:root {
  --bg-main: #f8fafc;
  --bg-card: #ffffff;
  --border-soft: #e2e8f0;
  --primary: #1e3a8a;
  --primary-soft: #e0e7ff;
  --text-main: #0f172a;
  --text-muted: #475569;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Inter", "Segoe UI", system-ui, sans-serif;
  background: linear-gradient(180deg, #f8fafc 0%, #eef2ff 100%);
  color: var(--text-main);
}

.site-logo {
  max-width: 350px;
  margin: auto;
  padding: 18px 20px;
  display: flex;
  justify-content: center;
  align-items: center;
}

.site-header {
  background: #ffffff;
  border-bottom: 1px solid var(--border-soft);
  margin-bottom: 20px;
}

.container {
  max-width: 1100px;
  margin: auto;
  padding: 40px 20px 80px 20px;
}

h1 {
  text-align: center;
  font-size: 34px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 6px;
}

.subtitle {
  text-align: center;
  color: var(--text-muted);
  margin-bottom: 40px;
  font-size: 14px;
}

.calculator {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 26px;
  background: var(--bg-card);
  padding: 36px;
  border-radius: 16px;
  border: 1px solid var(--border-soft);
  box-shadow: 0 10px 25px rgba(15, 23, 42, .08);
}

.field label {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 6px;
  display: block;
  font-weight: 500;
}

.field input,
.field select {
  width: 100%;
  padding: 14px;
  background: #ffffff;
  border: 1px solid var(--border-soft);
  border-radius: 10px;
  color: var(--text-main);
  font-size: 15px;
  transition: .2s;
}

.field input:focus,
.field select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 2px var(--primary-soft);
}

.full {
  grid-column: 1 / -1;
}

button {
  width: 100%;
  padding: 15px;
  border-radius: 12px;
  border: none;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  background: var(--primary);
  color: #ffffff;
  transition: .2s;
}

button:hover {
  background: #1e40af;
  box-shadow: 0 6px 14px rgba(30, 58, 138, .25);
}

.result-box {
  margin-top: 35px;
  padding: 28px;
  border-radius: 16px;
  background: #f8fafc;
  border: 1px solid var(--border-soft);
}

.result-box h3 {
  margin-top: 0;
  font-size: 20px;
  color: var(--primary);
}

.note {
  margin-top: 10px;
  font-size: 12px;
  color: var(--text-muted);
}

.whatsapp-btn {
  position: fixed;
  right: 20px;
  bottom: 20px;
  background: #25d366;
  color: #fff;
  padding: 14px 18px;
  border-radius: 50px;
  font-weight: 600;
  text-decoration: none;
  box-shadow: 0 6px 16px rgba(0, 0, 0, .25);
  z-index: 9999;
}

@media(max-width: 900px) {
  .calculator {
    grid-template-columns: 1fr;
  }
  h1 {
    font-size: 28px;
  }
}







/* Başlık bölümü tasarımı */
.header-section {
  text-align: center;
  margin-bottom: 30px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-soft);
}

.header-section h1 {
  font-size: 24px; /* Başlığı biraz küçülterek daha profesyonel kıldık */
  margin-bottom: 10px;
}

.header-section .subtitle {
  margin-bottom: 0;
  font-size: 14px;
  color: var(--text-muted);
}












.top-banner-grid {
  display: grid;
  grid-template-columns: 1fr 1fr; /* İki kutu da tam eşit genişlikte (yarı yarıya) */
  gap: 20px;
  margin-bottom: 26px;
}

.header-box, .info-box {
  background: #ffffff;
  border: 1px solid var(--border-soft);
  padding: 24px;
  border-radius: 16px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.03);
}

.header-box {
  border-left: 5px solid var(--primary);
  text-align: left;
}

.header-box h1 {
  margin: 0 0 8px 0;
  font-size: 20px;
  color: var(--primary);
  text-align: left;
}

.header-box p, .info-box p {
  margin: 0;
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.6;
}

.info-box h3 {
  margin: 0 0 8px 0;
  font-size: 16px;
  color: #0f172a;
}

/* Mobilde alt alta gelsin */
@media(max-width: 900px) {
  .top-banner-grid {
    grid-template-columns: 1fr;
  }
}












/* Header altındaki tüm boşlukları zorla sıfırlar */
.site-header {
  margin-bottom: 0 !important;
  padding-bottom: 0 !important;
  border-bottom: none !important;
}

/* Sayfa içeriğinin üst boşluğunu daraltır */
.container {
  padding-top: 15px !important;
}













/* Logo Siyah-Beyaz Geçiş Efekti */
.site-logo {
  filter: grayscale(0%); /* Başlangıçta normal (renkli) */
  transition: all 0.4s ease; /* Yumuşak bir geçiş sağlar */
  cursor: pointer;
}

.site-logo:hover {
  filter: grayscale(100%); /* Üzerine gelince tamamen siyah-beyaz olur */
  transform: scale(1.02); /* Üzerine gelince hafifçe büyür, daha belirgin olur */
}