:root {
    --primary-bg: #f8fafc;
    --card-bg: rgba(255, 255, 255, 0.85);
    --text-main: #0f172a;
    --text-muted: #64748b;
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --border-color: rgba(226, 232, 240, 0.8);
    --glass-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.07);
    --transition: all 0.3s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background: linear-gradient(135deg, #e0e7ff 0%, #fefafe 100%);
    color: var(--text-main);
    min-height: 100vh;
    overflow-x: hidden;
}

/* Glass Panel Utility */
.glass-panel {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    box-shadow: var(--glass-shadow);
}

/* Login Page */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}
.login-card {
    width: 100%;
    max-width: 400px;
    padding: 40px;
    text-align: center;
}
.login-card .logo-area {
    font-size: 48px;
    color: var(--primary-color);
    margin-bottom: 20px;
}
.login-card h2 {
    font-size: 24px;
    margin-top: 10px;
    color: var(--text-main);
}
.login-card h3 {
    font-size: 16px;
    font-weight: 500;
    color: var(--text-muted);
    margin-bottom: 30px;
}

/* Forms */
.input-group {
    position: relative;
    margin-bottom: 20px;
}
.input-group i {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}
.input-group input, .form-group input, .form-group textarea {
    width: 100%;
    padding: 12px 15px;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    font-size: 14px;
    transition: var(--transition);
    background: white;
}
.input-group input {
    padding-left: 45px;
}
.input-group input:focus, .form-group input:focus, .form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}
.form-group {
    margin-bottom: 15px;
    text-align: left;
}
.form-group label {
    display: block;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 5px;
    color: var(--text-muted);
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 14px;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    text-align: center;
}
.w-100 { width: 100%; }
.btn-primary { background: var(--primary-color); color: white; }
.btn-primary:hover { background: var(--primary-hover); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(59,130,246,0.3); }
.btn-success { background: var(--success-color); color: white; }
.btn-success:hover { background: #059669; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(16,185,129,0.3); }
.btn-danger { background: var(--error-color); color: white; padding: 6px 12px; font-size: 12px;}
.btn-danger:hover { background: #dc2626; }
.btn-sm { padding: 6px 12px; font-size: 12px; }

/* Navbar */
.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 30px;
    margin: 20px auto;
    width: 95%;
    max-width: 1200px;
    border-radius: 12px;
}
.nav-brand {
    font-size: 18px;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 10px;
}
.btn-logout {
    background: transparent;
    color: var(--text-muted);
    border: 1px solid var(--border-color);
}
.btn-logout:hover {
    background: var(--error-color);
    color: white;
    border-color: var(--error-color);
}

/* Layout Container */
.app-container {
    width: 95%;
    max-width: 1200px;
    margin: 0 auto 40px auto;
}
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
}
.app-header h1 { font-size: 28px; }
.subtitle { color: var(--text-muted); font-size: 14px; margin-top: 4px; }

/* Stats Grid */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}
.stat-card {
    padding: 20px;
    display: flex;
    align-items: center;
    gap: 15px;
}
.stat-icon {
    width: 50px;
    height: 50px;
    border-radius: 12px;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 20px;
}
.stat-icon.info { background: rgba(59,130,246,0.1); color: var(--primary-color); }
.stat-icon.success { background: rgba(16,185,129,0.1); color: var(--success-color); }
.stat-icon.warning { background: rgba(245,158,11,0.1); color: var(--warning-color); }
.stat-icon.primary { background: rgba(99,102,241,0.1); color: #6366f1; }

.stat-content h3 { font-size: 13px; color: var(--text-muted); font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px;}
.stat-content p { font-size: 24px; font-weight: 700; color: var(--text-main); margin-top: 5px; }

/* Table Section */
.table-container {
    padding: 25px;
}
.table-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}
.search-box {
    position: relative;
    width: 300px;
}
.search-box i {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
}
.search-box input {
    width: 100%;
    padding: 10px 10px 10px 35px;
    border-radius: 20px;
    border: 1px solid var(--border-color);
    background: rgba(255,255,255,0.5);
    transition: var(--transition);
}
.search-box input:focus {
    background: white;
    outline: none;
    border-color: var(--primary-color);
}

.table-responsive {
    overflow-x: auto;
}
table {
    width: 100%;
    border-collapse: collapse;
}
th, td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}
th {
    font-size: 13px;
    text-transform: uppercase;
    color: var(--text-muted);
    font-weight: 600;
    background: rgba(248, 250, 252, 0.5);
}
tbody tr:hover {
    background: rgba(248, 250, 252, 0.8);
}
td { font-size: 14px; font-weight: 500; }

.text-error { color: var(--error-color); font-weight: 700; }

/* Status Badges */
.badge {
    padding: 6px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 600;
    display: inline-block;
}
.badge.tamamlandi { background: rgba(16,185,129,0.1); color: var(--success-color); }
.badge.eksik { background: rgba(245,158,11,0.1); color: var(--warning-color); }
.badge.odenmedi { background: rgba(239,68,68,0.1); color: var(--error-color); }

/* Modals */
.modal-overlay {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(15, 23, 42, 0.4);
    backdrop-filter: blur(4px);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    transition: opacity 0.3s ease;
}
.modal-overlay.active {
    display: flex;
    opacity: 1;
}
.modal {
    width: 90%;
    max-width: 500px;
    transform: scale(0.9);
    transition: transform 0.3s ease;
}
.modal-overlay.active .modal {
    transform: scale(1);
}
.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 25px;
    border-bottom: 1px solid var(--border-color);
}
.modal-header h2 { font-size: 18px; }
.close-btn {
    background: none;
    border: none;
    font-size: 20px;
    color: var(--text-muted);
    cursor: pointer;
}
.modal-body {
    padding: 25px;
}
.payment-info {
    background: rgba(59,130,246,0.05);
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 20px;
    border-left: 4px solid var(--primary-color);
}
.payment-info p { margin-bottom: 5px; font-size: 14px; }

/* Toast */
.toast {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: white;
    color: var(--text-main);
    padding: 15px 25px;
    border-radius: 8px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    transform: translateY(100px);
    opacity: 0;
    transition: all 0.3s cubic-bezier(0.68, -0.55, 0.265, 1.55);
    z-index: 2000;
    font-weight: 500;
    border-left: 4px solid var(--primary-color);
}
.toast.show {
    transform: translateY(0);
    opacity: 1;
}
.toast.bg-success { border-left-color: var(--success-color); }
.toast.bg-error { border-left-color: var(--error-color); }

@media (max-width: 768px) {
    .app-header { flex-direction: column; align-items: flex-start; gap: 15px; }
    .table-header { flex-direction: column; align-items: flex-start; gap: 15px; }
    .search-box { width: 100%; }
}