/* --- CSS RESET & PROMĚNNÉ --- */
:root {
    --font-main: 'Plus Jakarta Sans', sans-serif;
    
    /* Dark Mode (Default) */
    --bg-gradient: linear-gradient(135deg, #0f111a 0%, #151926 100%);
    --panel-bg: rgba(26, 29, 46, 0.45);
    --panel-border: rgba(255, 255, 255, 0.07);
    --text-main: #f3f4f6;
    --text-muted: #9ca3af;
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --primary-glow: rgba(99, 102, 241, 0.3);
    --secondary: rgba(255, 255, 255, 0.08);
    --secondary-hover: rgba(255, 255, 255, 0.15);
    --input-bg: rgba(10, 11, 18, 0.5);
    --divider: rgba(255, 255, 255, 0.08);
    --toast-bg: rgba(20, 22, 36, 0.9);
    --shadow: 0 20px 40px rgba(0,0,0,0.3);
}

[data-theme="light"] {
    /* Light Mode */
    --bg-gradient: linear-gradient(135deg, #f0f4f8 0%, #e2e8f0 100%);
    --panel-bg: rgba(255, 255, 255, 0.65);
    --panel-border: rgba(0, 0, 0, 0.06);
    --text-main: #1e293b;
    --text-muted: #64748b;
    --primary: #4f46e5;
    --primary-hover: #3730a3;
    --primary-glow: rgba(79, 70, 229, 0.15);
    --secondary: rgba(0, 0, 0, 0.05);
    --secondary-hover: rgba(0, 0, 0, 0.1);
    --input-bg: rgba(255, 255, 255, 0.8);
    --divider: rgba(0, 0, 0, 0.06);
    --toast-bg: rgba(255, 255, 255, 0.95);
    --shadow: 0 20px 40px rgba(148, 163, 184, 0.15);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

body {
    font-family: var(--font-main);
    background: var(--bg-gradient);
    color: var(--text-main);
    min-height: 100vh;
    padding: 2rem;
    display: flex;
    justify-content: center;
    align-items: top;
    overflow-x: hidden;
}

.app-container {
    width: 100%;
    max-width: 1300px;
    margin: 0 auto;
}

/* Glassmorphism Panel */
.glass-panel {
    background: var(--panel-bg);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border: 1px solid var(--panel-border);
    border-radius: 24px;
    box-shadow: var(--shadow);
    padding: 2rem;
}

/* Header */
.main-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.2rem 2rem;
    margin-bottom: 2rem;
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    color: var(--primary);
    width: 32px;
    height: 32px;
}

.logo-area h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.5px;
}

.logo-area h1 span {
    color: var(--primary);
}

/* Grid Layout */
.main-grid {
    display: grid;
    grid-template-columns: 1.4fr 1fr;
    gap: 2rem;
    align-items: start;
}

.right-column {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.section-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* --- TABS (TYPY QR) --- */
.tabs-container {
    display: flex;
    gap: 0.5rem;
    overflow-x: auto;
    padding-bottom: 0.75rem;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid var(--divider);
}

.custom-scrollbar::-webkit-scrollbar {
    height: 5px;
    width: 5px;
}
.custom-scrollbar::-webkit-scrollbar-track {
    background: transparent;
}
.custom-scrollbar::-webkit-scrollbar-thumb {
    background: var(--divider);
    border-radius: 10px;
}

.tab-btn {
    background: transparent;
    border: 1px solid transparent;
    color: var(--text-muted);
    padding: 0.6rem 1rem;
    border-radius: 12px;
    cursor: pointer;
    font-weight: 500;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    white-space: nowrap;
    transition: all 0.2s ease;
}

.tab-btn:hover {
    color: var(--text-main);
    background: var(--secondary);
}

.tab-btn.active {
    color: #ffffff;
    background: var(--primary);
    box-shadow: 0 4px 12px var(--primary-glow);
}

/* --- FORMULÁŘE --- */
.form-group {
    display: none;
    animation: fadeIn 0.3s ease forwards;
}

.form-group.active {
    display: block;
}

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

input[type="text"],
input[type="url"],
input[type="tel"],
input[type="email"],
input[type="password"],
textarea,
select {
    width: 100%;
    background: var(--input-bg);
    border: 1px solid var(--panel-border);
    padding: 0.8rem 1rem;
    border-radius: 12px;
    color: var(--text-main);
    font-family: var(--font-main);
    font-size: 0.95rem;
    outline: none;
    transition: all 0.2s ease;
}

input:focus, textarea:focus, select:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-glow);
}

textarea {
    resize: vertical;
    min-height: 100px;
}

.grid-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

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

.divider {
    border: none;
    border-top: 1px solid var(--divider);
    margin: 1.5rem 0;
}

/* --- DESIGN CONFIG --- */
.presets-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.preset-btn {
    background: var(--secondary);
    border: 1px solid var(--panel-border);
    color: var(--text-main);
    padding: 0.5rem;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: 500;
    transition: all 0.2s;
}

.preset-btn.active, .preset-btn:hover {
    border-color: var(--primary);
    background: var(--secondary-hover);
}

.color-picker-wrapper {
    display: flex;
    gap: 0.5rem;
}

input[type="color"] {
    -webkit-appearance: none;
    border: none;
    width: 40px;
    height: 40px;
    border-radius: 10px;
    cursor: pointer;
    background: transparent;
}

input[type="color"]::-webkit-color-swatch-wrapper { padding: 0; }
input[type="color"]::-webkit-color-swatch {
    border: 1px solid var(--panel-border);
    border-radius: 10px;
}

/* Drag & Drop Zone */
.drop-zone {
    border: 2px dashed var(--panel-border);
    border-radius: 16px;
    padding: 1.5rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s ease;
    background: rgba(0,0,0,0.05);
}

.drop-zone.drag-over {
    border-color: var(--primary);
    background: var(--primary-glow);
}

.drop-icon {
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

.drop-zone p {
    font-size: 0.85rem;
    color: var(--text-muted);
}

.drop-zone p span {
    color: var(--primary);
    font-weight: 600;
}

.logo-preview-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--secondary);
    padding: 0.5rem 1rem;
    border-radius: 10px;
    margin-top: 0.5rem;
    font-size: 0.85rem;
}

.text-danger-btn {
    background: transparent;
    border: none;
    color: #ef4444;
    cursor: pointer;
}

/* --- PREVIEW PANEL & QR DISPLAY --- */
.preview-panel {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.preview-panel .section-title {
    align-self: flex-start;
}

.qr-display-container {
    position: relative;
    background: #ffffff;
    padding: 1.5rem;
    border-radius: 20px;
    box-shadow: inset 0 0 20px rgba(0,0,0,0.05);
    margin-bottom: 2rem;
    display: inline-flex;
    justify-content: center;
    align-items: center;
    min-width: 260px;
    min-height: 260px;
}

#qr-canvas-target canvas {
    max-width: 100% !important;
    height: auto !important;
    display: block;
}

/* Loader */
.qr-loader {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(255,255,255,0.8);
    backdrop-filter: blur(4px);
    border-radius: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 10;
}

.spinner {
    width: 40px;
    height: 40px;
    border: 4px solid rgba(99, 102, 241, 0.2);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

/* Tlačítka akcí */
.action-buttons-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 0.75rem;
    width: 100%;
}

.btn {
    font-family: var(--font-main);
    padding: 0.8rem 1rem;
    border-radius: 12px;
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    border: none;
    transition: all 0.2s ease;
}

.btn-primary {
    background: var(--primary);
    color: #ffffff;
    grid-column: span 2;
    box-shadow: 0 4px 14px var(--primary-glow);
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

.btn-secondary {
    background: var(--secondary);
    color: var(--text-main);
    border: 1px solid var(--panel-border);
}

.btn-secondary:hover {
    background: var(--secondary-hover);
}

.icon-btn {
    background: var(--secondary);
    border: 1px solid var(--panel-border);
    color: var(--text-main);
    padding: 0.6rem;
    border-radius: 12px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}

.icon-btn:hover { background: var(--secondary-hover); }

/* --- HISTORIE --- */
.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.text-btn {
    background: transparent;
    border: none;
    color: var(--primary);
    cursor: pointer;
    font-weight: 500;
    font-size: 0.85rem;
}

.history-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    max-height: 200px;
    overflow-y: auto;
    padding-right: 0.5rem;
}

.history-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--secondary);
    padding: 0.75rem 1rem;
    border-radius: 12px;
    font-size: 0.85rem;
}

.history-item-info {
    display: flex;
    flex-direction: column;
}

.history-type {
    font-weight: 600;
    text-transform: uppercase;
    font-size: 0.7rem;
    color: var(--primary);
}

.history-value {
    max-width: 180px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-muted);
}

.empty-history {
    text-align: center;
    color: var(--text-muted);
    font-size: 0.85rem;
    padding: 1rem;
}

/* --- TOAST NOTIFIKACE --- */
.toast-container {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    z-index: 1000;
}

.toast {
    background: var(--toast-bg);
    border: 1px solid var(--panel-border);
    backdrop-filter: blur(12px);
    color: var(--text-main);
    padding: 1rem 1.5rem;
    border-radius: 14px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    animation: slideIn 0.3s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

/* --- ANIMACE --- */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(5px); }
    to { opacity: 1; transform: translateY(0); }
}

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

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

.hidden { display: none !important; }

/* --- RESPONSIVITA --- */
@media (max-width: 968px) {
    body { padding: 1rem; }
    .main-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .presets-grid { grid-template-columns: repeat(2, 1fr); }
    .action-buttons-grid { grid-template-columns: 1fr; }
    .btn-primary { grid-column: span 1; }
}