/* รีเซ็ตค่าเริ่มต้น */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: "Poppins", sans-serif;
}

/* พื้นหลังแบบ Gradient เข้มขึ้น */
body {
    background: linear-gradient(135deg, #0f1a40, #162d6b);
    background-size: cover;
    background-attachment: fixed;
    color: white;
    display: flex;
    flex-direction: column;
    align-items: center;
    height: 100vh;
}

/* แถบด้านบน (Login Button) */
.top-bar {
    width: 100%;
    padding: 15px;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(10px);
    display: flex;
    justify-content: flex-end;
    align-items: center;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 10;
}

.top-bar .btn-login {
    padding: 12px 18px;
    font-size: 16px;
    font-weight: bold;
    color: white;
    background: #004aad;
    border: none;
    border-radius: 10px;
    transition: 0.3s ease-in-out;
    cursor: pointer;
    margin-right: 20px;
}

.top-bar .btn-login:hover {
    background: #003580;
    transform: scale(1.05);
}

/* ส่วนหัวของฟอร์ม */
.header {
    width: 40%;
    margin-top: 90px;
    color: white;
    background: #004aad;
    text-align: center;
    padding: 20px;
    font-size: 22px;
    font-weight: bold;
    border-radius: 20px 20px 0px 0px;
}

/* กล่องฟอร์ม */
form, .content {
    width: 40%;
    padding: 30px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    backdrop-filter: blur(15px);
    box-shadow: 5px 5px 20px rgba(0, 0, 0, 0.5);
    transition: 0.3s ease-in-out;
}

/* กล่องอินพุต */
.input-group {
    margin: 15px 0;
}

.input-group label {
    display: block;
    font-size: 17px;
    font-weight: bold;
    color: white;
    margin-bottom: 5px;
}

.input-group input {
    width: 100%;
    padding: 12px;
    font-size: 16px;
    border: 2px solid #004aad;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.2);
    outline: none;
    color: white;
    transition: 0.3s;
}

.input-group input::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.input-group input:focus {
    border-color: #0056d2;
    box-shadow: 0px 0px 10px rgba(0, 102, 255, 0.5);
}

/* ปุ่ม */
.btn {
    display: block;
    width: 100%;
    padding: 15px;
    font-size: 18px;
    font-weight: bold;
    color: white;
    background: #0056d2;
    border: none;
    border-radius: 12px;
    transition: 0.3s ease-in-out;
    cursor: pointer;
    text-align: center;
}

.btn:hover {
    background: #004aad;
    transform: scale(1.05);
}
/* ลิงก์ Sign Up */
.sign-link {
    margin-top: 15px;
    font-size: 16px;
    font-weight: bold;
    color: #007bff; /* เปลี่ยนเป็นสีเหลืองเข้ม */
    text-decoration: none;
}

/* ข้อความแจ้งเตือน */
.error, .success {
    width: 100%;
    padding: 12px;
    border-radius: 10px;
    font-weight: bold;
    text-align: center;
    backdrop-filter: blur(10px);
    box-shadow: 4px 4px 8px rgba(0, 0, 0, 0.2);
}

.error {
    background: rgba(255, 50, 50, 0.3);
    color: white;
    border-left: 5px solid red;
}

.success {
    background: rgba(50, 255, 50, 0.3);
    color: white;
    border-left: 5px solid green;
}

/* Responsive */
@media screen and (max-width: 768px) {
    .header, form, .content {
        width: 90%;
    }

    .top-bar .btn-login {
        margin-right: 10px;
        font-size: 14px;
        padding: 10px;
    }
}