diff --git a/src/backend/modern.lisp b/src/backend/modern.lisp
index b63de17..498b824 100644
--- a/src/backend/modern.lisp
+++ b/src/backend/modern.lisp
@@ -1,22 +1,320 @@
+(in-package :cl-tty.backend)
+
+(defun hex-to-rgb (hex)
+  "Parse a hex color string like \"#FFD700\" into (values r g b).
+  Also handles 3-digit hex like \"#F00\" (expands to \"#FF0000\")."
+  (let ((clean (string-trim '(#\# #\Space) hex)))
+    (if (= (length clean) 3)
+        ;; Expand 3-digit: #F00 -> #FF0000
+        (let* ((r (parse-integer (subseq clean 0 1) :radix 16 :junk-allowed t))
+               (g (parse-integer (subseq clean 1 2) :radix 16 :junk-allowed t))
+               (b (parse-integer (subseq clean 2 3) :radix 16 :junk-allowed t)))
+          (values (+ r (* r 16)) (+ g (* g 16)) (+ b (* b 16))))
+        (values (parse-integer (subseq clean 0 2) :radix 16 :junk-allowed t)
+                (parse-integer (subseq clean 2 4) :radix 16 :junk-allowed t)
+                (parse-integer (subseq clean 4 6) :radix 16 :junk-allowed t)))))
+
+(defparameter *named-colors*
+  '((:black . 0) (:red . 1) (:green . 2) (:yellow . 3)
+    (:blue . 4) (:magenta . 5) (:cyan . 6) (:white . 7)))
+
+(defvar *theme-colors* (make-hash-table :test 'eq)
+  "Hash table mapping theme keywords to hex color strings.
+Populated by the theme system's load-preset.  Checked by sgr-fg/sgr-bg
+as a fallback when a keyword is not in *named-colors*.")
+
+(defun sgr-fg (color)
+  "Return SGR foreground escape for COLOR."
+  (if (null color) ""
+      (cond ((and (stringp color) (char= (char color 0) #\#))
+             (multiple-value-bind (r g b) (hex-to-rgb color)
+               (format nil "~C[38;2;~d;~d;~dm" #\Esc r g b)))
+            ((keywordp color)
+             (let ((index (cdr (assoc color *named-colors*))))
+               (if index
+                   (format nil "~C[~dm" #\Esc (+ 30 index))
+                   (let ((hex (gethash color *theme-colors*)))
+                     (if hex
+                         (multiple-value-bind (r g b) (hex-to-rgb hex)
+                           (format nil "~C[38;2;~d;~d;~dm" #\Esc r g b))
+                         "")))))
+            (t ""))))
+
+(defun sgr-bg (color)
+  "Return SGR background escape for COLOR."
+  (if (null color) ""
+      (cond ((and (stringp color) (char= (char color 0) #\#))
+             (multiple-value-bind (r g b) (hex-to-rgb color)
+               (format nil "~C[48;2;~d;~d;~dm" #\Esc r g b)))
+            ((keywordp color)
+             (let ((index (cdr (assoc color *named-colors*))))
+               (if index
+                   (format nil "~C[~dm" #\Esc (+ 40 index))
+                   (let ((hex (gethash color *theme-colors*)))
+                     (if hex
+                         (multiple-value-bind (r g b) (hex-to-rgb hex)
+                           (format nil "~C[48;2;~d;~d;~dm" #\Esc r g b))
+                         "")))))
+            (t ""))))
+
+(defparameter *sgr-attr-codes*
+  '((:bold . 1) (:dim . 2) (:italic . 3) (:underline . 4)
+    (:blink . 5) (:reverse . 7) (:reset . 0)))
+
+(defun sgr-attr (attr)
+  "Return SGR attribute escape for ATTR keyword."
+  (let ((code (cdr (assoc attr *sgr-attr-codes*))))
+    (if code
+        (format nil "~C[~dm" #\Esc code)
+        "")))
+
+(defun cursor-move-escape (x y)
+  "Return CSI escape to move cursor to (x, y), 1-indexed."
+  (format nil "~C[~d;~dH" #\Esc (1+ y) (1+ x)))
+
+(defun cursor-style-escape (shape blink)
+  "Return DECSTR escape for cursor shape."
+  (let* ((base (case shape
+                 (:block 2) (:underline 4) (:bar 6)
+                 (t 2)))
+         (code (if blink (1+ base) base)))
+    (format nil "~C[~d q" #\Esc code)))
+
+(defun decicm-begin ()
+  "Return escape to enable synchronized updates."
+  (format nil "~C[?2026h" #\Esc))
+
+(defun decicm-end ()
+  "Return escape to disable synchronized updates."
+  (format nil "~C[?2026l" #\Esc))
+
+(defun osc8-link (url text)
+  "Wrap TEXT in an OSC 8 hyperlink to URL."
+  (format nil "~C]8;;~A~C\\~A~C]8;;~C\\"
+          #\Esc url #\Esc text #\Esc #\Esc))
+
+(defparameter *border-chars*
+  '(((:single :top-left) . "┌") ((:single :top-right) . "┐")
+    ((:single :bottom-left) . "└") ((:single :bottom-right) . "┘")
+    ((:single :horizontal) . "─") ((:single :vertical) . "│")
+    ((:double :top-left) . "╔") ((:double :top-right) . "╗")
+    ((:double :bottom-left) . "╚") ((:double :bottom-right) . "╝")
+    ((:double :horizontal) . "═") ((:double :vertical) . "║")
+    ((:rounded :top-left) . "╭") ((:rounded :top-right) . "╮")
+    ((:rounded :bottom-left) . "╰") ((:rounded :bottom-right) . "╯")
+    ((:rounded :horizontal) . "─") ((:rounded :vertical) . "│")))
+
+(defun border-char (style pos)
+  "Return the Unicode box-drawing character for STYLE at POS."
+  (let ((char (cdr (assoc (list style pos) *border-chars* :test #'equal))))
+    (or char (if (member pos '(:horizontal :vertical))
+                 (case pos (:horizontal "─") (:vertical "│"))
+                 "+"))))
+
+(defclass modern-backend (backend)
+  ((output-stream :initform *standard-output*
+                  :initarg :output-stream
+                  :accessor backend-output-stream)
+   (in-sync-p :initform nil :accessor in-sync-p)))
+
+(defun make-modern-backend (&key color-palette output-stream)
+  (declare (ignore color-palette))
+  (make-instance 'modern-backend :output-stream (or output-stream *standard-output*)))
+
+(defmethod initialize-backend ((b modern-backend))
+  (backend-write b (format nil "~C[?1049h" #\Esc))  ; alt screen
+  (backend-write b (format nil "~C[?1000h" #\Esc))  ; mouse basic
+  (backend-write b (format nil "~C[?1002h" #\Esc))  ; mouse drag
+  (backend-write b (format nil "~C[?1006h" #\Esc))  ; SGR mouse
+  (backend-write b (format nil "~C[?2004h" #\Esc))  ; bracketed paste
+  (backend-write b (format nil "~C[?u" #\Esc))      ; kitty keyboard
+  (cursor-hide b)
+  (finish-output (backend-output-stream b))
+  b)
+
+(defmethod shutdown-backend ((b modern-backend))
+  (cursor-show b)
+  (backend-write b (format nil "~C[?u" #\Esc))
+  (backend-write b (format nil "~C[?2004l" #\Esc))
+  (backend-write b (format nil "~C[?1006l" #\Esc))
+  (backend-write b (format nil "~C[?1002l" #\Esc))
+  (backend-write b (format nil "~C[?1000l" #\Esc))
+  (backend-write b (format nil "~C[?1049l" #\Esc))  ; normal screen
+  (finish-output (backend-output-stream b))
+  (values))
+
+(defmethod suspend-backend ((b modern-backend))
+  (cursor-show b)
+  (backend-write b (format nil "~C[?1049l" #\Esc))  ; normal screen
+  (cursor-move b 0 0)
+  (finish-output (backend-output-stream b))
+  (values))
+
+(defmethod resume-backend ((b modern-backend))
+  (backend-write b (format nil "~C[?1049h" #\Esc))  ; alt screen
+  (backend-write b (format nil "~C[?1000h" #\Esc))  ; mouse basic
+  (backend-write b (format nil "~C[?1002h" #\Esc))  ; mouse drag
+  (backend-write b (format nil "~C[?1006h" #\Esc))  ; SGR mouse
+  (backend-write b (format nil "~C[?2004h" #\Esc))  ; bracketed paste
+  (backend-write b (format nil "~C[?u" #\Esc))      ; kitty keyboard
+  (cursor-hide b)
+  (finish-output (backend-output-stream b))
+  (values))
+
 (defmethod backend-size ((b modern-backend))
-  (flet ((try-ioctl (fd)
-           (let* ((winsize (sb-alien:make-alien sb-alien:unsigned-short 4)))
-             (unwind-protect
-                  (progn
-                    (sb-unix:unix-ioctl fd 21523 (sb-alien:alien-sap winsize))
-                    (let ((cols (sb-alien:deref winsize 1))
-                          (rows (sb-alien:deref winsize 0)))
-                      (when (and (integerp cols) (integerp rows)
-                                 (> cols 0) (> rows 0))
-                        (values cols rows))))
-               (sb-alien:free-alien winsize)))))
-    (or (try-ioctl 0)
-        (try-ioctl 1)
-        (ignore-errors
-          (let* ((cstr (sb-ext:posix-getenv "COLUMNS"))
-                 (rstr (sb-ext:posix-getenv "LINES"))
-                 (cols (when cstr (parse-integer cstr :junk-allowed t)))
-                 (rows (when rstr (parse-integer rstr :junk-allowed t))))
-            (when (and cols rows (> cols 0) (> rows 0))
-              (values cols rows))))
-        (values 80 24))))
\ No newline at end of file
+  (or (ignore-errors
+        (let* ((+tiocgwinsz+ 21523)  ; 0x5413 on Linux
+               (winsize (sb-alien:make-alien sb-alien:unsigned-short 4)))
+          (unwind-protect
+               (progn
+                 (sb-unix:unix-ioctl (sb-sys:fd-stream-fd (backend-output-stream b))
+                                     +tiocgwinsz+
+                                     (sb-alien:alien-sap winsize))
+                 (values (sb-alien:deref winsize 1)  ;; cols
+                         (sb-alien:deref winsize 0))) ;; rows
+            (sb-alien:free-alien winsize))))
+      ;; $COLUMNS/$LINES fallback — some systems return 80x24 from
+      ;; ioctl on stdout's fd even when the terminal is larger.
+      (ignore-errors
+        (let* ((cstr (sb-ext:posix-getenv "COLUMNS"))
+               (rstr (sb-ext:posix-getenv "LINES"))
+               (cols (when cstr (parse-integer cstr :junk-allowed t)))
+               (rows (when rstr (parse-integer rstr :junk-allowed t))))
+          (when (and cols rows (> cols 0) (> rows 0))
+            (values cols rows))))
+      (values 80 24)))
+
+(defmethod backend-write ((b modern-backend) string)
+  (let ((stream (backend-output-stream b)))
+    (write-string string stream)
+    (finish-output stream)
+    (length string)))
+
+(defmethod capable-p ((b modern-backend) feature)
+  (member feature '(:truecolor :osc8 :sync :mouse
+                    :bracketed-paste :cursor-style
+                    :kitty-keyboard)))
+
+(defmethod draw-text ((b modern-backend) x y string fg bg
+                      &key bold italic underline reverse dim blink
+                      &allow-other-keys)
+ (let ((parts (list (cursor-move-escape x y)
+                    (sgr-fg fg) (sgr-bg bg)
+                    (when bold (sgr-attr :bold))
+                    (when italic (sgr-attr :italic))
+                    (when underline (sgr-attr :underline))
+                    (when reverse (sgr-attr :reverse))
+                    (when dim (sgr-attr :dim))
+                    (when blink (sgr-attr :blink))
+                    string
+                    (sgr-attr :reset))))
+   (backend-write b (apply #'concatenate 'string parts))))
+
+(defmethod draw-border ((b modern-backend) x y width height
+                        &key style fg bg title title-align)
+  (let* ((s (or style :single))
+         (tl (border-char s :top-left))
+         (tr (border-char s :top-right))
+         (bl (border-char s :bottom-left))
+         (br (border-char s :bottom-right))
+         (h  (border-char s :horizontal))
+         (v  (border-char s :vertical))
+         (fg-esc (sgr-fg fg))
+         (bg-esc (sgr-bg bg))
+         (reset (sgr-attr :reset))
+         (inner-width (- width 2))
+         (hc (char h 0))
+         (top (if (and title (plusp (length title)))
+                  (let* ((align (or title-align :left))
+                         (max-tlen (- inner-width 2))
+                         (tlen (min (length title) max-tlen))
+                         (trunc-title (subseq title 0 tlen)))
+                    (ecase align
+                      (:left
+                       (let ((right-hyphens (- inner-width tlen 2)))
+                         (concatenate 'string
+                           fg-esc bg-esc tl (string #\Space)
+                           trunc-title (string #\Space)
+                           (make-string (max 0 right-hyphens) :initial-element hc)
+                           tr reset (string #\Newline))))
+                      (:center
+                       (let* ((total-pad (- inner-width tlen))
+                              (left-pad (floor total-pad 2))
+                              (right-pad (- total-pad left-pad)))
+                         (concatenate 'string
+                           fg-esc bg-esc tl
+                           (make-string left-pad :initial-element hc)
+                           trunc-title
+                           (make-string right-pad :initial-element hc)
+                           tr reset (string #\Newline))))))
+                  (concatenate 'string
+                    fg-esc bg-esc tl
+                    (make-string inner-width :initial-element hc)
+                    tr reset (string #\Newline))))
+         (mid (concatenate 'string
+                fg-esc bg-esc v
+                (make-string inner-width :initial-element #\Space)
+                v reset (string #\Newline)))
+         (bot (concatenate 'string
+                fg-esc bg-esc bl
+                (make-string inner-width :initial-element hc)
+                br reset)))
+    (backend-write b top)
+    (loop repeat (- height 2) do (backend-write b mid))
+    (backend-write b bot)))
+
+(defmethod draw-rect ((b modern-backend) x y width height &key bg)
+  (let* ((bg-esc (sgr-bg bg))
+         (reset (sgr-attr :reset))
+         (line (concatenate 'string
+                 bg-esc
+                 (make-string width :initial-element #\Space)
+                 reset (string #\Newline))))
+    (loop :for row :from 0 :below height :do
+      (backend-write b (cursor-move-escape x (+ y row)))
+      (backend-write b line))))
+
+(defmethod draw-link ((b modern-backend) x y string url
+                      &key fg bg)
+  (let ((parts (list (cursor-move-escape x y)
+                     (sgr-fg fg) (sgr-bg bg)
+                     (osc8-link url string)
+                     (sgr-attr :reset))))
+    (backend-write b (apply #'concatenate 'string parts))))
+
+(defmethod draw-ellipsis ((b modern-backend) x y width
+                          &key fg bg)
+  (declare (ignore width))
+  (let ((dots "..."))
+    (draw-text b x y dots fg bg)))
+
+(defmethod cursor-move ((b modern-backend) x y)
+  (backend-write b (cursor-move-escape x y)))
+
+(defmethod cursor-hide ((b modern-backend))
+  (backend-write b (format nil "~C[?25l" #\Esc)))
+
+(defmethod cursor-show ((b modern-backend))
+  (backend-write b (format nil "~C[?25h" #\Esc)))
+
+(defmethod cursor-style ((b modern-backend) shape &key blink)
+  (backend-write b (cursor-style-escape shape blink)))
+
+(defmethod enable-mouse ((b modern-backend))
+  (backend-write b (format nil "~C[?1000h" #\Esc))
+  (backend-write b (format nil "~C[?1002h" #\Esc))
+  (backend-write b (format nil "~C[?1006h" #\Esc))
+  (finish-output (backend-output-stream b)))
+
+(defmethod enable-bracketed-paste ((b modern-backend))
+  (backend-write b (format nil "~C[?2004h" #\Esc))
+  (finish-output (backend-output-stream b)))
+
+(defmethod begin-sync ((b modern-backend))
+  (setf (in-sync-p b) t)
+  (backend-write b (decicm-begin)))
+
+(defmethod end-sync ((b modern-backend))
+  (setf (in-sync-p b) nil)
+  (backend-write b (decicm-end))
+  (finish-output (backend-output-stream b)))
diff --git a/src/backend/simple.lisp b/src/backend/simple.lisp
index e1a9205..4a524e1 100644
--- a/src/backend/simple.lisp
+++ b/src/backend/simple.lisp
@@ -1,22 +1,133 @@
+(in-package :cl-tty.backend)
+
+(defclass simple-backend (backend)
+  ((output-stream :initform *standard-output*
+                  :initarg :output-stream
+                  :accessor backend-output-stream)))
+
+(defun make-simple-backend (&key output-stream)
+  (make-instance 'simple-backend
+    :output-stream (or output-stream *standard-output*)))
+
+(defmethod initialize-backend ((b simple-backend))
+  b)
+
+(defmethod shutdown-backend ((b simple-backend))
+  (values))
+
+(defmethod suspend-backend ((b simple-backend))
+  (values))
+
+(defmethod resume-backend ((b simple-backend))
+  (values))
+
 (defmethod backend-size ((b simple-backend))
-  (flet ((try-ioctl (fd)
-           (let* ((winsize (sb-alien:make-alien sb-alien:unsigned-short 4)))
-             (unwind-protect
-                  (progn
-                    (sb-unix:unix-ioctl fd 21523 (sb-alien:alien-sap winsize))
-                    (let ((cols (sb-alien:deref winsize 1))
-                          (rows (sb-alien:deref winsize 0)))
-                      (when (and (integerp cols) (integerp rows)
-                                 (> cols 0) (> rows 0))
-                        (values cols rows))))
-               (sb-alien:free-alien winsize)))))
-    (or (try-ioctl 0)
-        (try-ioctl 1)
-        (ignore-errors
-          (let* ((cstr (sb-ext:posix-getenv "COLUMNS"))
-                 (rstr (sb-ext:posix-getenv "LINES"))
-                 (cols (when cstr (parse-integer cstr :junk-allowed t)))
-                 (rows (when rstr (parse-integer rstr :junk-allowed t))))
-            (when (and cols rows (> cols 0) (> rows 0))
-              (values cols rows))))
-        (values 80 24))))
\ No newline at end of file
+  (or (ignore-errors
+        (let* ((+tiocgwinsz+ 21523)
+               (winsize (sb-alien:make-alien sb-alien:unsigned-short 4)))
+          (unwind-protect
+               (progn
+                 (sb-unix:unix-ioctl (sb-sys:fd-stream-fd
+                                      (backend-output-stream b))
+                                     +tiocgwinsz+
+                                     (sb-alien:alien-sap winsize))
+                 (values (sb-alien:deref winsize 1)
+                         (sb-alien:deref winsize 0)))
+            (sb-alien:free-alien winsize))))
+      (ignore-errors
+        (let* ((cstr (sb-ext:posix-getenv "COLUMNS"))
+               (rstr (sb-ext:posix-getenv "LINES"))
+               (cols (when cstr (parse-integer cstr :junk-allowed t)))
+               (rows (when rstr (parse-integer rstr :junk-allowed t))))
+          (when (and cols rows (> cols 0) (> rows 0))
+            (values cols rows))))
+      (values 80 24)))
+
+(defmethod backend-write ((b simple-backend) string)
+  (let ((stream (backend-output-stream b)))
+    (write-string string stream)
+    (finish-output stream)
+    (length string)))
+
+(defmethod draw-text ((b simple-backend) x y string fg bg
+                      &key bold italic underline reverse dim blink
+                      &allow-other-keys)
+ (declare (ignore x y fg bg bold italic underline reverse dim blink))
+ (backend-write b string))
+
+(defun %simple-border-char (pos)
+  "Return ASCII border character at POS.
+POS is :top-left, :top-right, :bottom-left, :bottom-right,
+:horizontal, or :vertical."
+  (case pos
+    ((:top-left :top-right :bottom-left :bottom-right) #\+)
+    (:horizontal #\-)
+    (:vertical #\|)))
+
+(defmethod draw-border ((b simple-backend) x y width height
+                        &key style fg bg title title-align)
+  (declare (ignore style fg bg))
+  (let ((h (%simple-border-char :horizontal))
+        (v (%simple-border-char :vertical))
+        (tl (%simple-border-char :top-left))
+        (tr (%simple-border-char :top-right))
+        (bl (%simple-border-char :bottom-left))
+        (br (%simple-border-char :bottom-right)))
+    ;; Position cursor with newlines and spaces (no escape sequences)
+    (dotimes (row y) (backend-write b (string #\Newline)))
+    ;; Top edge with optional title
+    (backend-write b (make-string x :initial-element #\space))
+    (backend-write b (string tl))
+    (if (and title (plusp (length title)))
+        (let* ((align (or title-align :left))
+               (inner-width (- width 2))
+               (max-tlen (- inner-width 2))
+               (tlen (min (length title) max-tlen))
+               (trunc-title (subseq title 0 tlen)))
+          (ecase align
+            (:left
+             (backend-write b (string #\Space))
+             (backend-write b trunc-title)
+             (backend-write b (string #\Space))
+             (backend-write b (make-string (- inner-width tlen 2) :initial-element h)))
+            (:center
+             (let* ((total-pad (- inner-width tlen))
+                    (left-pad (floor total-pad 2))
+                    (right-pad (- total-pad left-pad)))
+               (backend-write b (make-string left-pad :initial-element h))
+               (backend-write b trunc-title)
+               (backend-write b (make-string right-pad :initial-element h))))))
+        (backend-write b (make-string (- width 2) :initial-element h)))
+    (backend-write b (string tr))
+    ;; Sides
+    (loop for i from 1 below (1- height)
+          do (backend-write b (string #\Newline))
+             (backend-write b (make-string x :initial-element #\space))
+             (backend-write b (string v))
+             (backend-write b (make-string (- width 2) :initial-element #\space))
+             (backend-write b (string v)))
+    ;; Bottom edge
+    (backend-write b (string #\Newline))
+    (backend-write b (make-string x :initial-element #\space))
+    (backend-write b (string bl))
+    (backend-write b (make-string (- width 2) :initial-element h))
+    (backend-write b (string br))))
+
+(defmethod draw-rect ((b simple-backend) x y width height
+                      &key bg)
+  (declare (ignore x y width height bg))
+  ;; On simple backend, background fill is a no-op
+  (values))
+
+(defmethod draw-link ((b simple-backend) x y string url
+                      &key fg bg)
+  (declare (ignore url fg bg))
+  (draw-text b x y string nil nil))
+
+(defmethod draw-ellipsis ((b simple-backend) x y width
+                          &key fg bg)
+  (declare (ignore width fg bg))
+  ;; Position using newlines+spaces (simple-backend pattern)
+  (dotimes (row y) (backend-write b (string #\Newline)))
+  (backend-write b (make-string x :initial-element #\Space))
+  (backend-write b "..."))