/* --- RESET --- */
* { box-sizing: border-box; margin: 0; padding: 0; font-family: 'Noto Sans', sans-serif; }

body {
    background-color: #0f0f0f; /* Nền đen tối như hình */
    color: #e0e0e0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    position: relative;
}

/* --- NGÔN NGỮ (Góc phải) --- */
.lang-dropdown {
    position: absolute;
    top: 20px;
    right: 30px;
    background: #1e1e1e;
    padding: 8px 15px;
    border-radius: 4px;
    font-size: 13px;
    color: #888;
    cursor: pointer;
    border: 1px solid #333;
}

/* --- LOGO --- */
.login-wrapper {
    width: 100%;
    max-width: 400px;
    text-align: center;
    padding: 20px;
}

.login-logo {
    font-size: 32px;
    font-weight: 900;
    color: #3b4d6e; /* Màu xanh xám đậm của logo trong hình */
    margin-bottom: 25px;
    letter-spacing: 1px;
}

/* --- CARD --- */
.login-card {
    background-color: #1a1a1a; /* Nền card xám đen */
    border-radius: 8px;
    border: 1px solid #2a2a2a;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

/* --- TABS --- */
.login-tabs {
    display: flex;
    background-color: #151515;
    border-bottom: 1px solid #2a2a2a;
}
.tab-item {
    flex: 1;
    padding: 15px 0;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    color: #666;
    transition: 0.3s;
    text-decoration: none;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
}
.tab-item.active {
    color: #506891; /* Màu xanh active */
    background-color: #1a1a1a; /* Trùng màu nền card */
    border-top: 2px solid #506891;
}
.tab-item.inactive:hover {
    background-color: #1e1e1e;
    color: #aaa;
}

/* --- FORM BODY --- */
.login-body {
    padding: 30px 25px 40px; /* Padding rộng như hình */
}

.form-group {
    margin-bottom: 20px;
    text-align: left;
}
.form-group label {
    display: block;
    font-size: 12px;
    color: #666;
    margin-bottom: 8px;
    font-weight: 600;
}

.form-input {
    width: 100%;
    padding: 12px 15px;
    background-color: #121212; /* Input nền rất tối */
    border: 1px solid #333;
    border-radius: 4px;
    color: #fff;
    font-size: 14px;
    transition: 0.2s;
}
.form-input:focus {
    border-color: #506891;
    outline: none;
    background-color: #0f0f0f;
}

/* --- CHECKBOX --- */
.form-options {
    display: flex;
    align-items: center;
    margin-bottom: 25px;
}
.custom-checkbox {
    display: flex;
    align-items: center;
    cursor: pointer;
    font-size: 13px;
    color: #888;
    user-select: none;
}
.custom-checkbox input {
    display: none;
}
.checkmark {
    width: 18px;
    height: 18px;
    border: 2px solid #444;
    border-radius: 50%; /* Tròn như hình */
    margin-right: 8px;
    display: inline-block;
    position: relative;
}
.custom-checkbox input:checked ~ .checkmark {
    border-color: #506891;
    background-color: #506891;
}

/* --- BUTTON --- */
.btn-submit {
    width: 100%;
    padding: 12px;
    background-color: #4a6fa5; /* Màu xanh của nút trong hình */
    color: white;
    font-size: 15px;
    font-weight: bold;
    border-radius: 4px;
    transition: 0.3s;
}
.btn-submit:hover {
    background-color: #5a82b8;
    transform: translateY(-1px);
}

/* --- ERROR & FOOTER --- */
.alert-error {
    background: rgba(255, 77, 77, 0.1);
    color: #ff4d4d;
    padding: 10px;
    border-radius: 4px;
    margin-bottom: 20px;
    font-size: 13px;
    border: 1px solid #ff4d4d;
}

.footer-text {
    margin-top: 40px;
    font-size: 11px;
    color: #555;
}
.footer-text strong { color: #888; }