/* --- RENK DEĞİŞKENLERİ (DOĞA TEMASI) --- */
:root {
    --primary-green: #2e7d32;    /* Orman Yeşili */
    --light-green: #66bb6a;      /* Yaprak Yeşili */
    --bg-light: #f1f8e9;         /* Çok Açık Yeşil-Beyaz */
    --card-white: #ffffff;
    --text-main: #263238;        /* Koyu Gri-Yeşil */
    --transition: 0.3s;
}

/* --- DARK MODE RENKLERİ --- */
body.dark-mode {
    --bg-light: #1b2e1b;         /* Çok Koyu Orman Yeşili */
    --card-white: #253b25;       /* Koyu Kart Rengi */
    --text-main: #e8f5e9;        /* Açık Yeşil Yazı */
    --primary-green: #81c784;    /* Daha Açık Yeşil (Karanlıkta parlasın) */
}

/* --- GENEL AYARLAR --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: var(--bg-light);
    color: var(--text-main);
    transition: background-color var(--transition), color var(--transition);
    line-height: 1.6;
    
    /* Arka Plan Resmi ve Okunabilirlik Filtresi */
    background-image: linear-gradient(rgba(241, 248, 233, 0.85), rgba(241, 248, 233, 0.85)), url('https://images.unsplash.com/photo-1542601906990-b4d3fb778b09?q=80&w=1920&auto=format&fit=crop');
    background-size: cover; 
    background-position: center; 
    background-attachment: fixed;
}

body.dark-mode {
    /* Karanlık mod için koyu filtre */
    background-image: linear-gradient(rgba(27, 46, 27, 0.92), rgba(27, 46, 27, 0.92)), url('https://images.unsplash.com/photo-1542601906990-b4d3fb778b09?q=80&w=1920&auto=format&fit=crop');
}

/* --- NAVBAR --- */
.navbar {
    background: linear-gradient(135deg, var(--primary-green), #4caf50);
    padding: 15px 5%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
    color: #ffffff;
}

.navbar h2 {
    font-weight: bold;
    letter-spacing: 1px;
    color: #ffffff;
    text-shadow: 1px 1px 4px rgba(0,0,0,0.4);
    margin: 0;
}

.navbar a {
    color: #ffffff;
    text-decoration: none;
    margin-left: 15px;
    font-weight: 600;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.3);
    transition: var(--transition);
}

.navbar a:hover {
    color: #e8f5e9;
    opacity: 1;
}

/* --- KONTEYNER VE KARTLAR --- */
.container {
    max-width: 1000px;
    margin: 50px auto;
    padding: 20px;
    display: flex;
    justify-content: center;
}

.card {
    background-color: var(--card-white);
    padding: 40px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    width: 100%;
    max-width: 400px;
    text-align: center;
    transition: background-color var(--transition);
}

.card-large {
    max-width: 800px;
}

h2, h1 {
    margin-bottom: 20px;
    color: var(--primary-green);
}

/* --- FORMLAR --- */
input {
    width: 100%;
    padding: 12px 15px;
    margin: 10px 0;
    border: 2px solid #9e9e9e;
    background-color: #fafafa;
    border-radius: 10px;
    outline: none;
    transition: var(--transition);
    color: var(--text-main);
    font-weight: 500;
}

input:focus {
    border-color: var(--primary-green);
    background-color: #ffffff;
    box-shadow: 0 0 8px rgba(46, 125, 50, 0.3);
}

button {
    width: 100%;
    padding: 12px;
    margin-top: 15px;
    border: none;
    border-radius: 10px;
    background: linear-gradient(45deg, var(--primary-green), var(--light-green));
    color: white;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(46, 125, 50, 0.3);
}

/* --- DARK MODE BUTONU --- */
.dark-toggle {
    background: rgba(255,255,255,0.2);
    border: none;
    color: white;
    padding: 8px 12px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.2rem;
    margin-left: 15px;
    width: auto;
    margin-top: 0;
}

/* --- KOYU MOD FORM KUTULARI DÜZELTMESİ --- */
body.dark-mode input {
    background-color: #142414; /* Kutunun içini koyu yeşil/siyah yapar */
    color: #ffffff;            /* Yazıları bembeyaz ve net yapar */
    border-color: #4caf50;     /* Kenarlıkları koyu moda uygun yeşil yapar */
}

body.dark-mode input:focus {
    background-color: #1b2e1b; /* Kutuya tıklanınca hafifçe aydınlanır */
    border-color: #81c784;     /* Tıklanınca kenarlık parlar */
}