:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --secondary-color: #64748b;
    --background-color: #f8fafc;
    --surface-color: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border-color: #e2e8f0;
    --success: #10b981;
    --error: #ef4444;
    --warning: #f59e0b;
    --sidebar-width: 280px;
    --shadow: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --glass-bg: rgba(255, 255, 255, 0.7);
    --glass-border: rgba(255, 255, 255, 0.3);
}

[data-theme="dark"] {
    --background-color: #0f172a;
    --surface-color: #1e293b;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --border-color: #334155;
    --shadow: 0 20px 25px -5px rgb(0 0 0 / 0.3);
    --glass-bg: rgba(30, 41, 59, 0.7);
    --glass-border: rgba(255, 255, 255, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    line-height: 1.5;
    overflow-x: hidden;
    transition: background-color 0.3s ease, color 0.3s ease;
}

/* Login Page */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--background-color);
    padding: 1.5rem;
}

.login-card {
    background: var(--surface-color);
    width: 100%;
    max-width: 400px;
    padding: 2.5rem;
    border-radius: 1.5rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    text-align: center;
    animation: fadeInUp 0.5s ease;
}

.login-card h1 {
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
    letter-spacing: -0.02em;
}

.login-card p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 0.95rem;
}

.login-card .form-group {
    text-align: left;
    margin-bottom: 1.5rem;
}

.login-card label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.login-card .btn-primary {
    width: 100%;
    margin-top: 1rem;
    padding: 0.875rem;
}

/* Animations */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

.animate-fade { animation: fadeInUp 0.4s ease-out forwards; }

/* Layout - Mobile First */
.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

.main-content {
    flex: 1;
    padding: 1.25rem;
    width: 100%;
    margin-top: 60px; /* Space for mobile header */
    transition: all 0.3s ease;
    display: flex;
    flex-direction: column;
}

#page-content {
    flex: 1;
    width: 100%;
    max-width: 1400px;
    margin: 0 auto;
}

/* Desktop Sidebar Overrides */
@media (min-width: 1025px) {
    .app-container { flex-direction: row; }
    .main-content { 
        margin-left: var(--sidebar-width); 
        margin-top: 0;
        padding: 2.5rem;
    }
}

/* Common Components */
.card {
    background: var(--surface-color);
    border-radius: 1rem;
    padding: 1.25rem;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
    margin-bottom: 1.5rem;
}

.glass {
    background: var(--glass-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--glass-border);
}

/* Grid Layouts */
.stats-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 1.5rem;
    margin-bottom: 2rem;
}

@media (min-width: 640px) {
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1280px) {
    .stats-grid { grid-template-columns: repeat(4, 1fr); }
}

.stat-card {
    background: var(--surface-color);
    padding: 1.5rem;
    border-radius: 1.25rem;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow);
    transition: transform 0.2s ease;
}

.stat-card:hover { transform: translateY(-4px); }

.stat-card .label {
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.stat-card .value {
    font-size: 1.5rem;
    font-weight: 800;
    color: var(--text-primary);
}

/* Responsive Tables */
.scrollable-box {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    border-radius: 0.75rem;
    border: 1px solid var(--border-color);
}

table {
    width: 100%;
    min-width: 600px; /* Prevent shrinking too much */
    border-collapse: collapse;
}

/* Forms */
.form-row {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

@media (min-width: 768px) {
    .form-row { flex-direction: row; }
    .col { flex: 1; }
}

.form-group { margin-bottom: 1.25rem; }

.form-control {
    width: 100%;
    padding: 0.75rem 1rem;
    background-color: var(--background-color);
    border: 1px solid var(--border-color);
    border-radius: 0.75rem;
    color: var(--text-primary);
    font-size: 0.95rem;
}

/* Buttons */
.btn {
    padding: 0.75rem 1.25rem;
    border-radius: 0.75rem;
    font-weight: 600;
    cursor: pointer;
    border: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    font-size: 0.9rem;
    white-space: nowrap;
}

.btn-primary { background: var(--primary-color); color: white; }
.btn-secondary { background: var(--border-color); color: var(--text-primary); }

/* SVG Icons */
.icon-svg { width: 20px; height: 20px; stroke: currentColor; stroke-width: 2; fill: none; }

/* Loading Spinner */
.loading-screen {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: var(--background-color);
    display: flex; justify-content: center; align-items: center;
    z-index: 10000;
}

.spinner {
    width: 40px; height: 40px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

/* Toasts */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    padding: 1rem 2rem;
    border-radius: 1rem;
    color: white;
    font-weight: 600;
    box-shadow: 0 10px 25px rgba(0,0,0,0.2);
    z-index: 10000;
}

.toast-success { background: var(--success); }
.toast-error { background: var(--error); }

.animate-fade-up {
    animation: fadeUp 0.4s ease-out;
}

.fade-out {
    opacity: 0;
    transition: opacity 0.5s ease;
}

@keyframes fadeUp {
    from { opacity: 0; transform: translate(-50%, 20px); }
    to { opacity: 1; transform: translate(-50%, 0); }
}

@keyframes spin { to { transform: rotate(360deg); } }