@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600&display=swap');

:root {
    --color-kale-navy: #0d1b2a;
    --color-kale-blue: #2b6cb0;
    --color-bg: #f7f9fc;
    --color-text: #1a1a1a;
    --color-muted: #5b6676;
    --radius-lg: 15px;
    --shadow-soft: 0 10px 30px rgba(0,0,0,0.08);
    --shadow-hover: 0 16px 40px rgba(0,0,0,0.14);
    --border-soft: 1px solid rgba(15, 23, 42, 0.08);

    /* FAQ */
    --faq-border: rgba(43, 108, 176, 0.35);
    --faq-bg: #ffffff;
    --faq-icon: #2b6cb0;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: 'Poppins', sans-serif;
    background: var(--color-bg);
    color: var(--color-text);
}

/* ===== Layout ===== */
.container {
    max-width: 1560px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== Slider ===== */
.page-slider {
    position: relative;
    width: 100%;
    height: 450px;
    overflow: hidden;
    background: #000;
}
.page-slider img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
    /* İstek: perde/şerit yok - kalite bozulmasın */
    opacity: 1;
    filter: none;
}
.slider-caption {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    text-align: center;
    width: min(1100px, 92%);
    padding: 0 10px;
}
.slider-caption h1 {
    margin: 0 0 2px 0; /* İstek: boşluğu azalt */
    font-size: 54px;
    font-weight: 700;
    letter-spacing: 1px;
    color: #fff;
    text-shadow: 0 8px 22px rgba(0,0,0,0.45);
}
.slider-caption p {
    margin: 0; /* İstek: satırlar arası boşluk azalsın */
    font-size: 19px; /* İstek: 1 punta büyüt */
    font-weight: 500;
    color: rgba(255,255,255,0.98);
    text-shadow: 0 8px 20px rgba(0,0,0,0.45);
    line-height: 1.35;
}

/* ===== Header Section ===== */
.header-section {
    padding: 40px 0 10px;
    background: #fff;
    border-bottom: var(--border-soft);
}
.main-title {
    font-size: 34px;
    font-weight: 700;
    text-align: center;
    margin: 0;
}
.header-line {
    width: 100px;
    height: 4px;
    background: var(--color-kale-blue);
    margin: 14px auto 18px;
    border-radius: 2px;
}
.intro-text {
    max-width: 1100px;
    margin: 0 auto 8px;
    text-align: center;
    color: var(--color-muted);
    font-size: 16px;
    line-height: 1.7;
}

/* ===== Cards (4 üst menü + 6 ilgili) ===== */
.app-section {
    padding: 34px 0 10px;
    background: var(--color-bg);
}

.container-grid,
.related-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.app-card {
    position: relative;
    display: block;
    height: 380px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    text-decoration: none;
    background: #000;
    box-shadow: var(--shadow-soft);
    border: var(--border-soft);
    transform: translateZ(0); /* render netliği */
}
.app-card:hover {
    box-shadow: var(--shadow-hover);
}
.card-bg {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    transform: scale(1.02);
    transition: transform 0.5s ease;
}
.app-card:hover .card-bg {
    transform: scale(1.06);
}

/* İstek: ekstra perde/overlay yok (görsel kalite bozulmasın) */
.card-overlay { display: none !important; }

.card-content {
    position: absolute;
    inset: 0;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 20px;
}
.card-content h3 {
    margin: 0 0 8px 0;
    color: #fff;
    font-size: 22px;
    font-weight: 700;
    line-height: 1.25;
    /* Yazı okunabilirliği için sadece başlıkta şerit (görseli bozmaz) */
    background: rgba(0,0,0,0.55);
    display: inline-block;
    padding: 10px 14px;
    border-radius: 10px;
}
.card-content p {
    margin: 0 0 14px 0;
    color: rgba(255,255,255,0.95);
    font-size: 14px;
    line-height: 1.55;
    max-width: 95%;
    background: rgba(0,0,0,0.40);
    display: inline-block;
    padding: 8px 12px;
    border-radius: 10px;
}
.view-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    width: fit-content;
    background: #00aeef; /* DÜZELTİLDİ: Menü CSS'inden bulunan doğru logo mavisi */
    color: #ffffff;      /* DÜZELTİLDİ: Okunabilirlik için yazı rengi beyaz */
    font-weight: 700;
    font-size: 14px;
    padding: 10px 14px;
    border-radius: 999px;
    transition: background-color 0.3s ease; /* Yumuşak geçiş için eklendi */
}

/* Üzerine gelince daha koyu mavi olsun */
.view-btn:hover {
    background: #0095d6; /* DÜZELTİLDİ: Hover efekti için daha koyu tonu */
}

/* Related cards sizing */
.related-systems {
    padding: 30px 0 40px;
    background: #fff;
    border-top: var(--border-soft);
    border-bottom: var(--border-soft);
}
.center-title {
    font-size: 30px;
    font-weight: 700;
    text-align: center;
    margin: 0;
}
.related-card {
    height: 350px; /* İstek: 350px */
}

/* ===== Technical Guide Section ===== */
.technical-guide-section {
    padding: 20px 0 10px;
}
.content-block {
    background: #fff;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-soft);
    border: var(--border-soft);
    padding: 26px 28px;
    margin-bottom: 22px;
}
.content-block h2 {
    margin: 0 0 14px 0;
    font-size: 22px;
    font-weight: 700;
    color: var(--color-kale-navy);
    padding-left: 14px;
    border-left: 4px solid #00aeef; /* DÜZELTİLDİ: Logo rengiyle uyumlu hale getirildi */
}
.content-block p {
    margin: 0 0 12px 0;
    color: #2a3443;
    line-height: 1.85;
    font-size: 15.5px;
}
.content-block p:last-child { margin-bottom: 0; }

.kale-checklist {
    margin: 14px 0 0;
    padding-left: 20px;
    color: #2a3443;
    line-height: 1.75;
}
.kale-checklist li {
    margin: 8px 0;
}

/* ===== FAQ ===== */
.faq-section {
    padding: 48px 0 64px;
    background: var(--color-bg);
}
.faq-title {
    text-align: center;
    font-size: 30px;
    font-weight: 700;
    margin: 0 0 26px;
    color: var(--color-kale-navy);
}
.accordion {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 14px;
}
.accordion-item {
    background: var(--faq-bg);
    border: 1px solid var(--faq-border);
    border-radius: 14px;
    box-shadow: 0 10px 24px rgba(0,0,0,0.06);
    overflow: hidden;
}
.accordion-header {
    width: 100%;
    text-align: left;
    background: #fff;
    border: 0;
    outline: none;
    cursor: pointer;
    padding: 18px 18px 18px 16px;
    font-family: inherit;
    font-size: 16px;
    font-weight: 700;
    color: #00aeef; /* DÜZELTİLDİ: Logo rengi açık mavi yapıldı */
    display: flex;
    align-items: center;
    justify-content: space-between;

    /* mavi logo tonunda kenar çizgisi */
    border-left: 4px solid rgba(0, 174, 239, 0.55); /* DÜZELTİLDİ: Kenar çizgisi de aynı tonda yapıldı */
}
.accordion-header::after {
    content: "+";
    font-size: 22px;
    line-height: 1;
    color: var(--faq-icon);
    margin-left: 14px;
}
.accordion-header[aria-expanded="true"]::after {
    content: "−";
}
.accordion-body {
    padding: 0 18px;
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.28s ease;
}
.accordion-body p {
    margin: 0;
    padding: 0 0 18px 0;
    color: #2a3443;
    line-height: 1.75;
    font-size: 15px;
}

/* ===== Responsive ===== */
@media (max-width: 1100px) {
    .container-grid,
    .related-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .slider-caption h1 { font-size: 44px; }
}
@media (max-width: 720px) {
    .page-slider { height: 360px; }
    .slider-caption h1 { font-size: 34px; }
    .slider-caption p { font-size: 17px; }
    .container-grid,
    .related-grid {
        grid-template-columns: 1fr;
    }
    .app-card { height: 320px; }
    .related-card { height: 320px; }
    .main-title { font-size: 26px; }
    .center-title { font-size: 24px; }
}