:root {
    --bg-dark: #121212;
    --bg-panel: #1e1e1e;
    --bg-element: #2d2d2d;
    --border-color: #333333;
    --bg-hover: #3a3a3a;

    --text-main: #e0e0e0;
    --text-muted: #888888;

    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;

    --bg-preview: #f0f0f0;
    /* Default email client background */

    --font-sans: 'Inter', system-ui, sans-serif;
    --font-mono: 'Fira Code', monospace;
}

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

body {
    font-family: var(--font-sans);
    background-color: var(--bg-dark);
    color: var(--text-main);
    height: 100vh;
    overflow: hidden;
}

/* Utilities */
.text-primary {
    color: var(--primary);
}

.text-success {
    color: var(--success);
}

.text-warning {
    color: var(--warning);
}

.text-danger {
    color: var(--danger);
}

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

.w-full {
    width: 100%;
}

.hidden {
    display: none !important;
}

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

.mt-auto {
    margin-top: auto;
}

.text-xs {
    font-size: 0.75rem;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.6rem 1rem;
    border-radius: 6px;
    font-weight: 500;
    font-family: var(--font-sans);
    font-size: 0.85rem;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
}

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

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

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

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

.btn-outline {
    background: transparent;
    color: var(--text-muted);
    border: 1px solid var(--border-color);
}

.btn-outline:hover {
    background-color: var(--bg-element);
    color: var(--text-main);
}

/* Badges */
.badge {
    display: inline-block;
    padding: 0.15rem 0.4rem;
    border-radius: 4px;
    font-size: 0.7rem;
    font-weight: 700;
    font-family: var(--font-mono);
}

.badge-success {
    background: rgba(16, 185, 129, 0.15);
    color: var(--success);
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.badge-danger {
    background: rgba(239, 68, 68, 0.15);
    color: var(--danger);
    border: 1px solid rgba(239, 68, 68, 0.3);
}

/* Layout */
.app-layout {
    display: flex;
    height: 100vh;
    width: 100vw;
    overflow: hidden;
}

/* Sidebar */
.sidebar-controls {
    width: 320px;
    background-color: var(--bg-panel);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    padding: 1.5rem;
    overflow-y: auto;
    flex-shrink: 0;
}

.brand {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 2rem;
}

.brand h1 {
    font-size: 1.25rem;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.control-group {
    margin-bottom: 2rem;
}

.control-group h3 {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 0.75rem;
}

/* Code Editor in Sidebar */
.code-editor {
    width: 100%;
    height: 200px;
    background-color: #121212;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    color: #d4d4d4;
    font-family: var(--font-mono);
    font-size: 0.8rem;
    line-height: 1.4;
    padding: 0.75rem;
    resize: vertical;
    outline: none;
}

.code-editor:focus {
    border-color: var(--primary);
}

.output-editor {
    height: 100%;
    resize: none;
    border-radius: 0;
    border: none;
}

.status-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Toggles */
.toggle-control {
    display: flex;
    align-items: center;
    cursor: pointer;
    user-select: none;
    font-size: 0.85rem;
    color: var(--text-main);
    position: relative;
    gap: 0.5rem;
}

.toggle-control input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}

.toggle-bg {
    position: relative;
    display: inline-block;
    width: 36px;
    height: 20px;
    background-color: var(--bg-element);
    border-radius: 20px;
    transition: .3s;
    border: 1px solid var(--border-color);
}

.toggle-bg:before {
    position: absolute;
    content: "";
    height: 14px;
    width: 14px;
    left: 2px;
    bottom: 2px;
    background-color: var(--text-muted);
    border-radius: 50%;
    transition: .3s;
}

.toggle-control input:checked~.toggle-bg {
    background-color: var(--primary);
    border-color: var(--primary);
}

.toggle-control input:checked~.toggle-bg:before {
    transform: translateX(16px);
    background-color: white;
}

.info-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    border: 1px solid var(--text-muted);
    font-size: 0.6rem;
    color: var(--text-muted);
    font-weight: bold;
    cursor: help;
    margin-left: auto;
}

/* Device Width Toggles */
.device-toggles {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.btn-device {
    background: var(--bg-element);
    border: 1px solid var(--border-color);
    color: var(--text-muted);
    padding: 0.4rem 0.6rem;
    border-radius: 4px;
    font-size: 0.75rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-family: var(--font-sans);
    flex: 1;
    text-align: center;
    justify-content: center;
    transition: all 0.2s;
}

.btn-device:hover {
    background: var(--bg-hover);
    color: var(--text-main);
}

.btn-device.active {
    background: rgba(59, 130, 246, 0.1);
    border-color: var(--primary);
    color: var(--primary);
}

/* Main Preview Area */
.preview-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--bg-dark);
}

.preview-toolbar {
    height: 50px;
    background: var(--bg-panel);
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: center;
    padding: 0 1rem;
}

/* Tabs */
.tab-group {
    display: flex;
    height: 100%;
}

.tab {
    background: transparent;
    border: none;
    padding: 0 1.5rem;
    height: 100%;
    color: var(--text-muted);
    font-size: 0.85rem;
    font-weight: 500;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    font-family: var(--font-sans);
    transition: all 0.2s;
}

.tab:hover {
    color: white;
    background: rgba(255, 255, 255, 0.02);
}

.tab.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.preview-container-wrapper {
    flex: 1;
    position: relative;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    background: var(--bg-dark);
    background-image: radial-gradient(var(--border-color) 1px, transparent 1px);
    background-size: 20px 20px;
}

.preview-container {
    width: 100%;
    height: 100%;
    background: var(--bg-preview);
    box-shadow: 0 0 20px rgba(0, 0, 0, 0.5);
    transition: width 0.3s ease;
    /* For smooth resizing */
    position: relative;
    display: flex;
}

.email-frame {
    width: 100%;
    height: 100%;
    border: none;
    background: white;
}

/* Ruler for 600px guidance */
.ruler {
    position: absolute;
    pointer-events: none;
    z-index: 10;
    opacity: 0;
    transition: opacity 0.2s;
}

.preview-container-wrapper:hover .ruler {
    opacity: 1;
}

.ruler-x {
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 600px;
    height: 100%;
    border-left: 1px dashed rgba(239, 68, 68, 0.5);
    border-right: 1px dashed rgba(239, 68, 68, 0.5);
}

.ruler-x span {
    background: rgba(239, 68, 68, 0.8);
    color: white;
    font-size: 0.65rem;
    padding: 2px 6px;
    border-radius: 4px;
    position: absolute;
    top: 10px;
    right: -80px;
    font-family: var(--font-mono);
}


/* Custom Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}