/* ================================================
   QR Share System - Professional Dark Theme
   ================================================ */

@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;500;600&family=Plus+Jakarta+Sans:wght@400;500;600;700&display=swap');

:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #12121a;
    --bg-card: #1a1a24;
    --bg-card-hover: #22222e;
    --bg-input: #0d0d12;
    
    --border-color: #2a2a3a;
    --border-focus: #6366f1;
    
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --accent-primary: #6366f1;
    --accent-secondary: #818cf8;
    --accent-glow: rgba(99, 102, 241, 0.3);
    
    --success: #22c55e;
    --success-bg: rgba(34, 197, 94, 0.1);
    --warning: #f59e0b;
    --warning-bg: rgba(245, 158, 11, 0.1);
    --danger: #ef4444;
    --danger-bg: rgba(239, 68, 68, 0.1);
    
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 40px var(--accent-glow);
}

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

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.6;
}

/* Background Pattern */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: 
        radial-gradient(circle at 20% 20%, rgba(99, 102, 241, 0.08) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(129, 140, 248, 0.05) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

/* ================================================
   Layout Components
   ================================================ */

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

.page-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.main-content {
    flex: 1;
    padding: 2rem 0;
}

/* ================================================
   Header / Navigation
   ================================================ */

.header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 700;
    font-size: 1.25rem;
    color: var(--text-primary);
    text-decoration: none;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.user-badge {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: var(--bg-card);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.user-badge::before {
    content: '👤';
}

/* ================================================
   Cards
   ================================================ */

.card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    transition: all 0.2s ease;
}

.card:hover {
    background: var(--bg-card-hover);
}

.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1.5rem;
}

.card-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

/* ================================================
   Forms & Inputs
   ================================================ */

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

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.form-input {
    width: 100%;
    padding: 0.875rem 1rem;
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    transition: all 0.2s ease;
}

.form-input:focus {
    outline: none;
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.form-input::placeholder {
    color: var(--text-muted);
}

.form-input-code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.5rem;
    text-align: center;
    letter-spacing: 0.5em;
    text-transform: uppercase;
}

/* ================================================
   Buttons
   ================================================ */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.875rem 1.5rem;
    font-family: inherit;
    font-size: 0.9375rem;
    font-weight: 600;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
}

.btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    color: white;
    box-shadow: var(--shadow-sm), 0 0 20px var(--accent-glow);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md), 0 0 30px var(--accent-glow);
}

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

.btn-secondary:hover:not(:disabled) {
    background: var(--bg-card-hover);
    border-color: var(--accent-primary);
}

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

.btn-danger:hover:not(:disabled) {
    background: #dc2626;
}

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
    padding: 0.5rem;
}

.btn-ghost:hover {
    color: var(--text-primary);
    background: var(--bg-card);
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.8125rem;
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1rem;
}

.btn-block {
    width: 100%;
}

/* ================================================
   Login Page
   ================================================ */

.login-wrapper {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.login-card {
    width: 100%;
    max-width: 400px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: 2.5rem;
    box-shadow: var(--shadow-lg);
}

.login-header {
    text-align: center;
    margin-bottom: 2rem;
}

.login-logo {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    margin: 0 auto 1rem;
    box-shadow: var(--shadow-glow);
}

.login-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.login-subtitle {
    color: var(--text-secondary);
    font-size: 0.9375rem;
}

/* ================================================
   Dashboard
   ================================================ */

.dashboard-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.dashboard-title {
    font-size: 1.75rem;
    font-weight: 700;
}

.sessions-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.25rem;
}

.session-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1.25rem;
    transition: all 0.2s ease;
    cursor: pointer;
}

.session-card:hover {
    border-color: var(--accent-primary);
    box-shadow: var(--shadow-md);
}

.session-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    margin-bottom: 1rem;
}

.session-code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--accent-secondary);
    letter-spacing: 0.1em;
}

.session-status {
    display: inline-flex;
    align-items: center;
    gap: 0.375rem;
    padding: 0.25rem 0.75rem;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
}

.session-status.active {
    background: var(--success-bg);
    color: var(--success);
}

.session-status.active::before {
    content: '';
    width: 6px;
    height: 6px;
    background: var(--success);
    border-radius: 50%;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.session-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    font-size: 0.8125rem;
    color: var(--text-muted);
}

.session-meta-item {
    display: flex;
    align-items: center;
    gap: 0.375rem;
}

.session-timer {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 0.75rem;
    background: var(--warning-bg);
    border-radius: var(--radius-sm);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.875rem;
    color: var(--warning);
}

/* ================================================
   Session Detail / Upload Page
   ================================================ */

.session-detail-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.back-btn {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.2s ease;
}

.back-btn:hover {
    background: var(--bg-card-hover);
    color: var(--text-primary);
}

.session-info-bar {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    flex-wrap: wrap;
}

.session-code-display {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.session-code-display .code {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--accent-secondary);
    letter-spacing: 0.15em;
}

.upload-zone {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius-lg);
    padding: 3rem 2rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
    margin-bottom: 2rem;
}

.upload-zone:hover,
.upload-zone.drag-over {
    border-color: var(--accent-primary);
    background: rgba(99, 102, 241, 0.05);
}

.upload-zone-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.upload-zone-text {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.upload-zone-hint {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.upload-zone input[type="file"] {
    display: none;
}

/* ================================================
   Files Grid
   ================================================ */

.files-section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1rem;
}

.files-section-title {
    font-size: 1.125rem;
    font-weight: 600;
}

.files-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 1rem;
}

.file-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: all 0.2s ease;
}

.file-card:hover {
    border-color: var(--accent-primary);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.file-preview {
    aspect-ratio: 1;
    background: var(--bg-input);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.file-preview img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.file-info {
    padding: 0.75rem;
}

.file-name {
    font-size: 0.8125rem;
    font-weight: 500;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    margin-bottom: 0.25rem;
}

.file-timer {
    font-size: 0.75rem;
    color: var(--text-muted);
    font-family: 'JetBrains Mono', monospace;
}

.file-actions {
    display: flex;
    justify-content: flex-end;
    padding: 0 0.75rem 0.75rem;
    gap: 0.5rem;
}

/* ================================================
   Customer View
   ================================================ */

.customer-wrapper {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.customer-header {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.customer-header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.customer-session-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.customer-content {
    flex: 1;
    padding: 2rem 0;
}

.customer-code-entry {
    max-width: 480px;
    margin: 0 auto;
    padding: 2rem;
}

.code-entry-title {
    text-align: center;
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.code-entry-subtitle {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.customer-files {
    padding: 0 1rem;
}

.customer-files-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1.5rem;
    max-width: 1200px;
    margin: 0 auto;
}

.customer-file-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    overflow: hidden;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.customer-file-preview {
    aspect-ratio: 1;
    background: var(--bg-input);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
}

.customer-file-preview img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    padding: 1rem;
}

.customer-file-info {
    padding: 1rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

/* ================================================
   Modal / Lightbox
   ================================================ */

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    max-width: 90vw;
    max-height: 90vh;
}

.modal-content img {
    max-width: 100%;
    max-height: 90vh;
    border-radius: var(--radius-md);
}

.modal-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 48px;
    height: 48px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 50%;
    color: var(--text-primary);
    font-size: 1.5rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ================================================
   Empty State
   ================================================ */

.empty-state {
    text-align: center;
    padding: 4rem 2rem;
}

.empty-state-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.empty-state-text {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

/* ================================================
   Alerts & Notifications
   ================================================ */

.alert {
    padding: 1rem 1.25rem;
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.alert-error {
    background: var(--danger-bg);
    border: 1px solid var(--danger);
    color: var(--danger);
}

.alert-success {
    background: var(--success-bg);
    border: 1px solid var(--success);
    color: var(--success);
}

.alert-warning {
    background: var(--warning-bg);
    border: 1px solid var(--warning);
    color: var(--warning);
}

/* ================================================
   Loading Spinner
   ================================================ */

.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid var(--border-color);
    border-top-color: var(--accent-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

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

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(10, 10, 15, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

/* ================================================
   Create Session Modal
   ================================================ */

.modal-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 1rem;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.modal-backdrop.active {
    opacity: 1;
    visibility: visible;
}

.modal-box {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: 2rem;
    width: 100%;
    max-width: 420px;
    box-shadow: var(--shadow-lg);
    transform: scale(0.95);
    transition: transform 0.3s ease;
}

.modal-backdrop.active .modal-box {
    transform: scale(1);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1.5rem;
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 700;
}

/* ================================================
   Responsive Design
   ================================================ */

@media (max-width: 768px) {
    .header-inner {
        flex-wrap: wrap;
        gap: 1rem;
    }
    
    .dashboard-header {
        flex-direction: column;
        align-items: stretch;
    }
    
    .sessions-grid {
        grid-template-columns: 1fr;
    }
    
    .session-detail-header {
        flex-direction: column;
        align-items: stretch;
    }
    
    .session-info-bar {
        flex-direction: column;
        align-items: stretch;
    }
    
    .files-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .customer-files-grid {
        grid-template-columns: 1fr;
    }
    
    .login-card {
        padding: 1.5rem;
    }
    
    .upload-zone {
        padding: 2rem 1rem;
    }
}

@media (max-width: 480px) {
    .files-grid {
        grid-template-columns: 1fr;
    }
    
    .form-input-code {
        font-size: 1.25rem;
        letter-spacing: 0.3em;
    }
}

/* ================================================
   PWA Install Prompt
   ================================================ */

.pwa-prompt {
    position: fixed;
    bottom: 1rem;
    left: 1rem;
    right: 1rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    box-shadow: var(--shadow-lg);
    z-index: 1000;
    transform: translateY(150%);
    transition: transform 0.3s ease;
}

.pwa-prompt.show {
    transform: translateY(0);
}

.pwa-prompt-text {
    flex: 1;
}

.pwa-prompt-title {
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.pwa-prompt-subtitle {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

/* ================================================
   Connection Status
   ================================================ */

.connection-status {
    position: fixed;
    bottom: 1rem;
    right: 1rem;
    padding: 0.5rem 1rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.8125rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    z-index: 100;
}

.connection-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--success);
}

.connection-dot.disconnected {
    background: var(--danger);
}

/* ================================================
   Utility Classes
   ================================================ */

.text-center { text-align: center; }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--success); }
.text-danger { color: var(--danger); }
.text-warning { color: var(--warning); }

.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }

.hidden { display: none !important; }
.flex { display: flex; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }