/* ===== CSS Variables / Theming ===== */
:root {
    --font-mono: 'Cascadia Code', 'Fira Code', 'Consolas', 'Monaco', 'Courier New', monospace;
    --font-ui: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --transition-speed: 0.2s;
}

.theme-dark {
    --bg-primary: #1e1e2e;
    --bg-secondary: #181825;
    --bg-tertiary: #313244;
    --bg-hover: #45475a;
    --bg-active: #585b70;
    --bg-editor: #11111b;
    --bg-highlight: rgba(249, 226, 175, 0.12);
    --bg-find-match: rgba(249, 226, 175, 0.25);
    --bg-find-current: rgba(166, 227, 161, 0.4);
    --text-primary: #cdd6f4;
    --text-secondary: #a6adc8;
    --text-muted: #6c7086;
    --text-accent: #89b4fa;
    --border-color: #313244;
    --border-active: #89b4fa;
    --tab-active-bg: #11111b;
    --tab-bg: #1e1e2e;
    --tab-hover-bg: #313244;
    --scrollbar-thumb: #45475a;
    --scrollbar-track: #1e1e2e;
    --btn-hover: #45475a;
    --selection: rgba(137, 180, 250, 0.3);
    /* Syntax colors */
    --syn-keyword: #cba6f7;
    --syn-string: #a6e3a1;
    --syn-comment: #6c7086;
    --syn-number: #fab387;
    --syn-function: #89b4fa;
    --syn-operator: #89dceb;
    --syn-tag: #f38ba8;
    --syn-attribute: #f9e2af;
    --syn-type: #f9e2af;
    --syn-property: #89b4fa;
    --syn-punctuation: #9399b2;
    --syn-regex: #f38ba8;
    --syn-constant: #fab387;
}

.theme-light {
    --bg-primary: #eff1f5;
    --bg-secondary: #e6e9ef;
    --bg-tertiary: #ccd0da;
    --bg-hover: #bcc0cc;
    --bg-active: #acb0be;
    --bg-editor: #ffffff;
    --bg-highlight: rgba(223, 142, 29, 0.1);
    --bg-find-match: rgba(223, 142, 29, 0.25);
    --bg-find-current: rgba(64, 160, 43, 0.3);
    --text-primary: #4c4f69;
    --text-secondary: #5c5f77;
    --text-muted: #9ca0b0;
    --text-accent: #1e66f5;
    --border-color: #ccd0da;
    --border-active: #1e66f5;
    --tab-active-bg: #ffffff;
    --tab-bg: #eff1f5;
    --tab-hover-bg: #ccd0da;
    --scrollbar-thumb: #bcc0cc;
    --scrollbar-track: #eff1f5;
    --btn-hover: #ccd0da;
    --selection: rgba(30, 102, 245, 0.2);
    /* Syntax colors */
    --syn-keyword: #8839ef;
    --syn-string: #40a02b;
    --syn-comment: #9ca0b0;
    --syn-number: #fe640b;
    --syn-function: #1e66f5;
    --syn-operator: #04a5e5;
    --syn-tag: #d20f39;
    --syn-attribute: #df8e1d;
    --syn-type: #df8e1d;
    --syn-property: #1e66f5;
    --syn-punctuation: #6c6f85;
    --syn-regex: #d20f39;
    --syn-constant: #fe640b;
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: var(--font-ui);
    background: var(--bg-primary);
    color: var(--text-primary);
    display: flex;
    flex-direction: column;
    transition: background var(--transition-speed), color var(--transition-speed);
}

::selection {
    background: var(--selection);
}

/* ===== Scrollbar ===== */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
}

::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: 5px;
}

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

/* ===== Toolbar ===== */
.toolbar {
    display: flex;
    align-items: center;
    gap: 2px;
    padding: 4px 8px;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
    user-select: none;
}

.toolbar-group {
    display: flex;
    align-items: center;
    gap: 2px;
}

.toolbar-separator {
    width: 1px;
    height: 24px;
    background: var(--border-color);
    margin: 0 6px;
}

.toolbar-spacer {
    flex: 1;
}

.toolbar button {
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 5px 10px;
    border: none;
    border-radius: 4px;
    background: transparent;
    color: var(--text-secondary);
    font-family: var(--font-ui);
    font-size: 12px;
    cursor: pointer;
    transition: background var(--transition-speed), color var(--transition-speed);
    white-space: nowrap;
}

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

.toolbar button svg {
    width: 16px;
    height: 16px;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    fill: none;
    flex-shrink: 0;
}

#btn-theme .icon-moon {
    display: none;
}

.theme-light #btn-theme .icon-sun {
    display: none;
}

.theme-light #btn-theme .icon-moon {
    display: block;
}

/* ===== Tab Bar ===== */
.tab-bar {
    display: flex;
    align-items: stretch;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    flex-shrink: 0;
    overflow-x: auto;
    overflow-y: hidden;
    user-select: none;
}

.tab-bar::-webkit-scrollbar {
    height: 3px;
}

.tabs-container {
    display: flex;
    align-items: stretch;
    min-width: 0;
}

.tab {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    background: var(--tab-bg);
    border-right: 1px solid var(--border-color);
    color: var(--text-muted);
    font-size: 12px;
    cursor: pointer;
    white-space: nowrap;
    max-width: 180px;
    min-width: 80px;
    position: relative;
    transition: background var(--transition-speed), color var(--transition-speed);
}

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

.tab.active {
    background: var(--tab-active-bg);
    color: var(--text-primary);
    border-bottom: 2px solid var(--border-active);
}

.tab-name {
    overflow: hidden;
    text-overflow: ellipsis;
    flex: 1;
}

.tab-name[contenteditable="true"] {
    outline: none;
    border-bottom: 1px solid var(--text-accent);
    min-width: 40px;
}

.tab-modified {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--text-accent);
    flex-shrink: 0;
    display: none;
}

.tab.modified .tab-modified {
    display: block;
}

.tab-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 18px;
    height: 18px;
    border: none;
    border-radius: 3px;
    background: transparent;
    color: var(--text-muted);
    font-size: 14px;
    line-height: 1;
    cursor: pointer;
    flex-shrink: 0;
    opacity: 0;
    transition: opacity 0.15s, background 0.15s;
}

.tab:hover .tab-close,
.tab.active .tab-close {
    opacity: 1;
}

.tab-close:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.tab-add {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    border: none;
    background: transparent;
    color: var(--text-muted);
    font-size: 18px;
    cursor: pointer;
    flex-shrink: 0;
    transition: background var(--transition-speed), color var(--transition-speed);
}

.tab-add:hover {
    background: var(--tab-hover-bg);
    color: var(--text-primary);
}

/* ===== Find/Replace Panel ===== */
.find-panel {
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    padding: 6px 12px;
    flex-shrink: 0;
}

.find-row, .replace-row {
    display: flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 4px;
}

.replace-row {
    margin-bottom: 0;
}

.find-panel input[type="text"] {
    flex: 1;
    max-width: 320px;
    padding: 4px 8px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    background: var(--bg-editor);
    color: var(--text-primary);
    font-family: var(--font-mono);
    font-size: 13px;
    outline: none;
    transition: border-color var(--transition-speed);
}

.find-panel input[type="text"]:focus {
    border-color: var(--border-active);
}

.find-option {
    display: flex;
    align-items: center;
    gap: 3px;
    font-size: 12px;
    color: var(--text-muted);
    cursor: pointer;
    padding: 3px 6px;
    border-radius: 3px;
    transition: background var(--transition-speed);
}

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

.find-option input[type="checkbox"] {
    display: none;
}

.find-option:has(input:checked) {
    background: var(--bg-tertiary);
    color: var(--text-accent);
}

.find-count {
    font-size: 12px;
    color: var(--text-muted);
    min-width: 70px;
}

.find-btn {
    padding: 3px 8px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    font-size: 12px;
    cursor: pointer;
    transition: background var(--transition-speed);
}

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

.find-close {
    font-size: 16px;
    font-weight: bold;
    border: none;
    background: transparent;
}

/* ===== Editor Area ===== */
.editor-wrapper {
    flex: 1;
    display: flex;
    overflow: hidden;
    position: relative;
    background: var(--bg-editor);
}

.line-numbers {
    width: 50px;
    padding: 10px 8px 10px 0;
    text-align: right;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.5;
    color: var(--text-muted);
    background: var(--bg-editor);
    border-right: 1px solid var(--border-color);
    overflow: hidden;
    flex-shrink: 0;
    user-select: none;
}

.line-numbers .active-line {
    color: var(--text-primary);
}

.editor-container {
    flex: 1;
    position: relative;
    overflow: hidden;
}

.highlight-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    padding: 10px;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.5;
    white-space: pre-wrap;
    word-wrap: break-word;
    overflow-y: auto;
    pointer-events: none;
    color: transparent;
    z-index: 1;
    tab-size: 4;
}

#editor {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    padding: 10px;
    border: none;
    outline: none;
    resize: none;
    font-family: var(--font-mono);
    font-size: 14px;
    line-height: 1.5;
    color: var(--text-primary);
    background: transparent;
    caret-color: var(--text-primary);
    z-index: 2;
    white-space: pre-wrap;
    word-wrap: break-word;
    overflow-y: auto;
    tab-size: 4;
}

/* ===== Status Bar ===== */
.status-bar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 3px 12px;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    font-size: 12px;
    color: var(--text-muted);
    flex-shrink: 0;
    user-select: none;
}

.status-left, .status-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

.status-sep {
    color: var(--border-color);
}

#language-select {
    padding: 1px 4px;
    border: 1px solid var(--border-color);
    border-radius: 3px;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
    font-family: var(--font-ui);
    font-size: 12px;
    cursor: pointer;
    outline: none;
}

#language-select:focus {
    border-color: var(--border-active);
}

/* ===== Print Styles ===== */
@media print {
    .toolbar, .tab-bar, .status-bar, .find-panel, .line-numbers {
        display: none !important;
    }
    .editor-wrapper {
        overflow: visible !important;
    }
    #editor {
        position: static !important;
        overflow: visible !important;
        height: auto !important;
        white-space: pre-wrap !important;
        color: #000 !important;
        background: #fff !important;
    }
    .highlight-overlay {
        display: none !important;
    }
}

/* ===== Responsive ===== */
@media (max-width: 640px) {
    .toolbar button span {
        display: none;
    }
    .toolbar button {
        padding: 6px;
    }
    .toolbar-separator {
        margin: 0 3px;
    }
    .tab {
        min-width: 60px;
        max-width: 120px;
        padding: 6px 8px;
    }
    .line-numbers {
        width: 36px;
        font-size: 12px;
    }
    #editor, .highlight-overlay {
        font-size: 13px;
    }
}