/* ===== VARIABLES ===== */
:root {
    /* Colors */
    --color-bg-primary: #1a2332;
    --color-bg-secondary: #232d3f;
    --color-bg-card: #2a3647;
    --color-bg-card-hover: #313e52;

    --color-accent-primary: #00d9ff;
    --color-accent-secondary: #00b4d8;
    --color-accent-gradient: linear-gradient(135deg, #00d9ff 0%, #00b4d8 100%);

    --color-text-primary: #ffffff;
    --color-text-secondary: #a8b3c1;
    --color-text-tertiary: #6b7a8f;

    --color-success: #00e676;
    --color-warning: #ffab00;
    --color-error: #ff5252;
    --color-info: #2979ff;

    /* Spacing */
    --spacing-xs: 8px;
    --spacing-sm: 12px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;

    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-round: 50%;

    /* Shadows */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.2);
    --shadow-glow: 0 0 20px rgba(0, 217, 255, 0.3);

    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;

    /* Z-index */
    --z-nav: 100;
    --z-header: 90;
    --z-modal: 1000;
    --z-toast: 2000;
    --z-loading: 3000;
}

/* ===== RESET & BASE ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--color-bg-primary);
    color: var(--color-text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--color-bg-card);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-bg-card-hover);
}

/* ===== APP CONTAINER ===== */
.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-width: 600px;
    margin: 0 auto;
    background: var(--color-bg-primary);
}

/* ===== HEADER ===== */
.app-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: var(--z-header);
    background: var(--color-bg-primary);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(20px);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-lg);
    max-width: 600px;
    margin: 0 auto;
}

.header-title {
    display: flex;
    flex-direction: column;
}

.header-subtitle {
    font-size: 11px;
    font-weight: 500;
    letter-spacing: 1.5px;
    text-transform: uppercase;
    color: var(--color-text-tertiary);
    margin-bottom: 2px;
}

.header-main-title {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-text-primary);
}

.admin-badge {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-xs) var(--spacing-md);
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 20px;
    color: var(--color-text-secondary);
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.admin-badge:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: rgba(255, 255, 255, 0.15);
}

.admin-badge svg {
    width: 16px;
    height: 16px;
}

/* ===== MAIN CONTENT ===== */
.app-main {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 80px var(--spacing-lg) 100px;
    max-width: 600px;
    margin: 0 auto;
    width: 100%;
}

/* ===== BOTTOM NAVIGATION ===== */
.bottom-nav {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    z-index: var(--z-nav);
    display: flex;
    justify-content: space-around;
    background: var(--color-bg-secondary);
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    padding: var(--spacing-sm) 0;
    backdrop-filter: blur(20px);
    max-width: 600px;
    margin: 0 auto;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    flex: 1;
    padding: var(--spacing-xs) var(--spacing-sm);
    background: none;
    border: none;
    color: var(--color-text-tertiary);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.nav-item::before {
    content: '';
    position: absolute;
    top: -1px;
    left: 50%;
    transform: translateX(-50%) scaleX(0);
    width: 40px;
    height: 3px;
    background: var(--color-accent-gradient);
    border-radius: 0 0 3px 3px;
    transition: transform var(--transition-normal);
}

.nav-item.active::before {
    transform: translateX(-50%) scaleX(1);
}

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

.nav-icon {
    width: 24px;
    height: 24px;
    transition: transform var(--transition-fast);
}

.nav-item.active .nav-icon {
    transform: scale(1.1);
}

.nav-label {
    font-size: 11px;
    font-weight: 500;
}

/* ===== LOADING OVERLAY ===== */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: var(--z-loading);
    background: rgba(26, 35, 50, 0.95);
    display: none;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(10px);
}

.loading-overlay.active {
    display: flex;
}

.loading-spinner {
    width: 48px;
    height: 48px;
    border: 3px solid rgba(255, 255, 255, 0.1);
    border-top-color: var(--color-accent-primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* ===== TOAST NOTIFICATIONS ===== */
.toast-container {
    position: fixed;
    top: 80px;
    left: 50%;
    transform: translateX(-50%);
    z-index: var(--z-toast);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    width: calc(100% - var(--spacing-lg) * 2);
    max-width: 400px;
    pointer-events: none;
}

.toast {
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--color-bg-card);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    animation: slideIn 0.3s ease;
    pointer-events: all;
}

.toast.success { border-left: 4px solid var(--color-success); }
.toast.error { border-left: 4px solid var(--color-error); }
.toast.warning { border-left: 4px solid var(--color-warning); }
.toast.info { border-left: 4px solid var(--color-info); }

@keyframes slideIn {
    from {
        transform: translateY(-100%);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* ===== RESPONSIVE ===== */
@media (min-width: 601px) {
    .app-container,
    .app-header,
    .bottom-nav {
        max-width: 600px;
    }
}

@media (max-width: 360px) {
    .nav-label {
        font-size: 10px;
    }

    .header-main-title {
        font-size: 18px;
    }
}

/* ===== UTILITIES ===== */
.hidden {
    display: none !important;
}

.fade-in {
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

button {
    -webkit-tap-highlight-color: transparent;
}

button:active {
    transform: scale(0.98);
}