:root {
    --bg-color: #f4f4f5;
    --body-bg: #ffffff;
    --primary-color: #3b82f6;
    --text-color: #1f2937;
    --border-color: #e5e7eb;
    --hover-bg: #f3f4f6;
    --danger-color: #ef4444;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: #f9fafb;
    color: var(--text-color);
    height: 100vh;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

button {
    cursor: pointer;
    font-family: inherit;
}

.btn {
    padding: 0.5rem 1rem;
    border-radius: 4px;
    border: none;
    font-weight: 500;
    transition: opacity 0.2s;
}

.btn:hover {
    opacity: 0.9;
}

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

.btn.secondary {
    background-color: #e5e7eb;
    color: #374151;
}

.btn.danger {
    background-color: #fee2e2;
    color: var(--danger-color);
}

.icon-btn {
    background: none;
    border: none;
    font-size: 1.25rem;
    padding: 0.25rem;
    color: #6b7280;
    border-radius: 4px;
}

.icon-btn:hover {
    background-color: var(--hover-bg);
    color: #374151;
}

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

.full-width {
    width: 100%;
}

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

/* Header */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 1.5rem;
    background-color: white;
    border-bottom: 1px solid var(--border-color);
    z-index: 10;
}

.app-header h1 {
    font-size: 1.25rem;
    font-weight: 600;
}

.header-center {
    display: flex;
    gap: 0.5rem;
}

.device-toggle {
    background: none;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 0.25rem 0.5rem;
    font-size: 1rem;
    opacity: 0.5;
}

.device-toggle.active {
    opacity: 1;
    background-color: var(--hover-bg);
    border-color: #d1d5db;
}

.header-right {
    display: flex;
    gap: 0.75rem;
    align-items: center;
}

/* Main Container */
.app-container {
    display: flex;
    flex: 1;
    overflow: hidden;
}

/* Sidebar (Left) */
.sidebar {
    width: 260px;
    background-color: white;
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    overflow-y: auto;
}

.sidebar-section {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.sidebar-section h3 {
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: #4b5563;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.hint {
    font-weight: 400;
    font-size: 0.75rem;
    color: #9ca3af;
}

.form-select {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background-color: white;
    font-family: inherit;
}

.color-picker-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.color-picker-group label {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.875rem;
    color: #374151;
}

.color-picker-group input[type="color"] {
    width: 32px;
    height: 32px;
    border: none;
    border-radius: 4px;
    padding: 0;
    cursor: pointer;
}

/* Draggable Palette Blocks */
.blocks-palette {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
}

.palette-block {
    background-color: var(--hover-bg);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 0.75rem 0.5rem;
    text-align: center;
    font-size: 0.875rem;
    font-weight: 500;
    color: #4b5563;
    cursor: grab;
    user-select: none;
}

.palette-block:active {
    cursor: grabbing;
}

/* Canvas Area */
.canvas-area {
    flex: 1;
    background-color: #e5e7eb;
    display: flex;
    justify-content: center;
    padding: 2rem;
    overflow-y: auto;
}

#preview-wrapper {
    transition: width 0.3s;
    height: max-content;
    min-height: 100%;
    width: 100%;
}

#preview-wrapper.preview-desktop {
    width: 600px;
}

#preview-wrapper.preview-mobile {
    width: 375px;
}

.email-canvas {
    background-color: var(--bg-color);
    min-height: 500px;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    position: relative;
    /* transition: background-color 0.2s; */
}

.email-canvas.drag-over {
    box-shadow: 0 0 0 3px var(--primary-color) inset;
}

.empty-state {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: #9ca3af;
    font-size: 0.875rem;
    text-align: center;
    pointer-events: none;
}

/* Email Blocks (in Canvas) */
.email-block {
    position: relative;
    border: 2px dashed transparent;
    cursor: pointer;
    margin-bottom: 1rem;
    transition: border-color 0.2s;
}

.email-block:hover {
    border-color: #d1d5db;
}

.email-block.selected {
    border-color: var(--primary-color);
}

.email-block-content {
    background-color: var(--body-bg);
    padding: 1.5rem;
    color: var(--text-color);
}

.email-block-content.header-block { font-size: 24px; font-weight: bold; text-align: center; }
.email-block-content.text-block { font-size: 16px; line-height: 1.5; }
.email-block-content.image-block { text-align: center; }
.email-block-content.image-block img { max-width: 100%; height: auto; display: block; margin: 0 auto; background: #e5e7eb; min-height: 100px; }
.email-block-content.button-block { text-align: center; }
.email-block-content.button-block a { display: inline-block; padding: 12px 24px; background-color: var(--primary-color); color: white; text-decoration: none; border-radius: 4px; font-weight: bold; }
.email-block-content.divider-block { padding: 1rem 0; border-bottom: 1px solid var(--border-color); }
.email-block-content.spacer-block { height: 30px; padding: 0; background: transparent; }

/* Properties Panel (Right) */
.properties-panel {
    width: 250px;
    background-color: white;
    border-left: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    transform: translateX(100%);
    display: none;
}

.properties-panel.open {
    transform: translateX(0);
    display: flex;
}

.properties-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.properties-header h3 {
    font-size: 0.875rem;
    font-weight: 600;
}

.properties-content {
    padding: 1rem;
    flex: 1;
    overflow-y: auto;
}

.empty-props {
    color: #9ca3af;
    font-size: 0.875rem;
    text-align: center;
}

.prop-group {
    margin-bottom: 1rem;
}

.prop-group label {
    display: block;
    font-size: 0.75rem;
    font-weight: 600;
    color: #4b5563;
    margin-bottom: 0.25rem;
    text-transform: uppercase;
}

.prop-input {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-family: inherit;
    font-size: 0.875rem;
}
textarea.prop-input {
    resize: vertical;
    min-height: 60px;
}

.block-actions {
    padding: 1rem;
    border-top: 1px solid var(--border-color);
}
.hidden { display: none !important; }

/* Toast */
.toast {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    background-color: #10b981;
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    font-weight: 500;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transform: translateY(100px);
    opacity: 0;
    transition: all 0.3s ease;
    z-index: 50;
}
.toast.show {
    transform: translateY(0);
    opacity: 1;
}