: 12px;
    font-size: 13px;
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}