/* ==========================================================================
   UPAY Kurumsal Tanıtım Web Sitesi CSS Tasarım Sistemi (Light Theme)
   ========================================================================== */

/* Renk Değişkenleri ve Tasarım Değerleri */
:root {
    /* Kurumsal Renk Paleti (Light Theme) */
    --color-primary: #1e3a8a;       /* Derin Mavi / Lacivert */
    --color-primary-light: #eff6ff; /* Çok Açık Mavi */
    --color-primary-hover: #1e40af; /* Orta Mavi */
    --color-accent: #2563eb;        /* İndigo / Elektrik Mavisi */
    --color-accent-hover: #1d4ed8;
    
    --color-gold: #d97706;          /* Kurumsal Altın / Kehribar */
    --color-gold-light: #fef3c7;    /* Açık Kehribar */
    --color-gold-dark: #b45309;     /* Koyu Kehribar */

    --color-emerald: #059669;       /* Zümrüt Yeşili (Başarı/Aktif) */
    --color-emerald-light: #ecfdf5; /* Açık Zümrüt Yeşili */
    
    /* Arka Plan ve Metin Tonları */
    --bg-main: #f8fafc;             /* Çok Açık Gri / Maviye Çalan */
    --bg-card: #ffffff;             /* Saf Beyaz */
    --text-main: #1e293b;           /* Koyu Antrasit */
    --text-muted: #64748b;          /* Orta Gri / Muted */
    --text-light: #94a3b8;          /* Açık Gri */
    --border-color: #e2e8f0;        /* Kenarlık Rengi */
    
    /* Gölgeler ve Köşeler */
    --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(15, 23, 42, 0.08), 0 2px 4px -2px rgba(15, 23, 42, 0.08);
    --shadow-lg: 0 10px 25px -5px rgba(15, 23, 42, 0.06), 0 8px 10px -6px rgba(15, 23, 42, 0.06);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 20px;
    
    /* Geçişler */
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Temel Sıfırlamalar */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent; /* Mobil tıklama mavi kutu engelleme */
}

html, body {
    width: 100%;
    height: 100%;
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-main);
    color: var(--text-main);
    line-height: 1.6;
    overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
    font-family: 'Outfit', sans-serif;
    font-weight: 700;
    color: var(--color-primary);
}

/* ==========================================================================
   BİLEŞENLER (COMPONENTS)
   ========================================================================== */

/* Buton Stilleri */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 24px;
    border-radius: var(--radius-md);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
    border: none;
    outline: none;
    text-decoration: none;
}

.btn:active {
    transform: scale(0.96); /* Touch feedback */
}

.btn-primary {
    background-color: var(--color-primary);
    color: #ffffff;
}

.btn-primary:hover {
    background-color: var(--color-primary-hover);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background-color: var(--bg-card);
    color: var(--color-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background-color: var(--bg-main);
    border-color: var(--text-light);
}

.btn-outline {
    background-color: transparent;
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
}

.btn-outline:hover {
    background-color: var(--color-primary-light);
}

.btn-sm {
    padding: 8px 16px;
    font-size: 13px;
    border-radius: var(--radius-sm);
}

.btn-xs {
    padding: 6px 12px;
    font-size: 12px;
    border-radius: var(--radius-sm);
}

.btn-icon {
    width: 18px;
    height: 18px;
    flex-shrink: 0;
}

/* Badge / Rozetler */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 12px;
}

.badge-amber {
    background-color: var(--color-gold-light);
    color: var(--color-gold-dark);
}

.badge-emerald {
    background-color: var(--color-emerald-light);
    color: var(--color-emerald);
}

/* ==========================================================================
   HEADER / NAVİGASYON (DESKTOP)
   ========================================================================== */
.desktop-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 70px;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 100;
    display: block;
}

.header-container {
    max-width: 1200px;
    height: 100%;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-svg {
    width: 32px;
    height: 32px;
}

.logo-text-group {
    display: flex;
    flex-direction: column;
}

.logo-title {
    font-family: 'Outfit', sans-serif;
    font-size: 20px;
    font-weight: 900;
    color: var(--color-primary);
    line-height: 1;
    letter-spacing: 0.5px;
}

.logo-subtitle {
    font-size: 10px;
    color: var(--text-muted);
    font-weight: 500;
    margin-top: 2px;
}

.desktop-nav {
    display: flex;
    gap: 8px;
}

.desktop-nav .nav-link {
    background: transparent;
    border: none;
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
}

.desktop-nav .nav-link:hover {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
}

.desktop-nav .nav-link.active {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
}

/* ==========================================================================
   SAYFA GEÇİŞ VE YÖNETİM (SPA)
   ========================================================================== */
.app-main-content {
    max-width: 1200px;
    margin: 90px auto 40px; /* Header için üst boşluk */
    padding: 0 24px;
}

.page-section {
    display: none;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.page-section.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
    animation: fadeInUp 0.35s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ==========================================================================
   SECTION 1: HERO VE GENEL BAKIŞ
   ========================================================================== */
.hero-block {
    text-align: center;
    padding: 40px 0 20px;
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 46px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 16px;
    letter-spacing: -1px;
}

.highlight-blue {
    color: var(--color-accent);
    position: relative;
    display: inline-block;
}

.hero-subtitle {
    font-size: 17px;
    color: var(--text-muted);
    margin-bottom: 30px;
    line-height: 1.6;
}

.hero-cta-group {
    display: flex;
    justify-content: center;
    gap: 16px;
}

/* İnteraktif Simülatör Kartı */
.simulator-card {
    background-color: var(--bg-card);
    border-radius: var(--radius-lg);
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-lg);
    margin: 40px 0;
    overflow: hidden;
}

.simulator-header {
    background-color: #f1f5f9;
    padding: 14px 20px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.simulator-status {
    display: flex;
    align-items: center;
    gap: 8px;
}

.pulse-indicator {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    display: inline-block;
}

.status-active {
    background-color: var(--color-emerald);
    box-shadow: 0 0 0 4px rgba(5, 150, 105, 0.2);
    animation: pulseSim 1.5s infinite;
}

@keyframes pulseSim {
    0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(5, 150, 105, 0.4); }
    70% { transform: scale(1); box-shadow: 0 0 0 8px rgba(5, 150, 105, 0); }
    100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(5, 150, 105, 0); }
}

.simulator-status-text {
    font-size: 13px;
    font-weight: 700;
    color: var(--color-primary);
}

.simulator-body {
    padding: 30px 24px;
}

.sim-grid {
    display: grid;
    grid-template-columns: 1fr 1.2fr 1fr;
    align-items: center;
    gap: 20px;
    margin-bottom: 30px;
}

.sim-node {
    background-color: var(--bg-main);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px 16px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: var(--transition-normal);
}

.node-icon-wrapper {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background-color: var(--bg-card);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    margin-bottom: 12px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-normal);
}

.node-svg {
    width: 30px;
    height: 30px;
}

.node-label {
    font-size: 14px;
    font-weight: 800;
    color: var(--color-primary);
    margin-bottom: 4px;
}

.node-sub {
    font-size: 11px;
    color: var(--text-muted);
    margin-bottom: 12px;
}

.node-badge {
    padding: 4px 10px;
    border-radius: 12px;
    font-size: 10px;
    font-weight: 700;
    background-color: var(--border-color);
    color: var(--text-muted);
    text-transform: uppercase;
}

/* Aktif Simülasyon Durumları */
.sim-node.active-host {
    border-color: var(--color-accent);
    background-color: var(--color-primary-light);
}

.sim-node.active-host .node-icon-wrapper {
    background-color: var(--color-accent);
    color: #ffffff;
    box-shadow: 0 0 15px rgba(37, 99, 235, 0.3);
}

.sim-node.active-host #host-badge {
    background-color: var(--color-accent);
    color: #ffffff;
}

.sim-node.active-guest {
    border-color: var(--color-emerald);
    background-color: var(--color-emerald-light);
}

.sim-node.active-guest .node-icon-wrapper {
    background-color: var(--color-emerald);
    color: #ffffff;
    box-shadow: 0 0 15px rgba(5, 150, 105, 0.3);
}

.sim-node.active-guest #guest-badge {
    background-color: var(--color-emerald);
    color: #ffffff;
}

/* Bağlantı Kanalı */
.sim-channel {
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.channel-line {
    width: 100%;
    height: 4px;
    background-color: var(--border-color);
    border-radius: 2px;
    position: relative;
    overflow: hidden;
    margin-bottom: 12px;
}

.channel-flow {
    position: absolute;
    width: 30%;
    height: 100%;
    background: linear-gradient(90deg, transparent, var(--color-accent), transparent);
    left: -30%;
    display: none;
}

.channel-flow.active {
    display: block;
    animation: flowAnim 1.8s infinite linear;
}

@keyframes flowAnim {
    0% { left: -30%; }
    100% { left: 100%; }
}

.channel-flow.active-reverse {
    display: block;
    animation: flowAnimReverse 1.8s infinite linear;
    background: linear-gradient(90deg, transparent, var(--color-gold), transparent);
}

@keyframes flowAnimReverse {
    0% { right: -30%; left: auto; }
    100% { right: 100%; left: auto; }
}

.channel-info {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.channel-code {
    font-family: monospace;
    font-size: 15px;
    font-weight: 800;
    letter-spacing: 1px;
    color: var(--color-primary);
    background-color: var(--bg-main);
    padding: 4px 12px;
    border-radius: 6px;
    border: 1px solid var(--border-color);
}

.channel-encryption {
    font-size: 9px;
    font-weight: 700;
    color: var(--color-emerald);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Simülasyon Kontrolleri */
.simulator-controls {
    border-top: 1px solid var(--border-color);
    padding-top: 20px;
    text-align: center;
}

.sim-step-text {
    font-size: 14px;
    color: var(--text-main);
    font-weight: 500;
    margin-bottom: 14px;
    min-height: 44px; /* Yükseklik zıplamasını önlemek için */
}

.sim-action-row {
    display: flex;
    justify-content: center;
}

/* Klasik Grid Avantajları */
.features-grid-classic {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 40px;
}

.feature-card-flat {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 30px 24px;
    box-shadow: var(--shadow-sm);
    transition: var(--transition-normal);
}

.feature-card-flat:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--text-light);
}

.feat-icon-box {
    width: 46px;
    height: 46px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 18px;
}

.feat-svg {
    width: 24px;
    height: 24px;
}

.bg-blue-light { background-color: var(--color-primary-light); }
.text-blue { color: var(--color-accent); }
.bg-emerald-light { background-color: var(--color-emerald-light); }
.text-emerald { color: var(--color-emerald); }
.bg-amber-light { background-color: var(--color-gold-light); }
.text-amber { color: var(--color-gold); }

.feature-card-flat h3 {
    font-size: 18px;
    margin-bottom: 8px;
}

.feature-card-flat p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.5;
}

/* ==========================================================================
   SECTIONS: DETAY SAYFALARI (EKLENTİ & İMZACI)
   ========================================================================== */
.section-title-wrapper {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 30px;
}

.section-badge {
    font-size: 11px;
    font-weight: 800;
    color: var(--color-accent);
    letter-spacing: 1px;
    text-transform: uppercase;
}

.section-title {
    font-size: 32px;
    font-weight: 800;
    margin: 4px 0 10px;
}

.section-subtitle {
    font-size: 15px;
    color: var(--text-muted);
}

.detail-split, .detail-split-reverse {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 40px;
    align-items: center;
    margin-top: 40px;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 40px;
    box-shadow: var(--shadow-md);
}

.detail-split-reverse {
    grid-template-columns: 1fr 1.2fr;
}

.card-title-group {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 18px;
}

.card-icon-main {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.detail-p {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 16px;
    line-height: 1.6;
}

.detail-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 12px;
    margin-top: 20px;
}

.detail-list li {
    display: flex;
    gap: 10px;
    align-items: flex-start;
    font-size: 13px;
    color: var(--text-main);
}

.check-icon {
    width: 18px;
    height: 18px;
    color: var(--color-emerald);
    flex-shrink: 0;
    margin-top: 2px;
}

.check-icon.icon-amber {
    color: var(--color-gold);
}

/* Teknik Tablo / Özellik Kartı */
.tech-spec-card {
    background-color: var(--bg-main);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    border-top: 6px solid var(--color-accent);
}

.tech-spec-card.spec-amber {
    border-top-color: var(--color-gold);
}

.tech-spec-card h4 {
    font-size: 16px;
    margin-bottom: 18px;
    font-weight: 800;
}

.spec-row {
    display: flex;
    justify-content: space-between;
    padding: 10px 0;
    border-bottom: 1px solid var(--border-color);
    font-size: 12px;
}

.spec-row:last-child {
    border-bottom: none;
}

.spec-name {
    font-weight: 700;
    color: var(--color-primary);
}

.spec-value {
    color: var(--text-muted);
    text-align: right;
    font-weight: 500;
}

/* ==========================================================================
   SECTION 4: NASIL ÇALIŞIR?
   ========================================================================== */
.steps-flow-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    margin-top: 40px;
}

.step-flow-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px 16px;
    text-align: center;
    flex: 1;
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
    min-height: 250px;
    box-shadow: var(--shadow-sm);
}

.step-number {
    position: absolute;
    top: -12px;
    background-color: var(--color-primary);
    color: #ffffff;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 11px;
    font-weight: 800;
    box-shadow: var(--shadow-sm);
}

.step-icon-wrapper {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 14px;
}

.step-flow-card h4 {
    font-size: 14px;
    margin-bottom: 8px;
}

.step-flow-card p {
    font-size: 11px;
    color: var(--text-muted);
    line-height: 1.5;
}

.step-flow-arrow {
    color: var(--text-light);
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ==========================================================================
   SECTION 5: GÜVENLİK
   ========================================================================== */
.security-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
    margin-top: 40px;
}

.security-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 24px;
    display: flex;
    gap: 16px;
    box-shadow: var(--shadow-sm);
}

.sec-icon {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.security-card h4 {
    font-size: 15px;
    margin-bottom: 6px;
    font-weight: 800;
}

.security-card p {
    font-size: 12px;
    color: var(--text-muted);
    line-height: 1.5;
}

/* ==========================================================================
   FOOTER / ALT BİLGİ
   ========================================================================== */
.app-footer {
    background-color: var(--color-primary);
    color: #ffffff;
    text-align: center;
    padding: 40px 24px;
    margin-top: 60px;
}

.footer-container {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.footer-logo {
    font-family: 'Outfit', sans-serif;
    font-size: 24px;
    font-weight: 900;
    letter-spacing: 0.5px;
}

.app-footer p {
    font-size: 12px;
    opacity: 0.8;
}

.license-note {
    font-size: 10px !important;
    opacity: 0.6 !important;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 10px;
    margin-top: 4px;
}

.copyright {
    font-size: 11px !important;
    opacity: 0.5 !important;
    margin-top: 8px;
}

/* ==========================================================================
   NAVİGASYON (MOBİL - BOTTOM BAR)
   ========================================================================== */
.mobile-bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    height: 60px;
    background-color: rgba(255, 255, 255, 0.96);
    backdrop-filter: blur(10px);
    border-top: 1px solid var(--border-color);
    display: none; /* Desktopta gizle */
    justify-content: space-around;
    align-items: center;
    z-index: 100;
    padding-bottom: env(safe-area-inset-bottom); /* iOS çentik koruması */
}

.nav-item {
    background: transparent;
    border: none;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    cursor: pointer;
    font-weight: 700;
    font-size: 9px;
    transition: var(--transition-fast);
    flex: 1;
    height: 100%;
}

.nav-item-icon {
    width: 20px;
    height: 20px;
    margin-bottom: 2px;
    transition: var(--transition-fast);
}

.nav-item:active .nav-item-icon {
    transform: scale(0.85);
}

.nav-item.active {
    color: var(--color-primary);
}

.nav-item.active .nav-item-icon {
    stroke-width: 2.5;
}

/* ==========================================================================
   RESPONSIVE UYUMLULUK (MEDIA QUERIES)
   ========================================================================== */

/* Tablet & Mobil Görünüm (992px altı) */
@media (max-width: 992px) {
    .detail-split, .detail-split-reverse {
        grid-template-columns: 1fr;
        padding: 24px;
    }
    
    .detail-split-reverse {
        grid-template-columns: 1fr;
    }
    
    .detail-split-reverse .detail-features-side {
        order: 2; /* Mobilde tabloyu aşağıya at */
    }
    
    .hero-title {
        font-size: 34px;
    }
    
    .sim-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    
    .sim-channel {
        transform: rotate(90deg);
        margin: 20px 0;
        height: 60px;
    }
    
    .sim-channel .channel-info {
        transform: rotate(-90deg);
        margin-top: -10px;
    }
    
    .steps-flow-container {
        flex-direction: column;
        gap: 16px;
    }
    
    .step-flow-arrow {
        transform: rotate(90deg);
        margin: 8px 0;
    }
    
    .step-flow-card {
        width: 100%;
        min-height: auto;
    }
    
    .security-grid {
        grid-template-columns: 1fr;
    }
    
    .features-grid-classic {
        grid-template-columns: 1fr;
    }
}

/* Saf Mobil Görünüm (768px altı) */
@media (max-width: 768px) {
    /* Header ve navigasyon değişimi */
    .desktop-header {
        display: none; /* Masaüstü başlığını kapat */
    }
    
    .mobile-bottom-nav {
        display: flex; /* Alt barı aç */
    }
    
    .app-main-content {
        margin-top: 20px; /* Üst boşluğu azalt */
        margin-bottom: 80px; /* Alt bar için boşluk bırak */
    }
    
    .hero-block {
        padding: 20px 0;
    }
    
    .hero-title {
        font-size: 28px;
    }
    
    .hero-subtitle {
        font-size: 14px;
    }
    
    .hero-cta-group {
        flex-direction: column;
        width: 100%;
    }
    
    .hero-cta-group .btn {
        width: 100%;
    }
}