/**
 * Airbnb Layout System - Purple Brand
 * Reusable components and layouts for all frontend pages
 * Author: Claude Code
 * Date: 2025
 */

/* ============================================
   CSS VARIABLES - AIRBNB STYLE WITH PURPLE
   ============================================ */
:root {
    /* Purple Brand Colors */
    --brand-purple: #667eea;
    --brand-purple-dark: #5568d3;
    --brand-purple-light: #7c8ff0;
    --brand-purple-ultra-light: #e8ebfa;
    --brand-violet: #764ba2;

    /* Airbnb Neutral Colors */
    --color-white: #ffffff;
    --color-black: #000000;
    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;

    /* Airbnb Accent Colors */
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-error: #ef4444;
    --color-info: #3b82f6;

    /* Typography */
    --font-family-primary: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;

    /* Spacing (Airbnb 4px base) */
    --space-1: 0.25rem;   /* 4px */
    --space-2: 0.5rem;    /* 8px */
    --space-3: 0.75rem;   /* 12px */
    --space-4: 1rem;      /* 16px */
    --space-5: 1.25rem;   /* 20px */
    --space-6: 1.5rem;    /* 24px */
    --space-8: 2rem;      /* 32px */
    --space-10: 2.5rem;   /* 40px */
    --space-12: 3rem;     /* 48px */
    --space-16: 4rem;     /* 64px */
    --space-20: 5rem;     /* 80px */
    --space-24: 6rem;     /* 96px */

    /* Border Radius */
    --radius-sm: 0.375rem;   /* 6px */
    --radius-md: 0.5rem;     /* 8px */
    --radius-lg: 0.75rem;    /* 12px */
    --radius-xl: 1rem;       /* 16px */
    --radius-2xl: 1.5rem;    /* 24px */
    --radius-full: 9999px;

    /* Shadows (Airbnb style) */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.15);
    --shadow-2xl: 0 25px 50px rgba(0, 0, 0, 0.25);

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

    /* Z-Index Scale */
    --z-dropdown: 1000;
    --z-sticky: 1020;
    --z-fixed: 1030;
    --z-modal-backdrop: 1040;
    --z-modal: 1050;
    --z-popover: 1060;
    --z-tooltip: 1070;
}

/* ============================================
   GLOBAL RESETS & BASE STYLES
   ============================================ */
* {
    box-sizing: border-box;
}

body {
    font-family: var(--font-family-primary);
    color: var(--color-gray-900);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ============================================
   PAGE WRAPPER & MAIN CONTENT
   ============================================ */
.page-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

#main-content {
    flex: 1;
}

/* ============================================
   CONTAINERS (Airbnb max-width approach)
   ============================================ */
.container-airbnb {
    width: 100%;
    max-width: 1280px;
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--space-6);
    padding-right: var(--space-6);
}

.container-airbnb-wide {
    width: 100%;
    max-width: 1440px;
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--space-6);
    padding-right: var(--space-6);
}

.container-airbnb-narrow {
    width: 100%;
    max-width: 960px;
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--space-6);
    padding-right: var(--space-6);
}

@media (min-width: 1440px) {
    .container-airbnb {
        max-width: 1320px;
    }
}

@media (max-width: 768px) {
    .container-airbnb,
    .container-airbnb-wide,
    .container-airbnb-narrow {
        padding-left: var(--space-4);
        padding-right: var(--space-4);
    }
}

/* ============================================
   BREADCRUMBS (Airbnb style)
   ============================================ */
.breadcrumb-airbnb {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-4) 0;
    list-style: none;
    margin: 0;
    font-size: 14px;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.breadcrumb-item a {
    color: var(--color-gray-600);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.breadcrumb-item a:hover {
    color: var(--brand-purple);
    text-decoration: underline;
}

.breadcrumb-item.active {
    color: var(--color-gray-900);
    font-weight: var(--font-weight-medium);
}

.breadcrumb-separator {
    color: var(--color-gray-400);
    font-size: 12px;
}

/* ============================================
   PAGE HEADERS (Airbnb style)
   ============================================ */
.page-header-airbnb {
    padding: var(--space-12) 0 var(--space-8);
    background: linear-gradient(135deg,
        rgba(102, 126, 234, 0.03) 0%,
        rgba(118, 75, 162, 0.03) 100%);
    border-bottom: 1px solid var(--color-gray-200);
}

.page-header-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.page-title {
    font-size: clamp(28px, 5vw, 42px);
    font-weight: var(--font-weight-bold);
    color: var(--color-gray-900);
    margin-bottom: var(--space-4);
    line-height: 1.2;
}

.page-subtitle {
    font-size: clamp(16px, 3vw, 18px);
    color: var(--color-gray-600);
    line-height: 1.6;
    margin-bottom: 0;
}

/* Compact page header */
.page-header-compact {
    padding: var(--space-8) 0 var(--space-6);
}

.page-header-compact .page-title {
    font-size: clamp(24px, 4vw, 32px);
    margin-bottom: var(--space-2);
}

/* ============================================
   SECTION WRAPPERS
   ============================================ */
.section-airbnb {
    padding: var(--space-16) 0;
}

.section-airbnb-sm {
    padding: var(--space-12) 0;
}

.section-airbnb-lg {
    padding: var(--space-20) 0;
}

.section-gray {
    background: var(--color-gray-50);
}

.section-white {
    background: var(--color-white);
}

.section-purple-light {
    background: linear-gradient(135deg,
        rgba(102, 126, 234, 0.05) 0%,
        rgba(118, 75, 162, 0.05) 100%);
}

@media (max-width: 768px) {
    .section-airbnb {
        padding: var(--space-12) 0;
    }

    .section-airbnb-sm {
        padding: var(--space-8) 0;
    }

    .section-airbnb-lg {
        padding: var(--space-16) 0;
    }
}

/* ============================================
   SECTION HEADERS (Reusable)
   ============================================ */
.section-header-airbnb {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    margin-bottom: var(--space-12);
    gap: var(--space-6);
}

.section-header-center {
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.section-header-left h2,
.section-header-center h2 {
    font-size: clamp(24px, 4vw, 36px);
    font-weight: var(--font-weight-bold);
    color: var(--color-gray-900);
    margin-bottom: var(--space-2);
    line-height: 1.2;
}

.section-header-left p,
.section-header-center p {
    font-size: clamp(14px, 2vw, 16px);
    color: var(--color-gray-600);
    line-height: 1.6;
    margin: 0;
}

.section-header-right {
    flex-shrink: 0;
}

.view-all-link-airbnb {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    color: var(--brand-purple);
    font-weight: var(--font-weight-semibold);
    font-size: 14px;
    border: 2px solid var(--brand-purple);
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
    text-decoration: none;
}

.view-all-link-airbnb:hover {
    background: var(--brand-purple);
    color: var(--color-white);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

@media (max-width: 768px) {
    .section-header-airbnb {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-4);
    }

    .section-header-right {
        width: 100%;
    }

    .view-all-link-airbnb {
        width: 100%;
        justify-content: center;
    }
}

/* ============================================
   GRID LAYOUTS (Airbnb responsive)
   ============================================ */
.grid-airbnb {
    display: grid;
    gap: var(--space-6);
}

.grid-airbnb-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-airbnb-3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid-airbnb-4 {
    grid-template-columns: repeat(4, 1fr);
}

/* Auto-fit grids (Airbnb responsive approach) */
.grid-auto-fit {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

.grid-auto-fit-sm {
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.grid-auto-fit-lg {
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
}

@media (max-width: 991px) {
    .grid-airbnb-3,
    .grid-airbnb-4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 576px) {
    .grid-airbnb-2,
    .grid-airbnb-3,
    .grid-airbnb-4 {
        grid-template-columns: 1fr;
    }
}

/* ============================================
   CARDS (Airbnb style)
   ============================================ */
.card-airbnb {
    background: var(--color-white);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-xl);
    overflow: hidden;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.card-airbnb:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: var(--color-gray-300);
}

.card-header {
    padding: var(--space-5);
    border-bottom: 1px solid var(--color-gray-200);
}

.card-body {
    padding: var(--space-6);
}

.card-footer {
    padding: var(--space-5);
    background: var(--color-gray-50);
    border-top: 1px solid var(--color-gray-200);
}

/* ============================================
   BUTTONS (Airbnb style)
   ============================================ */
.btn-airbnb {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: 14px 24px;
    font-size: 16px;
    font-weight: var(--font-weight-semibold);
    border-radius: var(--radius-lg);
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    line-height: 1.5;
}

.btn-airbnb-primary {
    background: linear-gradient(135deg, var(--brand-purple) 0%, var(--brand-violet) 100%);
    color: var(--color-white);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.btn-airbnb-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.4);
    color: var(--color-white);
}

.btn-airbnb-secondary {
    background: var(--color-white);
    color: var(--color-gray-900);
    border: 2px solid var(--color-gray-300);
}

.btn-airbnb-secondary:hover {
    border-color: var(--brand-purple);
    color: var(--brand-purple);
    background: var(--color-gray-50);
}

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

.btn-airbnb-outline:hover {
    background: var(--brand-purple);
    color: var(--color-white);
}

.btn-airbnb-sm {
    padding: 10px 20px;
    font-size: 14px;
}

.btn-airbnb-lg {
    padding: 16px 32px;
    font-size: 18px;
}

.btn-airbnb-block {
    width: 100%;
}

/* ============================================
   BADGES & TAGS
   ============================================ */
.badge-airbnb {
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    padding: 4px 12px;
    font-size: 12px;
    font-weight: var(--font-weight-semibold);
    border-radius: var(--radius-full);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.badge-primary {
    background: rgba(102, 126, 234, 0.1);
    color: var(--brand-purple);
}

.badge-success {
    background: rgba(16, 185, 129, 0.1);
    color: var(--color-success);
}

.badge-warning {
    background: rgba(245, 158, 11, 0.1);
    color: var(--color-warning);
}

.badge-error {
    background: rgba(239, 68, 68, 0.1);
    color: var(--color-error);
}

/* ============================================
   LOADING STATES
   ============================================ */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(4px);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: var(--z-modal);
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--color-gray-200);
    border-top-color: var(--brand-purple);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.skeleton-loading {
    background: linear-gradient(
        90deg,
        var(--color-gray-200) 0%,
        var(--color-gray-300) 50%,
        var(--color-gray-200) 100%
    );
    background-size: 200% 100%;
    animation: shimmer 1.5s ease-in-out infinite;
    border-radius: var(--radius-md);
}

@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}

/* ============================================
   EMPTY STATES
   ============================================ */
.empty-state-airbnb {
    text-align: center;
    padding: var(--space-20) var(--space-6);
}

.empty-state-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto var(--space-6);
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-gray-100);
    border-radius: var(--radius-full);
    color: var(--color-gray-400);
    font-size: 36px;
}

.empty-state-title {
    font-size: 24px;
    font-weight: var(--font-weight-bold);
    color: var(--color-gray-900);
    margin-bottom: var(--space-3);
}

.empty-state-description {
    font-size: 16px;
    color: var(--color-gray-600);
    line-height: 1.6;
    margin-bottom: var(--space-6);
}

/* ============================================
   DIVIDERS
   ============================================ */
.divider-airbnb {
    height: 1px;
    background: var(--color-gray-200);
    margin: var(--space-8) 0;
}

.divider-thick {
    height: 2px;
    background: var(--color-gray-300);
}

.divider-gradient {
    height: 1px;
    background: linear-gradient(
        90deg,
        transparent 0%,
        var(--brand-purple) 50%,
        transparent 100%
    );
}

/* ============================================
   ALERTS & NOTIFICATIONS
   ============================================ */
.alert-airbnb {
    padding: var(--space-4) var(--space-5);
    border-radius: var(--radius-lg);
    border-left: 4px solid;
    display: flex;
    align-items: flex-start;
    gap: var(--space-3);
}

.alert-success {
    background: rgba(16, 185, 129, 0.1);
    border-left-color: var(--color-success);
    color: var(--color-gray-900);
}

.alert-warning {
    background: rgba(245, 158, 11, 0.1);
    border-left-color: var(--color-warning);
    color: var(--color-gray-900);
}

.alert-error {
    background: rgba(239, 68, 68, 0.1);
    border-left-color: var(--color-error);
    color: var(--color-gray-900);
}

.alert-info {
    background: rgba(59, 130, 246, 0.1);
    border-left-color: var(--color-info);
    color: var(--color-gray-900);
}

/* ============================================
   UTILITY CLASSES
   ============================================ */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mt-0 { margin-top: 0; }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-12 { margin-top: var(--space-12); }

.mb-0 { margin-bottom: 0; }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }
.mb-12 { margin-bottom: var(--space-12); }

.hidden { display: none !important; }
.visible { display: block !important; }

@media (max-width: 768px) {
    .hidden-mobile { display: none !important; }
}

@media (min-width: 769px) {
    .hidden-desktop { display: none !important; }
}

/* ============================================
   PRINT STYLES
   ============================================ */
@media print {
    .page-header-airbnb,
    .breadcrumb-airbnb,
    .loading-overlay,
    .btn-airbnb {
        display: none !important;
    }

    .section-airbnb {
        padding: var(--space-6) 0;
    }
}