body {
    margin: 0;
    padding: 0;
    font-family: "Verdana", "Geneva", sans-serif; 
    background-color: #e0e0e0;
    background-image: linear-gradient(45deg, #d4d4d4 25%, transparent 25%, transparent 75%, #d4d4d4 75%, #d4d4d4), 
                      linear-gradient(45deg, #d4d4d4 25%, transparent 25%, transparent 75%, #d4d4d4 75%, #d4d4d4);
    background-size: 20px 20px;
    background-position: 0 0, 10px 10px;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.container {
    background: #ffffff;
    width: 350px;
    padding: 30px;
    border: 1px solid #ccc;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
    text-align: center;
}

h2, h1 {
    color: #333;
    text-shadow: 1px 1px 0px #fff;
    margin-bottom: 20px;
    border-bottom: 1px dashed #ccc;
    padding-bottom: 10px;
}

input[type="text"], 
input[type="email"], 
input[type="password"] {
    width: 90%;
    padding: 10px;
    margin: 10px 0;
    border: 1px solid #aaa;
    border-radius: 4px;
    background: #f9f9f9;
    box-shadow: inset 0 1px 3px rgba(0,0,0,0.1);
    font-size: 14px;
}

input:focus {
    outline: none;
    border-color: #66afe9;
    box-shadow: 0 0 8px rgba(102, 175, 233, 0.6);
}

button {
    width: 100%;
    padding: 10px;
    margin-top: 15px;
    font-weight: bold;
    color: white;
    cursor: pointer;
    border: 1px solid #20559a;
    border-radius: 20px;
    
    /* Mavi Gradyan Geçiş */
    background: #2980b9; 
    background: linear-gradient(to bottom, #6db3f2 0%, #54a3ee 50%, #3690f0 51%, #1e69de 100%);
    
    text-shadow: 0 -1px 0 rgba(0,0,0,0.5);
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
    font-size: 16px;
}

button:hover {
    background: linear-gradient(to bottom, #4f9eea 0%, #3a8cdf 50%, #207ce5 51%, #0d58c1 100%);
}

button:active {
    position: relative;
    top: 1px;
    box-shadow: inset 0 2px 5px rgba(0,0,0,0.4);
}

a {
    color: #0066cc;
    text-decoration: none;
    font-size: 12px;
}

a:hover {
    text-decoration: underline;
    color: #ff6600;
}

.mesaj-kutu {
    padding: 10px;
    margin-bottom: 15px;
    border-radius: 5px;
    font-size: 13px;
    font-weight: bold;
}

.hata {
    background-color: #ffdddd;
    border: 1px solid #ffaaaa;
    color: #990000;
}

.basari {
    background-color: #ddffdd;
    border: 1px solid #aaffaa;
    color: #006600;
}