diff --git a/kernel/fat12.h b/kernel/fat12.h
index 730b144..3da0ae7 100644
--- a/kernel/fat12.h
+++ b/kernel/fat12.h
@@ -2,31 +2,29 @@
 #define FAT12_H
 
 #include <stdint.h>
+#include <stdbool.h>
 
-// --- Configuration ---
 #define FAT12_SECTOR_SIZE 512
 
-// --- On-Disk Structures (Must be Packed) ---
+/* --- On-Disk Structures --- */
 
-// BIOS Parameter Block (Start of Boot Sector)
 typedef struct {
     uint8_t  jump[3];
     char     oem[8];
-    uint16_t bytes_per_sector;    // 512
-    uint8_t  sectors_per_cluster; // 1
-    uint16_t reserved_sectors;    // 1 (Boot sector)
-    uint8_t  fat_count;           // 2
-    uint16_t dir_entries_count;   // 224
-    uint16_t total_sectors;       // 2880
-    uint8_t  media_descriptor;    // 0xF0
-    uint16_t sectors_per_fat;     // 9
-    uint16_t sectors_per_track;   // 18
-    uint16_t heads;               // 2
+    uint16_t bytes_per_sector;
+    uint8_t  sectors_per_cluster;
+    uint16_t reserved_sectors;
+    uint8_t  fat_count;
+    uint16_t dir_entries_count;
+    uint16_t total_sectors;
+    uint8_t  media_descriptor;
+    uint16_t sectors_per_fat;
+    uint16_t sectors_per_track;
+    uint16_t heads;
     uint32_t hidden_sectors;
     uint32_t total_sectors_large;
 } __attribute__((packed)) fat12_bpb_t;
 
-// Directory Entry (32 bytes)
 typedef struct {
     char     filename[8];
     char     ext[3];
@@ -39,29 +37,24 @@ typedef struct {
     uint16_t high_cluster_num; // Always 0 in FAT12
     uint16_t last_mod_time;
     uint16_t last_mod_date;
-    uint16_t low_cluster_num;  // The starting cluster
-    uint32_t file_size;        // Size in bytes
+    uint16_t low_cluster_num;
+    uint32_t file_size;
 } __attribute__((packed)) fat12_entry_t;
 
-// --- Kernel File Handle ---
-// This is what your kernel uses to track an open file
+/* --- Kernel File Handle --- */
+
 typedef struct {
-    char     name[11];
     uint32_t size;
     uint16_t start_cluster;
     uint16_t current_cluster;
-    uint32_t current_sector_in_cluster;
     uint32_t bytes_read;
+    bool     valid;
 } file_t;
 
-// --- Public API ---
+/* --- API --- */
 
-// You must implement this in your disk driver (e.g., floppy.c)
-// Returns 0 on success, non-zero on error.
-extern int disk_read_sector(uint32_t lba, uint8_t *buffer);
-
-void fat12_init();
-file_t fat12_open(const char *filename);
+void     fat12_init(void);
+file_t   fat12_open(const char *filename);
 uint32_t fat12_read(file_t *file, uint8_t *buffer, uint32_t bytes_to_read);
 
-#endif // FAT12_H
+#endif