:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f5;
    --bg-hover: #e8e8e8;
    --text-primary: #000000;
    --text-secondary: #666666;
    --border-color: #d0d0d0;
    --accent: #000000;
    --error: #dc3545;
    --success: #28a745;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #000000;
        --bg-secondary: #1a1a1a;
        --bg-hover: #2a2a2a;
        --text-primary: #ffffff;
        --text-secondary: #a0a0a0;
        --border-color: #333333;
        --accent: #ffffff;
    }
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Helvetica', 'Arial', sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
}

/* Login Page */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

.login-box {
    width: 100%;
    max-width: 360px;
}

.login-box h1 {
    font-size: 2rem;
    font-weight: 300;
    margin-bottom: 2rem;
    text-align: center;
    letter-spacing: 2px;
}

.login-box form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.login-box input {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.95rem;
    outline: none;
}

.login-box input:focus {
    border-color: var(--accent);
}

.login-box button {
    padding: 0.75rem;
    border: 1px solid var(--accent);
    background: var(--accent);
    color: var(--bg-primary);
    font-size: 0.95rem;
    cursor: pointer;
    transition: opacity 0.2s;
}

.login-box button:hover {
    opacity: 0.8;
}

.error {
    color: var(--error);
    font-size: 0.875rem;
    text-align: center;
    min-height: 1.25rem;
}

/* Main Application */
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding-bottom: 2rem;
    border-bottom: 1px solid var(--border-color);
    margin-bottom: 2rem;
}

header h1 {
    font-size: 1.5rem;
    font-weight: 300;
    letter-spacing: 2px;
}

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

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

.btn-text {
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    font-size: 0.95rem;
    padding: 0.5rem 0.75rem;
    transition: opacity 0.2s;
}

.btn-text:hover {
    opacity: 0.6;
}

/* Compose Area */
.compose-area {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

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

.field-group label {
    font-size: 0.875rem;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-secondary);
}

.field-group input,
.field-group textarea {
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.95rem;
    font-family: inherit;
    outline: none;
    resize: vertical;
}

.field-group input:focus,
.field-group textarea:focus {
    border-color: var(--accent);
}

/* Editor Header */
.editor-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.editor-controls {
    display: flex;
    gap: 1rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    color: var(--text-primary);
    text-transform: none;
    cursor: pointer;
}

.checkbox-label input[type="checkbox"] {
    cursor: pointer;
}

/* Format Toolbar */
.format-toolbar {
    display: flex;
    gap: 0.25rem;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    border-bottom: none;
    background: var(--bg-secondary);
    flex-wrap: wrap;
}

.format-toolbar.hidden {
    display: none;
}

.format-btn {
    padding: 0.5rem;
    border: 1px solid transparent;
    background: transparent;
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s;
}

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

.format-btn svg {
    width: 16px;
    height: 16px;
}

/* Attachments */
.attachments {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    min-height: 0;
}

.attachment-item {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 0.75rem;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    font-size: 0.875rem;
}

.attachment-remove {
    background: none;
    border: none;
    color: var(--text-primary);
    cursor: pointer;
    padding: 0;
    font-size: 1rem;
    line-height: 1;
}

.attachment-remove:hover {
    color: var(--error);
}

/* Buttons */
.actions {
    display: flex;
    gap: 1rem;
    padding-top: 1rem;
    align-items: center;
}

.send-group {
    display: flex;
    gap: 0;
    position: relative;
}

.btn-primary,
.btn-secondary {
    padding: 0.75rem 1.5rem;
    font-size: 0.95rem;
    cursor: pointer;
    border: 1px solid var(--accent);
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

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

.btn-primary:hover {
    opacity: 0.8;
}

.btn-secondary {
    background: transparent;
    color: var(--accent);
}

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

.btn-options {
    padding: 0.75rem;
    border: 1px solid var(--accent);
    border-left: none;
    background: var(--accent);
    color: var(--bg-primary);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity 0.2s;
}

.btn-options:hover {
    opacity: 0.8;
}

/* Send Options Menu */
.send-options-menu {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    z-index: 1000;
}

.send-options-menu.hidden {
    display: none;
}

.send-options-menu > .send-options-content {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    min-width: 300px;
    max-width: 400px;
    width: 100%;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

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

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

.options-group input {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid var(--border-color);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 0.9rem;
}

.send-options-menu button {
    width: 100%;
}

/* Status Messages */
.status {
    min-height: 1.5rem;
    font-size: 0.875rem;
}

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

.status.error {
    color: var(--error);
}

/* Command Palette */
.command-palette {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: flex-start;
    padding-top: 20vh;
    z-index: 1000;
}

.command-palette.hidden {
    display: none;
}

.command-palette-content {
    width: 90%;
    max-width: 500px;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
}

.command-palette input {
    width: 100%;
    padding: 1rem;
    border: none;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-primary);
    color: var(--text-primary);
    font-size: 1rem;
    outline: none;
}

.command-list {
    max-height: 300px;
    overflow-y: auto;
}

.command-item {
    padding: 0.75rem 1rem;
    cursor: pointer;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.command-item svg {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

.command-item:hover,
.command-item.selected {
    background: var(--bg-hover);
}

.command-item:last-child {
    border-bottom: none;
}

/* Modal */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    z-index: 1000;
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    padding: 2rem;
    max-width: 500px;
    width: 100%;
}

.modal-content h2 {
    font-size: 1.5rem;
    font-weight: 300;
    margin-bottom: 1.5rem;
}

.shortcuts-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.shortcut-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

kbd {
    padding: 0.25rem 0.5rem;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    font-family: monospace;
    font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 640px) {
    .container {
        padding: 1rem;
    }

    header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }

    .actions {
        flex-direction: column;
    }

    .btn-primary,
    .btn-secondary {
        width: 100%;
    }

    .delay-group {
        flex-direction: column;
        align-items: flex-start;
    }

    .delay-group input {
        width: 100%;
    }
}